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Potential Historic Arctic Warming Scenario in the GFS Model Forecast for Late May

For years, Arctic watchers have been concerned that if May and June ran much warmer than average following an equally severe winter, we could see substantial sea ice losses, severe Arctic fires, and related knock-on global weather effects. This May, temperatures over the Arctic Ocean have run much warmer than average. And in the GFS model forecast, we see a prediction for a historic Arctic temperature spike during late May.

(Discussion of a potentially historic Arctic warming event for late May of 2018. Information for this analysis provided by Climate Reanalyzer, Global and Regional Climate Anomalies, and DMI.)

According to GFS model analysis, temperatures for the entire Arctic region could spike to as high as 3.5 degrees Celsius above average from Saturday, May 26 through Tuesday, May 29th. So much warming, if it does occur, would shatter temperature records around the Arctic and accelerate the summer melt season by 2-4 weeks. It would also elevate Arctic fire potentials while likely increasing upstream severe weather risks to include higher potentials for droughts, heatwaves and severe rainfall events (as we have seen recently across the Eastern U.S.).

The model run indicates three ridge zones feeding much warmer than normal air into the Arctic. The zones hover over Eastern Siberia, Western North America, and Central Europe through the North Atlantic and Barents Sea — pushing wave after wave of warmth into the Arctic Ocean region.

(Three ridges transferring heat into the Arctic are feeding the potential for a major polar temperature spike over the next ten days. Image source: Climate Reanalyzer.)

Over the coming days, this three-pronged flood of warm air could push temperatures over the Arctic Ocean to 2-10 C above average temperatures while Western North America, Eastern Siberia, and the Scandinavian countries could see the mercury climb to 5 to 20 degrees Celsius above average. This translates to 70 to 80 degree (Fahrenheit) temperatures for Eastern Siberia above the Arctic Circle, mid 70s to mid 80s for near Arctic Circle Alaska, and temperatures in the 70s to 80s for Scandinavia. For the Arctic Ocean, it means above freezing temperatures for most zones. Zones that are likely to see more rapid sea ice melt as a result.

Upstream effects include the potential continuation and emergence of fixed severe weather patterns. Extreme heat will tend to intensify for Western North America, while a pattern that favors severe rainfall is likely to remain in place for the Eastern U.S. Meanwhile, South-Central Asia through the Middle East are likely to see very extreme daytime high temperatures. Fire risks will tend to rise from Alberta to the Northwest Territory into Alaska and on through Central and Western Siberia as much warmer than normal temperatures take hold and Arctic lightning storms proliferate.

(Forecast Northern Hemisphere temperature anomaly patterns hint at a hot or unstable late spring pattern for many regions as the pole inters record warm territory. Image source: Climate Reanalyzer.)

It’s worth noting that should such an event occur during late May, it would represent yet another major and historic temperature departure for an Arctic zone that has thus far seen severe winter warming and related loss of sea ice. The concern is that eventually such heating would result in ice free conditions during summer — although when is a subject of some debate.

To this point, it is also worth noting that we should take the present GFS forecast with a bit of a grain of salt. Such amazingly warm temperatures are still 6-10 days away. Forecasts beyond the 3 day are notably fickle. And this particular model has run a bit hot of late. However, it is worth noting that the model has been correct in predicting a much warmer than normal May. And that we have already experienced one historic temperature spike during early May. So a pattern that demonstrates the potential for such extreme warming has clearly taken hold.

 

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Warm Oceans, Displaced Polar Air: Why the Eastern U.S. is Likely to See Very Severe Rainfall During May

During recent years, warm ocean surfaces have loaded up the atmosphere with increasing levels of moisture. This moisture, in turn, has fueled more powerful rain storm events across the globe. Meanwhile, climate change is generating regions of increased instability by placing much warmer than normal air masses in confrontation with cold air displaced from a warming Arctic Ocean region.

(How climate change is impacting severe weather potentials across the U.S. East Coast during May. Data provided by Earth Nullschool, Climate Reanalyzer, and the National Weather Service.)

During the coming days, this kind of pattern will generate the potential for severe rainfall events across the U.S. East Coast. NOAA is predicting that between 3-7 inches of rain is likely to fall over the next 5-7 days. But due to the unusual situation, locally extreme and unexpected events may occur.

This severe weather potential has been fed by a combination of factors. A warmer than normal Arctic Ocean has shoved cold polar air south over the Hudson Bay region. The resulting trough is generating stormy conditions and atmospheric instability over much of Eastern North America. To the south and east, much warmer than normal sea surfaces have loaded up the atmosphere with extremely high moisture levels.

(NOAA shows that heavy rainfall is likely to dominate large portions of the Eastern U.S. over the coming weeks. With a number of climate change related influences at play, the potential for outsized severe weather events exists. Image source: NOAA.)

It’s the kind of pattern — within a highly charged atmosphere — that is capable of producing serious instances of severe weather. Heavy rainfall, hail, lightning and tornadoes are all more likely. Factors associated with climate change contributing to the situation include — much warmer than normal ocean surfaces off the U.S. Eastern Seaboard and Gulf Coast, a much warmer than normal Arctic Ocean region for this time of year, displaced polar air near Hudson Bay, and warmer than normal temperatures over much of the U.S.

As Greenland melt comes more into play, and as temperatures continue to spike higher over the Arctic Ocean in coming years, we can expect to see similar patterns producing greater instability and more intense storms. Particularly for the land zones near the North Atlantic. And so what we are seeing now is a likely prelude of events to come as the Earth continues to warm coordinate with continued fossil fuel burning — with mitigating factors primarily involving reduced carbon emissions.

Arctic Ocean Deep in the Grips of May Temperature Spike; Beastly Summer Melt Season on the Way?

The Arctic Ocean as it appeared from space on May 6, 2018. Image source: NASA Worldview.

The Arctic sea ice is presently at its second lowest extent ever recorded in most of the major monitors. However, May is shaping up to be far, far warmer than normal for the Arctic Ocean region. If such high temperatures over this typically-frozen part of our world continue for much longer than a couple of weeks at this key time of year, precipitous summer melt is sure to follow.

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During recent years there has been much speculation about when the Arctic Ocean will start to experience ice-free summers as fossil fuel related industries pump higher and higher volumes of greenhouse gasses into the atmosphere. In the early-to-mid 2000s, scientific consensus was that melt would tend to be more gradual and ice-free summers would hold off until the final decades of the 21st Century when the world was around 3-4 C warmer than 19th Century averages.

But the Earth System is far more sensitive to temperature increases than the early forecasts expected. Major Arctic sea ice losses surprised the world during September of 2007 and subsequently in the same month of 2012. Now, it is obvious that a pattern of far more rapid sea ice melt has taken hold. And the scientific consensus appears to have settled on a more likely and much nearer date around the early 2030s — when the world will have warmed by about 1.6 degrees Celsius.

(An oddly warm pattern in which above freezing temperatures have come early to the High Arctic is setting up during May of 2018. Content Source: Climate Reanalyzer. Video source: Scribbler’s Youtube.)

However, when it comes to sea ice, nothing is certain at this time. Any single Arctic year in which temperatures spike — particularly during normal melt season — could result in the losses that we once expected to occur much later in time.

There are many factors that will ultimately determine when a summer ice free state occurs. Warm winters are a major one. And the past two years (2017 and 2018) have seen Arctic winters in which temperatures hit some ridiculous high extremes. But another major factor is the set-up to Arctic summer that takes place during the window months of May and June.

Neven, one of our best Arctic sea ice watchers (you can check his blog out here), notes:

May and June are very important for the rest of the melting season. Not only do we now see these warm air intrusions, but high pressure maintains its presence over parts of the Arctic as well (which means relatively cloudless skies -> insolation -> melt onset and melt pond formation -> preconditioning of the ice pack -> melting momentum that gets expressed during July and August, regardless of the weather)… We have to wait and see what happens, step by step, but this isn’t a good start for the ice.

If May and June are unusually warm, particularly over the Arctic Ocean, then the sea ice — which is already greatly weakened — is bound to face an extended period of above-freezing temperatures. If such a period stretches for 5 months from May through September rather than the typical 4 months (June to September), then we are more likely to see the Arctic Ocean briefly flip into an ice-free or near ice-free state for the first time in human history.

(The coming week is expected to feature between 1 and 10 C above average temperatures for locations across the Arctic Ocean. These are very strong warm departures during May. Last week saw similar extreme warm departures. And we are already starting to see sea ice losses pile up. Image source: Global and Regional Climate Anomalies.)

This year, May is shaping up to be much, much warmer than normal for the High Arctic. Already, a large May temperature spike has occurred (see right image below). A temperature spike which is predicted to continue for at least the next ten days.

Not to put too fine a point on it, but this severe warming trend might end up presenting a bit of a problem. The extended period of melt mentioned above may begin in force — setting off a chain of feedbacks that could tip the Arctic Ocean into a far less frozen or even an ice-free state (under absolute worst case scenarios) this year.

To be clear, this is not a forecast that such a condition is bound to occur during 2018. It is just an analysis of underlying trends and a statement that risks are higher if such trends as we now observe continue. Late May could flip to a cooler than normal regime. June could be cooler and cloudier than normal (as happened during 2016 and 2017). And if that happens again, we may be spared.

(Average Arctic temperatures for 2017 [left] and 2018 [right]. The red line depicts the yearly temperature trend. The green line depicts the Arctic climatological average for 1958-2002 [which was already warmer than normal]. Note the big temperature spike in the right hand graph. That’s where we are now. Image source: DMI. For further reference, see Zack Labe‘s composite temperature analysis for the 80 North region.)

However, we are already on a much higher ramp for spring temperatures in the northern polar region than during 2017. And though 2016 saw a slightly warmer than normal spring near the pole, the May 2018 spike already far exceeds anything we saw at that time. So much, in fact, that present temperatures for May 6 are comparable to those typically seen during early June from the 80 degree N Latitude line to the Pole.

This higher ramp and related record warmth is already accelerating melt. Sea ice losses over recent days have greatly picked up and we are getting closer to record low daily ranges. If melt accelerates to a point, the greatly expanded darker ocean surfaces will draw in more heat from the sun’s rays during June — potentially overcoming the impact of the increased early summer cloudiness we have seen during recent years. Such a scenario, if it continues to develop, would be a nightmare from the climate change perspective.

Seven Inches of Snow Dumped on Northeast as Another Major Arctic Warm-Up is Underway

As an April snowstorm strikes the U.S. Northeast, major global weather stories related to climate change are unfolding in real time. For today, we again find that none of the key climate zones feature below average temperatures even as a ten-day-long Arctic warm spell appears to be on tap.

Very Warm Arctic in Early April

(Another big Arctic warm-up drives cold air southward. The result is snow over the U.S. Northeast even as parts of the Arctic Ocean are experiencing an early thaw. Image source: Climate Reanalyzer.)

Warm winds driving northward over eastern Siberia, on the back side of a high pressure ridge, are delivering yet one more big dose of near or above freezing temperatures to this Arctic region. From the Chukchi Sea through the Bering Strait and on into East Siberia, temperatures range from 10 to 22 degrees Celsius above average. The Bering itself has been mostly swept clean of sea ice — with severe record low ice extent readings for this zone during early April.

Throughout winter, the Bering and Chukchi have received wave after wave of much warmer than normal air from the ocean zone to the south. This tendency for warm air propagating northward through the Pacific is one that is often triggered by La Nina — a periodic pattern of Pacific Equatorial surface water cooling that became a dominant feature of 2018 winter weather. However, globally warmer than normal ocean waters and, in particular, much warmer than normal sea surface temperatures in the Northeastern Pacific appear to have greatly enhanced the heat influx.

(Much warmer than normal sea surface temperatures in the Northeastern Pacific this year have provided a pathway for warm air to invade the Arctic. Meanwhile, La Nina and Polar Amplification generate a combined influence that weakens the Jet Stream and facilitates atmospheric ridges in this zone. Image source: Earth Nullschool.)

These warm waters at the middle to northern latitudes have developed a pathway that enhances the northward flow of tropical air masses over the Pacific Ocean. Meanwhile La Nina’s Equatorial cooling combines with climate change’s amplified polar warming to slow down the Jet Stream — further enabling this south-to-north heat transfer. As we have seen time and time again, human-forced global warming generated chiefly by fossil fuel burning is developing an atmospheric and oceanic handshake with past understood synoptic trends to produce an out-sized Arctic warming.

Bering Sea Almost Completely Cleared of Ice

This severe warming is plainly visible as open water is driven by outlandish temperatures well north and through the Bering Strait during early April. A time when ocean ice typically extends more than 150 miles south of Ninivak — bridging the water zone from Bristol Bay to the Kamchatka Peninsula.

(The Bering Sea is typically ice-choked during April. And during a normal year all the water zones in the above image would be covered with ice. But this spring, sea ice extent there is at never-before-seen record low levels. Image source: NASA Worldview.)

The impact is quite dramatic. During February, Bering Sea Ice hit 100,000 square kilometers below previous record lows for the Month. These record low extents continued throughout March and into early April when, today, we find that Bering sea ice extent is between 150,000 to 200,000 square kilometers below the previous record lows for the day and about half a million square kilometers below the seasonal average.

Putting this loss into context, half a million square kilometers is a region that splits the difference in size between the land mass area of California and Texas.

According to GFS model runs, the present Bering-East Siberia warm spell should last for another 2-3 days even as larger Arctic warming in the range of 2.4 to 3.2 degrees Celsius above average for the entire 66 North Latitude zone and on poleward is expected to continue through the ten day horizon. These warmer than normal temperatures should retard typical seasonal sea ice thickening in the far northern regions even as edge ice zones like those in the Bering, Baffin Bay, and the Sea of Okhotsk experience early spring melt and erosion.

New England Spring Snow

As warm air invades the Arctic — a feature that has become more and more prevalent as the globe itself has heated up — it tends to drive cold air southward over the North American, Asian, and European Continents. In this case, the warm air invasion coming from the Siberian side is displacing Arctic air over North America. As a result, and much to the delight of myth-enraptured climate change deniers everywhere, we have been treated to a rare, if not unheard of, spring April snowstorm in New England.

(Increasingly, there have been indications that polar warming related to global warming is influencing storm tracks and ridge and trough patterns in the Northern Hemisphere Jet Stream. The result is a stronger influence on Mid-Latitude Northern Hemisphere weather. Image source: Arctic Change and Possible Influence on Mid-Latitude Climate and Weather.)

According to local weather reports, as much as 7 inches of snow were dumped in intense 2-inch-per-hour bursts over parts of New England last night as a brief but intense storm roared through the region. The cold air, driven south by the recent warm polar air invasion, encountered high atmospheric moisture levels bleeding off a much warmer than normal Gulf Stream lurking just off-shore. The result, as has been the case during recent intense rain and snowstorms, was enhanced convection. This greater atmospheric uplift, in turn, produced an out-sized spring precipitation event. With below freezing temperatures driven far to the south by warm air entering the Arctic, the Northeast saw its first significant April snow event since 1982.

An April 6th to 7th Snowstorm for the U.S. South on the Way?

Further fodder for the climate change denial community supported by the anti-information campaigns of Fox News and others, may emerge by next weekend as another big push of cold air could help to develop a snow and ice storm stretching from Oklahoma through the Carolinas. Cold air driven out of the Arctic and southward over the Eastern and Central U.S. could result in 10 to 18 degree Celsius below average temperatures in that region. Moisture bleeding off the much warmer than normal Gulf of Mexico and Atlantic Ocean could be injected into this cold trough as a related storm develops. The result is a potentially unusual snow and ice storm. And an intense event off this kind, should it develop, would be a very odd weather event during U.S. spring-time.

(Another odd spring U.S. Snowstorm may be on the way for April 6th and 7th according to GFS model forecasts. Image source: Tropical Tidbits.)

Meanwhile, the U.S. tendency in the model forecasts is for warmer than normal temperatures in the West, cooler than normal temperatures in the East through the middle of April. It’s worth noting that the forecast also shows highly variable temperatures with strong swings between warm and cold throughout this period for most U.S. regions. As a result, as the Arctic remains much warmer than normal over the next ten days, the U.S. is likely to experience periods of both extreme warmth and extreme cold relative to climatological averages for this time of year.

Final Points — Intense U.S. Spring Snowfall Events a Likely Upshot of Polar Warming

Putting all these dynamics into context, we can sum up by making the following statements:

  1. April snow and even April blizzards are not unheard of for the U.S. East. That said, the recent events are odd and outside the context of regular U.S. weather patterns — particularly when it comes to precipitation intensity.
  2. Arctic warming and loss of regional sea ice, such as that seen in the Bering, is historically unprecedented during 2018. This is a continuation of an observed trend of polar amplification and severe warming seen during recent years.
  3. No major global climate zones show below normal temperatures on April 2, 2018. That said, a high variance in middle latitude northern hemisphere temperatures presently exists — with regions of intense cool and intense warmth interspersed.
  4. Snowstorms in the U.S. Northeast during April do not disprove global warming or a related shift to increasing climate extremes. In fact, they appear to be an aspect of it.

Unusually Warm Early Arctic Spring Predicted Following Second Lowest Sea Ice Maximum on Record

After a brief Arctic cool-down late during a much warmer than usual freeze season, sea ice extents tortuously rose out of record low daily ranges during mid-March. This feeble climb was enough to barely hit above 2017’s record low maximum extent. It did not, however, push the Arctic out of its present trend of long term declines. Moreover, we are again set on a very low platform for sea ice as we enter what is predicted to be a warmer than normal start to melt season.

(Arctic sea ice losses are a long term trend that has been in place since the early to mid 20th Century. The recent satellite record captures this ongoing loss due to polar warming and triggered primarily by fossil fuel burning. In keeping with this trend, 2018 saw the second lowest sea ice extent maximum on record. Image source: Zack Labe. Data Source: JAXA.)

Arctic sea ice extent measured by JAXA and depicted above by Arctic observer Zack Labe, hit 13.89 million square kilometers on March 17th. Given the fact that warmer Arctic temperatures are now on the way, this is likely the furthest sea ice will extend in the northern polar region during 2018. By comparison, 2017 sea ice extent maxed out at 13.88 million square kilometers on March 6th of that year. As a result, 2017 just barely beat out 2018 as the lowest maximum extent in the satellite record according to JAXA.

A brief spate of cooler than average temperatures contributed to a short period of expanding sea ice late during freeze season. This cool snap in a much warmer than normal winter overall, has now ended. And the forecast shows that warmer to much warmer weather for late March may well be on tap.

Over the next week and a half, Arctic temperatures are expected to range between 0.2 to 0.8 C above average. This may not sound like much compared to the past winter which experienced long periods of 3-5 C above normal temperatures. However, the transition to spring and summer typically shows a regression toward baseline averages. In other words, since winter is where we are seeing most of the climate change related warming at present, even slightly warmer than normal temperatures during spring and summer can have an outsized impact. Especially following a very warm winter like the one we have just seen.

(The ten day forecast is presently predicting a very substantial Arctic warm-up. If this forecast is correct, it could result in a fast start to melt season. With sea ice extents already near record low levels, this potential is rather concerning. Image source: Climate Reanalyzer.)

Keeping this thought in mind, we are more likely to see slowly mounting sea ice losses over the coming days in various regions. Especially on the Pacific side of the Arctic — which is presently seeing above freezing temperatures running up through the Bering and well into the Chukchi seas. Given such a strong warm wind invasion over a key region of ice, we are very unlikely to see sea ice expansion beyond the present maximum.

Looking at the long term forecast, we find that the Arctic is expected to experience substantial warming — especially for spring. And this warming may serve to accelerate melt beyond typical rates for this time of year. The tendency for Pacific emerging warm winds appears to be in place. And by April 1st, a large plume of abnormal warmth is expected to run up from the Pacific and Eastern Siberian side of the Arctic. This plume is forecast to spread deep into the High Arctic — driving overall temperatures for the zone to 4.1 C above average with local temperatures between 20 and 25 C above average. If the present forecast holds, this unseasonal flow will also result in large regions of the East Siberian Sea experiencing above freezing temperatures for brief periods.

Taken in the greater context, if the predicted warm pattern of the next ten days becomes more of a trend for spring of 2018, then the near record low maximum of 2018 could well be followed by significant losses during melt season. Definitely a trend to keep an eye on.

Polar Warming Spawns More Severe Winter Storms

So there’s a lot of groundbreaking work going on in the climate sciences right now. And a major focus is evidence that winter polar warming events are increasingly connected to blizzards and storms in places like Europe and North America. Storms that are both historically powerful and that occur with greater frequency.

(A historic nor’easter produces major flooding on the U.S. East Coast even as a blizzard pounds the UK in early March. Were these extreme storms linked to human-caused climate change and related rapid polar warming? A new scientific study says — yes. Image source: NASA Worldview.)

A new study led by pioneers in the emerging field of climate change attribution for extreme weather events (including the notable Dr. Jennifer Francis), finds:

Recent boreal winters have exhibited a large-scale seesaw temperature pattern characterized by an unusually warm Arctic and cold continents… Using a recently developed index of severe winter weather, we show that the occurrence of severe winter weather in the United States is significantly related to anomalies in pan-Arctic geopotential heights and temperatures.

In particular, the authors discovered thatwinter storms were two to four times more likely when the Arctic is abnormally warm, compared to when it was abnormally cold (emphasis added).”

Stronger, More Frequent Storms

This is a rather big deal for a number of reasons. First, it’s an observational confirmation of earlier scientific work predicting just these kinds of extreme weather instances due to polar warming and related climate change. Second, it’s another indicator that human-caused climate change is pushing us into a period of much stormier weather for the North Atlantic region during fall and winter.

(A new study in the journal Nature finds that winter storms in the U.S. are two to four times more likely when the Arctic is abnormally warm than when it is abnormally cold. Due to human-caused climate change, the Arctic is now warming up at a rate two times faster than the rest of the globe (emphasis added). Image source: Atmospheric and Environmental Research.)

With the new NASA global temperature data set out, I thought we’d take this opportunity to apply a bit of context to apparent stormy changes we see at present in winter weather patterns.

The first bit that I’d like to be crystal clear about is that the Arctic, overall, has become much, much warmer than usual during winter. That this warming spike occurs in the context overall global warming. And that this polar warming is increasingly associated with severe weather events in the middle latitudes and especially over the land and North Atlantic mid latitude zones.

The above graph shows polar temperature anomalies from the surface (1000 mb/2 meter) of the Earth to the top regions of the atmosphere (10 mb/25 kilometers). Along the bottom of the graph, we have a list of extreme weather events. Analyzing the graph we find that major polar warming associated with extreme temperature increases at the bottom of the atmosphere all the way through to the stratosphere correlate with recently more frequent historic blizzards and nor’easters in the regions mentioned.

Polar Warming Flushing Cooler Air into the Middle Latitudes

In previous posts, I used the ground-breaking scientific research of Dr. Jennifer Francis and others as a basis to analyze how energy transfer into the polar zone in the form of heat build-up has generated these extraordinary temperature extremes. How this ramping heat is associated with polar amplification — an aspect of human-caused climate change. And how these warming events can have upstream (Jet Stream) impacts that increase storminess in the middle latitudes.

(From January [top] to February [bottom] the pole heats up and extreme weather events ensue. Image source: NASA.)

But let’s take this analysis a step further to look at, as January progressed into February, where it got warmer, where it got colder, and where the big storms fired off.

The maps above show global temperature anomalies (NASA) for January (top) and February (bottom). And looking at those maps we find that the polar region heated up significantly from already warm ranges of 4 to 6.9 degrees Celsius above average during January to an amazing 4 to 12.3 C above average during February.

As this relative polar warming increased during February, the NASA maps show that colder than normal temperatures expanded over North America through Canada and parts of the Northern U.S. even as a cold spell began to blossom in Europe. Cold pools that were fed by Arctic air shunting southward as the Polar Vortex collapsed and remnant continental troughs emerged.

NASA’s zonal anomaly measures provide further evidence for this trend.

(Major northern polar warming from January [top] to February [bottom] is clearly visible in NASA’s zonal anomalies maps. Note that despite cold air excursions into North America and Europe, most zonal regions are warmer to much warmer than average.)

For here we find that as temperatures spiked from 4.5 degrees Celsius above average in the polar region of 80 to 90 degrees north latitude during January to an amazing 11 degrees above average during February, the region of 45 to 70 N dipped from 1 to 3 C warmer than average to 0.8 to 2.5 C warmer than average.

Note that the zonal middle latitude continental cooling is moderated by both the relatively warmer oceans and by very strong ridge zones running through these regions. But that the trough regions over both Europe and North America produced locally frigid temperatures and related instances of extreme weather.

Putting all these maps together from top to bottom we find that the polar warming events coincided both with mid latitude cooling even as we saw extreme snowfall in Canada and Montana, historic cold and snowfall in Europe and the UK, record flooding in the Central U.S., and record heat along the U.S. East Coast. We also find that the developing deep trough over Canada due to the expulsion of polar air southward in turn produced the succession of instabilities that would later spawn 3 very severe nor’easters off the U.S. East Coast during March.

Of course, all of these severe weather events are happening in the context of months that are around 1 degree Celsius warmer than 1880s averages globally. That January was the fifth hottest on record and that February was the sixth hottest on record during a La Nina that, all things being equal, should cause the world to be cooler than average.

But as we can see clearly here, all things are not equal — human-caused climate change is a big spoiler.

Sudden Stratospheric Warming and Polar Amplification: How Climate Change Interacts With the Polar Vortex

Over the past few years, the term Polar Vortex has dominated the broadcast weather media — gaining recent notoriety due to increasingly extreme weather events associated with a number of disruptions to Arctic atmospheric circulation patterns. In short, this swirl of cold air over the furthest north regions is being intensely disrupted by warm air invasions — both at the surface and in the upper levels of the atmosphere. A subject that we’ll explore further as part of this analysis.

Take the recent extreme February warming at the North Pole in which temperatures there rose to above freezing even as a major cold snap slammed into Europe this week. We’ve seen such varied headlines as Yes the North Pole is Warmer than Europe Right Now and Arctic Warm Event Stuns Scientists.

When it’s warmer at the pole than in Europe, it’s a sign that the weather is clearly out of whack. Especially when temperatures in a region spanning tens of thousands of square miles over the Arctic rocket to between 40 and 63 degrees Fahrenheit above normal. Scientists are notably concerned. Dr. Michael Mann, one of the world’s foremost experts on climate change characterized the polar warming event as:

…an anomaly among anomalies. It is far enough outside the historical range that it is worrying — it is a suggestion that there are further surprises in store as we continue to poke the angry beast that is our climate.

But what’s driving all this? Dr. Mann gives us a bit of a hint by describing our climate as an angry beast that’s being poked.

(Polar Amplification writ large. The entire region of the Arctic above the 80 degree North Latitude line has been 8.64 degrees Celsius warmer than normal for all of 2018 thus far. This is an extraordinary departure for a region that plays a critical role in how the Earth’s climate system functions. Image source: DMI.)

Perhaps another way to say it is that it’s a warming atmosphere that’s prodding the Jet Stream to take a chunk out of the Polar Vortex.

How might this work?

First, surface warming in the Arctic caused by increased radiative forcing from rising greenhouse gas levels and by follow-on reductions of Arctic sea ice and snow result in less temperature difference between the Pole and the Equator. This surface warming translates into higher levels of the atmosphere through convection.

Temperature difference is what drives the upper level winds. So a lower difference in temperature causes these winds to slow. When the Jet Stream winds slow, they tend to meander — forming large ridges and deep troughs. The elongated ridges and troughs eventually break like waves — pushing against the circulation of the Polar Vortex.

(NOAA graphic shows how a weak jet stream results in changes in atmospheric circulation and increased disruption of the Polar Vortex.)

When this happens, the speed of the winds that make up the Polar Vortex slow down and sometimes reverse. This results in the collapse of the column of upper level air held aloft by the Vortex’s winds. When the air collapses, it compresses, causing the stratosphere to warm. This falling column of warm air then can end up acting like an atmospheric wedge — driving the Polar Vortex apart and causing it to split.

The split then tends to generate smaller funnels that capture polar air and pull it south. Beneath the funnels, it can be quite cold as Arctic air invades places like North America or the UK (as happened this week). But at the Pole, where the cold air should typically reside, it warms up enormously.

That’s how, under a regime of human-forced climate change, you can end up with periods where temperatures are warmer at the Pole than they are in Europe.

It’s worth noting that Polar Vortex collapse events did occur in the past. But not in such a way that generated the kinds of historically extreme Arctic temperatures we see today. The primary driver for the recently increased extremity of weather driven by Polar Vortex collapse events being human-caused climate change, Polar Amplification, and related influences on the Jet Stream.

Warmed, Wet and Blocked: Another Storm Taking Aim at the Flooded Central U.S. is Expected to Transition into a Stalled Nor’Easter

The Ohio River Valley is now reeling from the worst flooding event of the past 20 years. Yet one more major event fueled by disruptions to the Earth’s atmosphere facilitated by human-caused climate change. But with another serious plume of moisture issuing from the warmer than normal waters of the Gulf of Mexico, more heavy rains are heading toward a storm-battered Central U.S.

(One more big moisture plume arises from a warmer than normal Gulf of Mexico. It will help to fuel a major storm system that is expected to impact a large swath of the U.S. for most of this week. Image source: Earth Nullschool.)

The set-up is similar to previous events of the past two weeks. A strong high pressure system over the Northeast is pulling a heavy load of moisture from a much warmer than normal Gulf of Mexico. Sea surface temperatures there, according to Earth Nullschool reanalysis, range from less than 1 C warmer than normal in the southern Gulf to as much as 5 C warmer than normal in the northern Gulf. Last week, these warmer than normal sea surfaces helped to fuel record atmospheric moisture levels along with historically heavy rains.

This week’s atmospheric moisture pulse will be picked up by a trough sweeping into the Central U.S. over the next couple of days. There, it will help to pump up a series of heavy storms that are predicted to dump another 3-7 inches of rain over the Mississippi River Valley this week. Note that this is on top of the 5-15 inches of rain that has already been dumped over the region during the last two weeks.

(NOAA composite radar imagery shows observed precipitation totals for the U.S. during the past 14 days. Note that another batch of heavy rains is headed directly for the region that has already been hit the hardest.)

Persistent extreme weather patterns of this kind are an aspect of human-forced climate change in that polar warming can result in Jet Stream blocking patterns that cause weather systems to stick around or repeat for long periods of time. This is particularly the case with the storm system now developing in the Central U.S. For as the storm strengthens and moves slowly eastward, it is expected to deepen into a powerful coastal low. This low is predicted to then rake the Northeast U.S. coast with 60 mph winds, heavy rain, high surf and coastal flooding.

As the storm’s eastward passage is blocked by the same weather system that so recently warmed the far north to such extreme winter temperatures, it is expected to linger off the U.S. East Coast even as it intensifies. Due to this predicted stall, the Northeast U.S. is facing the potential of multiple storm tides in which wind-driven water piles up — exacerbating coastal flooding.

(Very strong northeasterly winds are expected to rake the coasts of Maine and Massachusetts by March 2 according to GFS model forecasts. Image source: Earth Nullschool.)

Though the shape of the present storm is still a bit unclear, it is likely to both further exacerbate already severe flooding over the Central U.S. even as it generates some serious coastal flooding potentials for the Northeast by the end of this week. What is also clear is that a warming polar environment is contributing to these upstream severe weather events by increasing their persistence even as warming ocean surfaces are helping to feed them with larger moisture loads which generates higher potential storm and rainfall intensity.

A Large Area of Open Water Forms in the Melting Sea Ice North of Greenland During February

In concert with an unprecedented polar warming event, it now appears that the Atlantic side of the Arctic Ocean is seeing some severe sea ice losses.

Warm winds blowing at up to gale force intensity from the south have assaulted the ice with high waves and above-freezing temperatures for about four days now. The ice edge north of Svalbard is being rapidly beaten back. Perhaps more disturbing, is the fact that the ice pack to the north of Greenland has also now withdrawn — opening up a huge polynya.

(Massive hole in the sea ice expands north of Greenland on February 26th. Image source: NASA.)

Looking at the N. Greenland area, we find a fractured, thinning mess along a region of sea ice that should be meters thick and growing thicker at this time in February. Such a state would be remarkable during summer time, but is much more-so in what should be the dark chill of winter polar night.

To be clear, as Neven notes in his most recent Sea Ice Blog, it’s not simply wind blowing the ice around here. It’s melt due to temperatures rising between 40 and 60 F above average over a large region of the Arctic. A region that yesterday saw a 33-34 F (1-2 F above freezing) temperature at the North Pole.

Closer to the massive expanse of water opening up in the ice, Cape Morris Jesup, the furthest north point in Greenland, has now experienced 61 melting hours during winter in 2018. This is comparable to 2011, which set the previous record for winter and early spring melt at 16 hours for the Morris Jesup location. This weekend, the typically frigid point on Greenland’s north coast saw a 43 degree Fahrenheit high in the 24-hour-long darkness (no sunlight or insolation) and at a time when usual daily peak readings hit a frosty -20 F.

The underside of sea ice melts at around -2 C, due to the salt content in the water. But surface portions of the ice still need above freezing temps to result in melt and ponding. Since this region of the Arctic tends to remain near or well below freezing year-round, the present temperatures are enabling unprecedented winter damage to the ice and the environments it supports.

Overall, Arctic sea ice extent is now at record low levels for this time of year. According to JAXA, hitting 13.64 million square kilometers today — or nearly 2 million square kilometers below 1980s averages.

These record daily and seasonal lows are occurring following a major loss of ice in the Bering Sea and in concert with the rapid sea ice setbacks we are presently seeing on the Atlantic side.

It is possible, given the present trend, that the Arctic will experience back-to-back years of record low seasonal ice during winter. 2016-2017 saw a crash in winter sea ice and we are presently even below the record low extents seen at that time.

(Arctic Basin sea ice is at record lows and trending lower. Image source: The Arctic Sea Ice Blog. Graph by Wipneus.)

Only a month and a half of typical freeze season remains. But ten day forecasts indicate that Arctic region mean temperatures might return closer to normal ranges (0 to 1 C above average as opposed the 3-6 C above average) and could allow for some moderate recovery of the substantially reduced winter ice pack.

Overall, though, the tale so far has been one of highly unusual melt and warming. One that highlights the serious and worsening impacts of human-caused warming and related polar amplification.

(UPDATES TO FOLLOW)

A Hole in Winter’s Heart: Temperatures Rise to Above Freezing at the North Pole in February

“Weather is not Climate.”

But when a warm air influx carves a wide-ranging above-freezing hole into the heart of what should typically be ice-solid Arctic winter, then maybe it’s time to start re-evaluating the gist of the statement.

(Today, on Sunday February 25, 2018 at 0900 UTC — temperatures rose to above freezing at the North Pole. This event, which is probably unprecedented or, at the very least, an extreme instance in the polar record, is an exemplar — or a good example — of the kinds of wrenching weather changes we can expect as a result of human-caused climate change. Image source: Earth Nullschool. Data source: Global Forecast System Model.)

Weather and climate are inexorably married one to the other. Though weather is often variable and tied to locality, climate is broader-ranging and roughly characterized as average weather over 30 years. When climate changes, it ultimately changes average weather. It thus changes the rules in which weather occurs. So you can end up with weather events that are typically not common or have never been seen before — like category six hurricanes, much more heavy rainfall events, historic and unprecedented droughts, and above freezing temperatures at the North Pole during February even as Arctic air is driven south over Europe.

In the context of climate change, what we’re talking about is average global weather across the span of multiple decades. In some locations, this ongoing climate change has resulted in very little perceptible weather change. In other locations, and this is more and more-so the case, the changes to weather are both disruptive and profound.

We could say that they are, as Dr. Sarah Myhre noted in our little climate and weather chat yesterday, exemplars — or good examples of alterations that are characteristic of human-caused climate change.

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Since late January, we’ve been tracking the potential for just such an exemplar extreme weather event — temperatures rising to above freezing at the North Pole during February.

The persistent weather patterns necessary for such an event were already well in play. At the surface, warm air was continuously running northward just east of Greenland — born pole-ward by powerful storms and frontal systems. At the upper levels of the atmosphere, a huge plug of warm air was developing. One that invaded the stratospheric levels of the atmosphere by the week of February 4-11. This plug, in synergy with surface warming, tore apart the heart of cold at the roof of our world that we call the Polar Vortex.

 

(Daily mean temperatures for the entire region of the Arctic above the 80 degree north latitude line rocketed upward to new records over recent weeks. Most recent temperatures are comparable to those typically seen during late May. Image source: Zachary Labe, Arctic Temperatures.)

Nodes of cold air from the remnant Polar Vortex spiraled south — bearing with them regional packets of Arctic air and setting off extreme cold weather in the middle latitudes. Meanwhile, the polar zone just kept warming up into ranges that were increasingly uncharacteristic of Arctic winter.

An extreme wave in the Jet Stream was developing and elongating over the North Atlantic, delivering more and more warm air northward.

By February 21st, the wave had extended into a knife-like extension east of Greenland and through the Barents Sea. Beneath this abnormal Jet Stream wave, which was starting to look more and more like a trans-polar river (of a kind predicted by Dr. Jennifer Francis as a result of human-caused Polar Amplification), was an intensifying thrust of outlandishly warm surface air.

(Jet stream wave originating near Spain extends northward past the North Pole on Sunday, January 25, 2018. Image source: Earth Nullschool.)

Over the past 72 hours, gale force warm, southerly winds gathered in the Atlantic, then blasted north.

At this point, we were starting to see some seriously outlandish temperatures in the higher latitude regions. Cape Morris Jesup, which is the furthest north location on Greenland, by Friday the 23rd experienced 6 C or 43 F temperatures on the shores of what should be a frozen solid Arctic Ocean just 400 miles from the North Pole.

The average high temperature in Cape Morris Jesup is -20 degrees Fahrenheit during February — making Friday’s reading a whopping 63 degrees F warmer than average. For reference, a similar departure for Washington, DC would produce a 105 degree day in February.

But it wasn’t just Cape Morris Jesup that was experiencing July-like conditions for the Arctic during February. For the expanding front of that ridiculously warm winter air by Sunday had expanded into a plume stretching tens of thousands of square miles and including a vast zone of temperatures spiking from 45 to 54+ degrees F above normal.

(The zone of pink-to-white in the above anomaly map shows temperatures ranging from 45 to 54 F [25 to 30 C] above average directly over a broad Arctic region centering on the North Pole. To this weather and climate observer, it looks like a hole in the heart of winter. Also note the region of cold air pushed south over Europe and the present above average [1981-2010] global reading. Image source: Climate Reanalyzer.)

And at the center of the warm air pulse was today’s earlier reading of 1.1 C or 34 F at the North Pole (see image at top of post). What would typically be a summer-time temperature for this furthest north location of our world happening during February. A highlight warm point in the midst of a vast plug of far warmer than normal air. A hole in the heart of winter.

We’ll wait for confirmation from experts like Chris Burt, Bob Henson, and Dr. Jeff Masters at Weather Underground, but it appears that this particular warming event — the highlight of an ongoing polar warming of the past few weeks — is without precedent in the Arctic during February. It is also an exemplar — a good example — of the kind of weather we can expect to frequent the Arctic more and more often as the global crisis that is human-forced climate change deepens and as its primary cause — fossil fuel burning — continues.

(Please also see Neven’s related excellent expert analysis of this unprecedented polar warming event at the Arctic Sea Ice Blog here. More to follow on impacts to sea ice in a developing post.)

Polar Warming Translates South as June-Like High Pressure Ridge Brings Record-Smashing Temperatures to Eastern U.S. in February

The North Atlantic and Arctic weather pattern is a real mess. Frequent episodes of severe polar warmth relative to normal conditions for this time of year have been a persistent feature. Arctic sea ice extents are at record lows. Meanwhile, the upstream atmosphere generated a record-smashing high pressure system and related abnormal warmth over the U.S. East on Wednesday.

(Severe warming, both at the surface and in the upper atmosphere over the Arctic helped to generate a polar vortex collapse during recent days. This collapse, in turn, generated a number of high amplitude waves in the Jet Stream — one of which produced a record high pressure ridge over the U.S. East Coast on Wednesday, February 21. Image source: Earth Nullschool.)

All these severe weather elements have ties to a climate change related condition called polar amplification. A condition that generates mass sea ice loss and extreme warmth at the northern pole, especially during winter. One that translates into more extreme ridge and trough patterns over the middle latitudes. And due to these features, the weather for both the Arctic and the North Atlantic doesn’t appear to be set to return to anything approximating normal for at least the next five days.

Forecast for More Extreme Warmth…

Far to the north, a long, thin extension in the Jet Stream is setting up to bring predicted above freezing temperatures to the North Pole by Sunday. The surface system anchoring that warm air invasion is a powerful low predicted to bomb out around 930 mb just off the coast of Greenland on Saturday. It will fling hurricane force winds and near to above freezing temperatures over coastal and northeastern sections of this frozen archipelago before translating that significant energy northward into the Arctic by early Sunday.

(Extreme warmth struck both the Arctic and the U.S. East on Wednesday, February 21st. A similar pattern is predicted to repeat by this weekend — pushing temperatures to near or above freezing at the North Pole even as the US southeast swelters. Image source: GFS/Climate Reanalyzer.)

Temperatures over central and northern Greenland are predicted to range between 10 and 25 C above average even as parts of the high Arctic spike to 30 C above average.

… Following Wednesday’s Record-Breaking Ridge

Though much of the recently most extreme weather action has been focused on the Arctic, the mid-latitudes have seen there fair share of climate change wrenched extremes.

Yesterday, a slot of warm air rushing northward built into a powerful ridge over the U.S. East Coast. This ridge was not any typical pulse of warm air at the surface running counter to a much cooler winter time atmosphere. It was heavy and it was tall — translating from the ground and well into the stratosphere.

So much heat generated summer-like conditions across the U.S. East. From the mid Atlantic to the northeast, temperature records last set as far back as the late 1800s were shattered. Washington DC saw 82 degree (F) temps. Vermont shattered several of its all-time record highs for February. Massachusetts saw temps hit 80 in Fitchburg. While New York’s Central Park also broke its all-time record of 68 F as the mercury struck 78 degrees yesterday. It was the strongest outbreak of heat ever to strike the northeastern section of the U.S. since record-keeping began back in the late 19th Century. Temperatures there were more typical of June and far less so of February.

All that extra heat translating so far into the upper atmosphere also generated convection and cloud formations more typical of summer — with cumulus clouds piling up over places like Atlanta.

And it wasn’t just temperatures and clouds that were increasingly trekking into outlandish parameters for February, it was the state of the atmosphere itself. For the central peak of the high pressure system provoking such powerful atmospheric anomalies was a stunning 595 dm at the 500 millibar level. This was the highest pressure ever recorded at the 18,000 foot level of the atmosphere. And the earliest time we’ve ever seen such a strong high pressure system off the U.S. East Coast previously was during June.

By the weekend, another warm air push is expected to invade the U.S. East. This time, it appears that temperatures in the Southeast will be most intense with highs hitting around 85 F across parts of Georgia and Florida even as a broad region of 75 to 80+ degree readings sweeps from the Gulf Coast on up through Virginia Sunday.

In the Context of Human-Caused Climate Change

We would be remiss if we didn’t note that increasing atmospheric thickness and powerful high pressure ridges are noted features of a warming global environment. New record high temperatures are also a climate change indicator — especially when they occur with such high prevalence and frequency. And this is the case even over the continental U.S. as a rapidly warming Arctic is helping to drive increasing hot and cold temperature extremes in the middle latitudes.

North Pole Region Predicted to Experience Another Instance of Above Freezing Temperatures as the Bering Sea Ice is Blasted Away

Those previously rare instances of above freezing temperatures in the Arctic north during winter time are happening more and more often.

(February 20 NASA satellite imagery shows Bering Sea with mostly open water as highly atypical above freezing temperatures drive far north. Note that patches of open water extend well into the Chukchi Sea. Image source: NASA.)

Just Monday and Tuesday of this week, Cape Jessup, Greenland — a mere 400 miles away from the North Pole — experienced above freezing temperatures for two days in a row. This following a February 5 warm air invasion that drove above 32 F temperatures to within 150 miles of this furthest northerly point in our Hemisphere even as, by February 20th, a warm air invasion relentlessly melted the Bering Sea’s typically frozen surface (see image above).

Far Above Average Temperatures Over Our Pole

It’s not just a case of warming near the pole itself. It’s the entire Arctic region above the 66 degree North Latitude line. Over the past few days, Arctic temperature anomalies have exceeded 6 degrees Celsius above the 1981 to 2010 baseline. A period that was already showing a serious warming trend.

(Insane levels of warmth relentlessly invade the Arctic during February — hammering the sea ice and wrecking havoc on local environments. Image source: Climate Reanalyzer.)

For reference, 6 C warmer than normal daily readings for any large region of the Earth’s surface is a very serious temperature departure. And the Arctic is clearly feeling it as it suffers the lowest sea ice extent in our record keeping. The heat is meanwhile wreaking out of control harm on the Arctic environment — endangering key species like seals, walrus, puffins, and polar bears, setting off very rapid coastal erosion as storm waves grow taller, triggering far more extensive and powerful Arctic wildfires, and causing mass land subsidence and various harmful environmental feedbacks from permafrost thaw. It’s also causing Greenland’s massive glaciers to melt faster — contributing to an acceleration in the rate of global sea level rise.

The warm air has been invading primarily from the ocean zones in the Atlantic and the Pacific. Warm storms have frequently roared north through the Barents Sea and up the Greenland Strait near Svalbard. Massive blocking high pressure systems have shoved outlandishly warm temperatures through the Bering Sea on the Pacific side day after day, month after month.

Warm Air Invasions Clear Sea Ice During Winter

A recent warm air invasion has practically cleared the Bering Sea of ice. And the ice edge there is further withdrawn than it has ever been in its history. As we can see from the below animation, this crazy and rapid clearing of ice continues to drive further and further north — ushered in by a relentless invasion of warm air — during February. A time when Bering ice should be expanding, not contracting.

What’s causing such extreme polar weather? In two words — climate change. But drilling down, the details can actually get pretty complicated.

During recent winters, human-caused climate change has been driving temperatures into never-before-seen ranges over our northern pole. Increasingly, Sudden Stratospheric Warming events have been propelling warm air into the upper layers of the atmosphere. The Polar Vortex, which during winter relies on a column of sequestered cold air to maintain stability, is blown off-kilter as these upper level layers heat up. This, in turn, has generated extreme wave patterns in the winter Northern Hemisphere Jet Stream — enabling much warmer than usual temperatures to rocket northward.

An Ongoing Series of Warming Events

On December 30 of 2015, and enabled by a high amplitude Jet Stream wave, a powerful warm storm event pushed a strong wedge of warm, above freezing, air all the way across the 90 North Latitude line. Meanwhile, Jessup Greenland hit above freezing for what was likely the first time ever over the past two winters. Last year’s Arctic sea ice hit the lowest levels ever seen during March due to all the extra heat. And the warm temperature extremes appear to be deepening.

Now, as of mid February, a powerful Sudden Stratospheric Warming Event has again blown the Polar Vortex off kilter — weakening it and enabling warm air to flood into the Arctic even as colder air is displaced southward over Canada, the Western U.S. and Europe. Translating to the surface, this train wreck in the upper level winds has driven the extreme polar warming events of the past 8-10 days even as cold air invasions have overtaken Europe and the U.S. East experiences record-breaking heat.

The polar warming event is still ongoing. And it is expected to deliver another blow to an Arctic environment that typically experiences -30 degree Celsius temperatures this time of year. For another major warm wind invasion is forecast to drive above freezing temperatures over the North Pole by this weekend. Strong south to north winds along an extreme ridge in the Jet Stream are predicted to push 1-2 C temperatures (or approximately 55 F above average temps) over the North Pole on Saturday and Sunday.

(High amplitude Jet Stream wave predicted to drive North Pole temperatures to above freezing by Sunday. Image source: Earth Nullschool.)

Though rare during December, above freezing temperatures at the North Pole during February are practically unheard of. The period of February through April should be a time of strengthening and thickening ice ahead of melt season. But during 2018 this appears not to be the case. The ice instead, in key regions, is being delivered with serious setbacks which is greatly retarding this year’s typical Arctic Ocean ice formation.

If this most recent polar warming event emerges as predicted, it will provide yet one more powerful blow to an already greatly weakened Arctic sea ice pack during a time of year when extents and areas should be reaching their peak. And that’s bad news for both the Arctic and global environments.

Arctic Sea Ice Extent at Record Lows as Winter Temperatures Soar

Five point five degrees Celsius above average.

That’s how much warmer than ‘normal’ the entire region of the Arctic above the 66 degree North Latitude Line was earlier today. Areas within this large warm pool saw temperatures spike to a range of 15 to 25 C warmer than the already warmer than normal 1981-2010 base period. And broad regions saw temperature between 10 and 20 C above that 30-year average.

(The entire Arctic is an incredible 5.5 C warmer than normal today. Meanwhile, Arctic sea ice extent has plunged, once-more, into record low ranges. Image source: Climate Reanalyzer.)

It’s just a snapshot. But day after day, week after week, month after month, the story has been much the same throughout Fall and Winter of 2017-2018.

And as during last year’s ridiculously warm Arctic winter, the sea ice has taken a considerable pounding. Yesterday dropping to a new record low extent of 13.774 million square kilometers. Beating out the previous record low for the day set just last year. And dipping more than 1.8 million square kilometers below the 1979-1990 average. A period that already featured greatly reduced Arctic sea ice cover when compared to extents seen in the early 20th Century.

(Arctic sea ice extent for 2018 [lower pink line above] dipped into new record low ranges during recent days. Note that the 1979 – 1990 extent average is indicated by the green line at top. Image source: NSIDC.)

The primary cause of these ice losses is warming both of the ocean and of the air. And, as we can see in the ongoing trend, the Arctic is getting more than its fair share of both. Such polar amplification is a direct upshot of the massive volume of harmful greenhouse gasses being injected into the atmosphere through fossil fuel burning. And we are seeing the dark fruits of that burning now in the massive and ongoing winter losses of sea ice, the harm to various Arctic life forms like puffins and polar bears, and the risk of increasing sea level rise, ocean circulation destabilization, and increasingly extreme weather events that all result from the heating-up of polar environments.

Extremely Warm Cyclone Predicted to Drive 50-60 F Above Average Temperatures Across North Pole

Our lexicon of what’s considered to be normal weather does not include February days in which temperatures at a North Pole shrouded in 24-hour darkness cross into above freezing ranges. But that’s exactly what some of our more accurate weather models are predicting will happen over the next five days.

Another Unusually Warm and Powerful Storm

During this time, a powerful 950 to 960 mb low is expected to develop over Baffin Bay. Hurling hurricane force gusts running from the south and digging deep across the North Atlantic, Barents, and Arctic Ocean, the low is projected to drive a knife of 50-60 F above average temperatures toward the North Pole by February 5th.

(20-25 foot surf heading for the increasingly fragile sea ice in this February 4 wave model forecast. Note the 30-40 foot waves off Iceland and associated with the same storm system that is predicted to bring above freezing temperatures to the North Pole on February 5th. Image source: Earth Nullschool.)

These warm winds are predicted to bring above freezing temperatures to areas that typically see -20 to -30 F readings in February. They are expected to rage over a sea ice pack that is at record low levels. And if the storm emerges, it will hammer that same dwindling ice pack with 20 to 25 foot or higher surf.

Fragile Arctic Sea Ice Faces a Hammering

Presently, Arctic sea ice extent is trending about 200,000 square kilometers below record lows set just last year for the period of late February. And recent scientific research indicates that warm winter storms like the one that is now predicted to form can have a detrimental impact on sea ice.

(Arctic sea ice extent is presently at around 13 million square kilometers [bottom red line] — a new record low for this time of year. It should be around 15 million square kilometers and would be if the world hadn’t warmed considerably since the 1980s. Image source: JAXA.)

Not only do the storms bring warmer temperatures with them — a kind of heat wave that interrupts the typical period of winter freezing — they also drive heavy surf into a thinner and weaker ice pack. The surf, drawn up from the south churns warmer water up from the ocean depths. And the net effect can dissolve or weaken large sections of ice.

The presently developing event is expected to begin to take shape on February 4th, with warm gale and hurricane force winds driving above freezing temperatures near or over the North Pole on February 4th – 6th. To say that such an event, should it occur, would be practically unprecedented is the common understatement of our time. In other words, this is not typical winter weather for the North Pole. It is instead something we would expect to see from a global climate that is rapidly warming and undergoing serious systemic changes.

(February 5 GFS model run shows above freezing temperatures crossing the North Pole. Temperatures in this range are between 50 and 60 degrees [F] above average for this time of year. If the extremely warm cyclone event occurs as predicted, it will be a clear record-breaker. It will also further harm Arctic sea ice levels that are already in record low ranges. Image source: Climate Reanalyzer.)

Extreme Cyclone Beneath an Extreme Jet Stream

In the predicted forecast we see more of the extreme jet stream waves that Dr. Jennifer Francis predicted as an upshot of human-forced polar amplification (a condition where the poles warm faster than the rest of the globe under a larger warming regime). The particular wave in question for the present forecast involves a high amplitude ridge running very far to the north over Svalbard and knifing on into the high Arctic. The facing trough over Baffin Bay, Greenland, and North America is also quite pronounced and elongated. A feature that appears to want to become a cut off bubble of displaced polar air in a number of the model forecasts.

High amplitude Jet Stream waves during Northern Hemisphere winter as a signature of global warming are predicted by Francis and others to generate greater temperature and precipitation extremes in the middle latitudes. They are a feature of the kind of stuck and/or upside down weather we’ve been experiencing lately where temperatures in the Northeast have been periodically colder than typically frigid locations in Alaska. These flash freezes have, at times, faded back into odd balmy days in the 50s and 60s (F) before plunging back into cold. But the overall pattern appears to get stuck this way for extended periods of time.

(Very high amplitude ridge and trough pattern at the Jet Stream level of the circumpolar winds is thought by a number of scientists to be a feature of human caused global warming. One that is related to polar amplification in the Arctic. Image source: Earth Nullschool.)

Heat in the Arctic is driving sections of cold air south even as warm air invades through places like Alaska, Northeast Siberia, and the Barents Sea. But the main variables of this story are global heat, global warming, fixed extreme temperature and precipitation patterns, and warm air invasion. The winnowing streamers of cold air driven out over places like the U.S. Northeast are just a side effect of the overall warming trend. One that is starkly apparent in the very odd western warmth that has grown more and more entrenched with each passing year.

For Now, It’s Still Just a Forecast

As with any five day forecast, we can take this one with more than just a grain of salt at the present time. But such an extreme event is entirely possible during the present age of human-forced climate change. During late December of 2015, we identified a predicted major storm that ultimately drove North Pole temperatures to above freezing. At the time, that storm was considered unusual if not unprecedented. However, since February is typically a colder period for the North Pole region, a warm storm drawing above freezing air into that zone would be even more unusual. It would also be a feature of the larger trend of loss of typical seasonal winter weather that we’ve been experiencing for some time now.

5 FEB UPDATE: Storm and Heat a Bit Further South and East Than Predicted

A powerful warm storm in the 952 mb range did form and track across Greenland to exit over the Greenland Strait earlier today. The storm drove warm air far north, pushing above freezing temperatures past Svalbard and over the dark and frozen sea ice. It hurled gale force winds, hurricane gusts, and massive swells into the ice. But it did not push temperatures to above freezing at the North Pole as some models had earlier predicted.

(Warm cyclone hurls much warmer than normal temperatures across the Barents Sea and Arctic Ocean on 5 Feb, 2018. Image source: Earth Nullschool.)

It did, however crank temperature there up to -4.3 C or about 26 C above average for this time of year.

The storm is now predicted to drive above freezing temperatures across the Barents Sea, over Novaya Zemlya, through the Kara Sea and ultimately into Northern Siberia over the next 24-48 hours. In numerous regions, temperatures are already hitting near 30 C (54 F) above average. This extremely warm spike relative to typical conditions — associated with a high amplitude Jet Stream wave and related cyclone — will continue to ripple through the Arctic over the next few days.

Overall, total Arctic region temperature anomalies are predicted to range from 2.5 to 3.5 C above the 30 year average for the next few days. These are very warm departures. But not so warm as recent spikes in the range of 4 to 5 C above average for the region. In addition, there appears to be a tendency for powerful warm storms to continue to develop near Svalbard in the longer 5-15 day model runs. So the North Pole isn’t out of the woods yet for potential above freezing temperatures this February.

A Visibly Extreme Jet Stream in Advance of Irma

On Tuesday, I wrote this blog about how Jet Stream behavior and related severe weather during summer of 2017 jibed with the findings of recent climate science. About how human-forced polar warming appears to be impacting extreme summer weather patterns by altering the upper level winds — with a particular focus on impacts to North America.

Yesterday, I looked at the upper level wind patterns running over North America in advance of Irma’s approach and saw this:

(Classic ridge-trough pattern like that identified by Dr Jennifer Francis and Dr Michael Mann. One that, according to their related research, increases the likelihood of certain kinds of extreme weather patterns and events. One that these scientists associate with polar warming set off by human-caused climate change. Image capture from 1500 UTC on September 6. Image source: Earth Nullschool.)

It’s a classic high amplitude wave form in the Jet Stream. One that shows an extremely deep trough digging all the way down to the Gulf Coast in the east and arching back up into a pointed ridge north of Alaska and into the Arctic Ocean in the west. This kind of high amplitude wave pattern is not typical. Or if such a pattern did appear in the past, it tended not to stick around for so long. But during this summer, such intense high amplitude ridges have been forming again and again over the west and such deep troughs have been forming again and again in the east.

New Precipitation and Temperature Extremes

The most apparent visible effect of this ridge-west — trough-east pattern has been to produce record heat, drought, and wildfires in the west and record rainfall in conjunction with an extremely stormy weather pattern in the south and east. You can plainly see this dipolar relationship in the precipitation and temperature anomaly maps provided by NOAA below:

These maps cover precipitation and temperature observations for the last 30 days compared to climatological averages. In the west we find that precipitation for large regions has been less than 10 percent of normal (less than 1/10th normal). Meanwhile temperatures in the west have ranged between 1 and 4 C above average. In the south and east, large regions have seen between 200 and 800 percent of typical precipitation amounts (2 to 8 times the norm). Temperatures, meanwhile have ranged between 1 and 3 C below average.

This is the very definition of heightened extremes. Looking at the prevalent upper level air pattern over the U.S. for the summer of 2017, it’s clear that south to north upper level winds pulling air up from the Equatorial zone toward the pole are facilitating one side of the extreme and that a countervailing upper level wind originating near the pole and running south toward the tropics is driving the opposite extreme.

Slowing Upper Level Winds in a North-South Orientation Weakens the Steering Currents

Unfortunately, prevalent and long lasting heat or heavy rainfall isn’t the only apparent impact of this new pattern. Another aspect of this extreme dipole is a weakening of the west to east steering currents that typically begin to pick up in a region between 25 and 30 degrees North Latitude and to intensify further beyond the 30 N line. This effect is due to the fact that upper level wind patterns are oriented more in a north-south (west) or south-north (east) direction and due to the fact that under such large Jet Stream meanders the upper level steering winds tend to slow down.

(It’s not just Harvey and Irma. Weak upper level steering currents are contributing to a long range potential that Jose might loop back to strike South Florida.)

For Hurricanes like Harvey and Irma, stronger west to east steering winds have had two protective effects for the United States. First, they have helped storms to keep moving — working to generally prevent the kind of long duration stall we saw that helped to produce such catastrophic flooding during Harvey. Second, they have tended to deflect storms away from the U.S. East Coast. And for Irma, what this means is that this storm is more likely to strike the U.S. East Coast if the upper level steering winds that would typically turn it to the east are weak.

This is a dynamic upstream aspect of human-forced polar warming. One that produces added extreme weather risks on top of those already generated by warming ocean waters — which increase peak potential storm intensity — and rising atmospheric water vapor — which helps to add latent heat, lift and related convective available potential energy that increases top limits for storm intensity and heavy rainfall.

And as we sit here hoping and praying that Irma will re-curve away from the U.S. east coast, we should consider how polar warming may be helping to make such a terrible strike more likely — increasing risks to so many people and to so much that we all hold dear.

RELATED STATEMENTS AND INFORMATION:

Links:

Dr Jennifer Francis

GFS Model Runs illustrated by Earth Nullschool

Extreme Weather Events Linked to Climate Change’s Impact on Jet Stream

This is the Pattern Climate Scientists Warned us About

NOAA

Hat tip to Scott

Hat tip to Wharf Rat

This is the Climate Pattern Scientists Warned Us About — Wildfires Approach 8 Million Acres in U.S. During Summer of Extreme Western Heat, Severe Eastern Storms

“If the same weather persists for weeks on end in one region, then sunny days can turn into a serious heat wave and drought, and lasting rains can lead to flooding.” — Dr. Stefan Rahmstorf.

“The warming of the Arctic, the polar amplification of warming, plays a key role here. The surface and lower atmosphere are warming more in the Arctic than anywhere else on the globe. That pattern projects onto the very temperature gradient profile that we identify as supporting atmospheric waveguide conditions.”Dr. Michael Mann.

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To say that, for the U.S., it’s been hot out west and stormy in the east this summer is a bit of an understatement. For while the east has seen numerous storms producing local-to-national record rainfall amounts, the west has been baking under heatwaves that appear to have set off one of the worst years for wildfires nationally on record. This is an extreme summer weather pattern that recent scientific studies have linked to human-caused climate change.

(Severe western wildfires blanket northern U.S. under a massive plume of smoke. Image source: NASA Worldview.)

Last week, extreme heat baked the U.S. west coast. On Friday, San Francisco hit a record high of 106 degrees (F), striking up to 102 (F) on Saturday. Regions further inland near Eureka hit a Death Valley-like 115 F.  36 million Californians fell under a heat advisory as excessive heat warnings ranged on up the west coast through Oregon, Washington, and British Columbia.

The heat wave — which was just the most recent of many for the region this year — baked hills and valleys covered with new vegetation springing up after unusually heavy winter rains. Setting off a spree of wildfires that has seen very severe burn rates throughout summer.

Los Angeles County in Burbank experienced its largest fire on record Saturday as a massive blaze swept through the hills — igniting 7,000 acres before being tamped down by the oddly northward tracking remnants of a tropical storm drifting through the region on Sunday.

The fire spurred the response of 1,000 firefighters, forced 700 people to evacuate, closed route 210 for a time and consumed three homes. Assisted by the rains and moisture flowing off the remnants of Lidia, firefighters have now managed to contain 30 percent of this particular blaze. But with many more fires continuing to burn throughout the west, the region is far from out of the proverbial woods.

According to the National Interagency Fire Center, 70 large fires continue to burn in the western states of Montana, California, Oregon, and Washington. The vast majority of these fires remain uncontained. And at least two exceed 100,000 acres in size. Smoke from these fires has been cycling into the upper level winds for some time now — with most of the northern U.S. falling under a high altitude smoke plume (see top image above).

In total, more than 7,800,000 acres have burned so far in the U.S. this year. This represents the second worst fire year on record so far compared to the last ten years and may ultimately beat out 2006 as the second worst fire year ever recorded. By end 2006, 9 million total acres had burned. During the worst fire year for the U.S. — 2015 — 11 million acres burned in total. By this time during 2015, nearly 9 million acres had been consumed compared to 2017’s present total near 8 million acres.

These fires are occurring primarily in the west where a persistent high amplitude ridge in the Jet Stream has formed. This ridge keeps enabling heatwaves to bake the region and spike fire dangers. And it’s a weather feature that some scientists are saying is linked to human-caused climate change — which is causing the Arctic to warm, while pulling meridional south-to-north upper level winds into the polar zone and producing a wavier jet stream during extreme weather patterns.

(A study produced by a team of scientists including Dr. Michael Mann in March linked extreme summer weather patterns to polar warming and a wavier jet stream.)

The net effect is to create a kind of Halo of Storms and Heatwaves over the middle and upper latitude regions of the world. Earlier this year, The Scientific American noted:

What we think happens is that when there is a ridge forming in a location where Arctic warming can intensify it, that makes the ridge strong and builds it even farther northward. It creates an even bigger wave in the jet stream. You get a stronger ridge over western North America and a stronger southward dip that is farther toward eastern North America.

A subsequent scientific study lead by Dr. Michael Mann and presented in March of this year found that:

… analysis of both historical model simulations and observational surface temperature data, strongly suggests that anthropogenic warming is impacting the zonal mean temperature profile in a manner conducive to wave resonance and a consequent increase in persistent weather extremes in the boreal summer.

And this is exactly what we’ve seen over the U.S. this summer. A stronger than normal ridge in the west fueling record heatwaves and wildfires and a stronger than normal trough in the east fueling more extreme storms. This is a pattern of juxtapposed extremes. One that appears to be fueled by climate change related factors.

Links:

NASA Worldview

National Interagency Fire Center

Largest Wildfire in Los Angeles History Burns Amid Record-Setting Heat

The Arctic is Getting Crazy

Extreme Weather Events Linked to Climate Change’s Influence on the Jet Stream

A Halo of Storms and Heatwaves

Arctic Air Temperatures are Set to Hit 35 to 55 F Above Average by Thursday — Out of Season Sea Ice Melt Possible, Again

“It looks like a triple whammy – a warm ocean, a warm atmosphere, and a wind pattern all working against the ice in the Arctic.”NSIDC director Mark Serreze.

“Unfortunately, Arctic sea ice extent growth has once again slowed this week…”Zack Labe

“Huge surface air temperature anomalies over the Arctic this working week… over 25C warmer than average in parts.” — James Warner

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This year, it’s a challenge to find a time when the Arctic Ocean has ever represented anything resembling normalcy. Record low sea ice extent values have occurred for more than 50 percent of days measured. And well above average temperatures have invaded the Arctic during winter, spring, and fall. With another huge wave of ridiculous warmth building up over eastern Siberia this week, the hits just keep on coming.

Major Warming Over Siberia, Chukchi and East Siberian Seas 

The present big warm air invasion has its origins in the Pacific Ocean. There, a large high pressure system over the Bering Sea is facing off with a strong low moving up across Kamchatka. Running between the two is a powerful south-to-north wind pattern.

image

(A major warm wind invasion of the Arctic on Thursday is originating in the subtropical Pacific. A ridge in the Jet Stream extending all the way to the North Pole is pulling this big bulge of warm air north. As a result, extreme temperature departures and out of season sea ice melt for the impacted zones are likely. Image source: Earth Nullschool.)

As we can see in the image above, the flood of warm air has its origin around the 30 north latitude line. It flows directly over hundreds of miles of ocean, at times reaching a storm-force intensity near 70 mph. As it crosses into Siberia, the wind slows down. But it inexorably continues north, ever north — driven on by a serious pulse of atmospheric steam. By early Thursday, the leading edge of this warm air outburst from the Pacific side will have crossed the Pole and led to a flushing of Central Arctic air out into the Barents Sea and North Atlantic (you can view an animation of the predicted warm air pulse here).

This strong northward flood of warmth from the Pacific is running up under an extreme high amplitude wave in the Jet Stream that is bellowing out into the Arctic Ocean through the Bering and Chukchi seas. At its peak northward extent, the big Jet Stream wave is predicted to look something like this. And it is this severe contortion in the upper level wind pattern that has enabled this most recent extreme warm wind event to occur.

This pattern is now in the process of injecting above-freezing air temperatures into Eastern Siberia. By tomorrow, the warm air mass will encounter the coastal regions of the Chukchi and East Siberian seas. There, it will push temperatures as high as 2.5 C  (37 F) over zones that typically see readings in the -20s to -30s (Celsius). As a result, temperatures will range between 20 and 30 C (35 to 55 F) or more above average for many locations.

severe-arctic-warming-again

(Climate Reanalyzer has added a new color — white — for tracking extreme departures in temperature. In the positive anomaly column, we find departures hitting 30 C, or 54 F, above average for regions of East Siberia and the local Arctic Ocean.)

To be clear, these temperatures are highly abnormal. If a similar temperature departure happened in Gaithersburg, Maryland on December 8, it would produce 80 to 100 degree (F) readings. Of course, this anomaly is not happening in Gaithersburg. Due to a global warming related process called polar amplification in which the poles are more sensitive to alterations in rising greenhouse gas levels (due to fossil fuel and related emissions), extreme temperature anomalies tend to occur at the poles as rates of relative warming are 2-3 times faster in those regions. And the factors that we observe associated with this new Arctic warm wind event — powerful south-to-north meridional air flows coupled with extreme high amplitude waves in the Jet Stream — are also evidence of a number of weird new atmospheric circulation patterns that can tend to pop up as polar amplification intensifies.

Warm Winds May Cause Unprecedented Back-to-Back Fall Sea Ice Melt

The Pacific side of the Arctic has already been gaining heat ahead of the oncoming warm wind event over the past few days. And what we have seen, as a result, is a pretty severe loss of ice in the Chukchi Sea during early December. To be very clear, Arctic sea ice should be advancing at this time of year. But what we see in the image below (provided by A-Team over at the Arctic Sea Ice Forum) is advance followed by retreat as the warm wind event starts to ramp up.

chukchi-20-nov-06-dec-2016-side-by-side-ice-amsr2-conc-and-smos-thickness

(Ice refreeze in the Chukchi advances until it is rolled back by the most recent onrush of warm air flowing in from the Pacific. Image provided by A-Team at Neven’s Arctic Sea Ice Forum.)

Of course, the retreat seen above has occurred before the main force of warm southerly winds — due to hit the Arctic Ocean region by tomorrow. So the risks for continued losses in the Chukchi extend for at least the next few days. Losses there could be offset by large enough gains elsewhere to continue an overall seasonal freeze trend. But so far, with abnormal warmth also periodically building in over the near-Svalbard region and with Hudson Bay refreeze continuing to lag, that does not appear to be happening.

Looking at the larger monitors, we also find that, as happened during October and November, the pace of overall sea ice growth has stalled. According to JAXA, over the past 4 days, sea ice extent has only grown by 50,000 square kilometers. During a typical similar four day period for this time of year, growth would tend to average around 400,000 to 500,000 square kilometers. And with values at current record low levels, the inertial impetus for ice growth would be higher. That is, unless the climate state of the Arctic has radically changed — which appears to be the case.

arctic-sea-ice-extent

(According to JAXA, Arctic sea ice extent has again hit a plateau when it should be freezing — this time at around 10 million square kilometers. As sea ice follows that line, record lows are again deepening — hitting near 750,000 square kilometers below previous lows for the day in 2006. Considering the fact that another major warming event is building into the Arctic Ocean, this plateau could again tip into melt as happened during the middle of November. Image source: JAXA.)

During mid November, a period of unprecedented warming produced an almost unprecedented period of fall melt. A similar November melt occurred during 2013. But the amount of melt then was smaller. And that melt did not occur at a time when Arctic sea ice values were at new record lows — as they were throughout the entire month during 2016. Similarly, during October, abnormally warm conditions produced an odd re-freeze plateau similar to the one we are now experiencing.

Given current conditions, there’s a risk that we could see a December melt event following the November melt event. For the amount of heat hitting the Pacific side of the Arctic is predicted to fall far outside of normal temperature ranges. And, barring major refreeze on the Atlantic side, we are at a rather higher risk of seeing the present plateau in sea ice values carry on for a number of days.

Links:

The National Snow and Ice Data Center

Earth Nullschool

Climate Reanalyzer

The Arctic Sea Ice Forum

JAXA

Sea Ice Extent Hit Record Lows in November

Dr Jennifer Francis on Jet Stream Changes

Hat tip to John Allen

Hat tip to Neven

Hat tip to A-Team

Hat tip to Ryan in New England

As a Titanic El Nino Begins to Fade, What Fresh Trouble Will a Record Warm World Bring?

Today the globe is feeling quite a bit of backlash from a human-warmed sea surface and atmosphere. As it ends up, Dr. Kevin Trenberth was right. Deep ocean warming set off by heat-trapping fossil fuel emissions and building up through the first two decades of the 21st Century did re-surge from the depths to haunt us in 2014, 2015 and 2016. In that wrenching global climate system shift to the hot side of natural variability, a titanic El Nino emerged. It was one of the top three strongest such events in the modern record. One that by NOAA’s measure appears to have tied the extreme event of 1998 at its peak intensity.

ONI sea surface temperature anomalies in Nino 3.4

(Sea surface temperature departure from average in the benchmark Nino 3.4 zone shows surface ocean heat anomalies for the 2015-2016 El Nino equaled peak 1997-1998 values. Image source: NOAA/CPC.)

Expected Heat, Drought, and Storms Together With a Few Ominous Surprises

This event did push the world into extreme warmth even as predicted related severe weather flared in some of the typical regions. Annual average global temperatures rocketed to about 1.06 C above 1880s baselines during 2015 even as monthly departures hit 1.2 to 1.3 C or more higher than the same benchmark during December and January.

Amidst this great upheaval of global heat, the world also experienced yet one more wave of freak droughts (this time over Northern South America, the Caribbean, large swaths of Africa and Southeast Asia), heat-related mass casualty events, floods, and strongest hurricanes on record. Arctic and global sea ice measures are once again plunging to new record lows. A global coral bleaching event, perhaps the worst such instance ever experienced, was also set in motion.

The predicted patterns and potential worse-case events (such as heatwave mass casualties, coral bleaching, and sea ice loss) were also contrasted by a number of surprises. The first and perhaps most ominous was the failure of El Nino to bust the California drought. Though the West Coast of the US did experience a number of storms, the pattern was more typical of normal Winter moisture for the Northwestern US even as drought continued throughout the Southwest.  Moisture instead tended to split fire-hose fashion — with storms either cycling northward into Alaska, the Aleutians, or the Bering Sea, or south over Southern Mexico or Central America, up across the Gulf and on out into a particularly severe storm zone forming in the North Atlantic.

30 day precipitation anomaly shows southwest drought continuing

(Over the last 30 days the southwest drought re-emerged as a blocking pattern again began to take hold over Western North America and the Eastern Pacific. Image source: NOAA/CPC.)

This continued loss of moisture for the US Southwest despite a record El Nino is particularly apparent in the Climate Prediction Center’s most recent precipitation anomaly measure for the last 30 days. Here we find that large parts of Central and Southern California have received just 10 to 50 percent of typical rainfall for this period. Coupled with 1-3 C above average temperatures for the month, this loss of rainfall during what would typically be California’s wettest period has come as a disappointment to many who were hoping a strong El Nino would help break the state out of a crippling drought. Now, the window for late Winter and early Spring rains is starting to close even as the blocking pattern appears to be strongly re-established in both the present weather pattern and in the forecast model runs.

But perhaps the biggest surprise coming from this El Nino year was a set of weather events in the North Atlantic that were likely more related to climate change. There, severe storms hammered a flood-beleaguered UK as a greatly distorted Jet Stream heaved Equatorial heat and moisture northward — rushing it up over a ridiculously warm and apparently backed-up Gulf Stream before slamming it on into a likely Greenland ice melt-outflow related cool pool. There the heat and moisture collided with cold to produce the epic storms that then vented their fury upon the UK.

Warm Arctic Storm

(December 29th saw temperatures rise above freezing at the North Pole — the first time temperatures have warmed so much for this high Arctic region so late in the year. Image source: Earth Nullschool.)

During one such event, a daisy chain of heavy-hitting North Atlantic lows hurled high winds, heavy rains and epic surf at the UK even as the meridional flow set up by these powerful beasts shoved above-freezing temperatures all the way to the North Pole during late December. Yet one more unprecedented and unexpected event during a record warm year. One that looks more like a human forced warming which has overcome the traditional influences of El Nino, rather than an El Nino related impact in itself.

As El Nino Fades, Equatorial Heat Tends to Move Pole-ward

Though we may see these two events — the failure of El Nino to provide heavy rains to the US West Coast, and the massive northward pulses of storms, heat and moisture hitting the North Atlantic — as unrelated, the twain patterns appear to be linked to an ongoing polar amplification. Overall, heat within the Arctic has tended to weaken the Northern Hemisphere Jet Stream over these two zones. And even during El Nino, when the Jet would have typically strengthened, we have continued to see high amplitude wave patterns forming over these regions.

But as El Nino weakens and the Equator cools, the Jet Stream would tend to slow even more. Such an atmospheric state would tend to further exaggerate already significant Jet Stream wave patterns — transferring still more low-Latitude heat poleward. In addition, the ocean gyres tend to speed up as El Nino fades or transitions to La Nina. The result is an amplified pulse of warmer waters emerging from southern Latitudes and entering the Arctic.

It’s for these combined reasons — tendency to amplify south to north atmospheric heat transfer into the Arctic post El Nino and tendency to flush warmer waters toward Arctic Ocean zones during the same period that it appears we are entering a high risk time for potential new sea ice melts and possible related Greenland land ice melts during 2016 and 2017.

Hot Blobs

(Northeastern Pacific Hot Blob remains at high intensity even as its size is predicted to expand through July. Meanwhile, very warm sea surface temperatures are predicted to remain in place off the Eastern Seaboard. The net effect of these two hot blobs may be to shove the Jet Stream far northward over North America during the summer of 2016 — potentially increasing the risk of widespread and potentially record heat and drought. Predicted very warm sea surfaces in the region of the Barents and Greenland seas — in excess of 3 C above average for a large region — is also cause for concern. This is not only due to risk for sea ice loss through this zone, but also due to its potential to set off blocking pattern and heat dome formation over Eastern Europe and Western Russia. Image source: NOAA/CFS.)

In addition, we are at serious risk of seeing the high amplitude blocks and wave patterns re-establish and persist, especially in the zone over Western North America were a related Northeastern Pacific Hot Blob is expected to restrengthen as El Nino fades. In fact, large regions of the US may fall under record to near record heat and drought this summer due to the combined influences of two very warm ocean zones surrounding her shores. Models now indicate a particular late spring drought risk for the Great Lakes region as well as an extended period of far above average temperatures for pretty much all of the Continental US during summer. Meanwhile, predicted above average spring-time precipitation for the Southwest appears less and less likely to emerge.

Finally, extreme above average sea surface temperatures are predicted to intensify over the Barents and Greenland seas through to end of Summer 2016. This is an area to watch. The added ocean heat would tend to pull the Jet Stream northward over Eastern Europe and Western Russia — generating risk of heatwaves and drought for this region even as Central Asia fell under risk of floods. Long range CFS precipitation and temperature model runs for Europe have not yet picked up this risk. However, given the intensity of heat predicted for Barents sea surfaces and the related tendency of warmth over oceans and in the far north to influence the formation of blocking patterns, heat domes, and high amplitude troughs, it’s worth keeping a weather eye on the situation.

El Nino to Weaken and Then Return; or is a Shift to La Nina Now Under Way?

Related to a polar and ocean warming-enhanced tendency to generate high amplitude Jet Stream waves — as well as associated persistent heatwaves, droughts, and floods — is the heat balance of the Equatorial Pacific. Strong El Ninos, or even a tendency to remain in or near an El Nino state, has historically aided in the breaking of new record global high temperatures when linking up to the greenhouse gas warming trend. Meanwhile, the shift toward La Nina has tended to enhance a range of global heating related issues including record rainfall events and large injections of heat toward the poles in the drop off from El Nino to La Nina.

The cause for increased risk of major precipitation events is due to the fact that El Nino is providing a massive moisture bleed into the atmosphere at times of peak intensity. With the current El Nino topping out near record levels and with global temperatures at above 1 C higher than 1880s averages, global atmospheric moisture levels are hitting new record highs at this time. If global temperatures subsequently drop by around 0.1 to 0.2 C during a transition into La Nina (into a range about 0.9 to 0.8 C hotter than 1880s values) then the atmosphere will be unable to keep a larger portion of that extra moisture in suspension and it will fall out as precipitation — primarily wringing out where the major trough zones tend to set up. We should be very clear here in saying that the drought risk related to a global warming intensification of ridge and heat dome formation is not reduced during such instances — just that the risk of extreme precipitation events is enhanced.

Russian Heatwave Pakistan Floods Jet Stream

(During 2011, as the 2010 El Nino faded into La Nina conditions, a high amplitude wave in the Jet Stream set off record heat, drought and wildfires over Russia even as Pakistan was hit by a month-long deluge that was the worst rainfall event for the region in the last 1,000 years. La Nina’s tendency to wring excess water out of the atmosphere can enhance the risk for such events to occur in a warming climate state. Image source: NASA.)

As for risks to sea ice, we’ve provided some of the explanation above. However, it’s also worth noting that the mobility of heat poleward tends to be enhanced during the periods when El Nino drops off toward La Nina. During these times, Equatorial heat tends to propagate in wave fashion toward the Poles — especially toward the Northern Hemisphere Pole which has already lost its strong Jet Stream protection warding away warm air invasions.

These two factors are major issues when considering whether La Nina or an ENSO Nuetral state will appear post El Nino during 2016. But there is a third — rate of global temperature rise. Though the primary driver of global warming is a massive human fossil fuel emission, the response of the world ocean system can significantly wag the rate of atmospheric temperature increases on a decadal time scale. If the ocean tendency is for La Nina, this would tend to somewhat suppress the overall decadal rate of temperature increase — and we saw this during the 2000s. But if the ocean tendency is to produce El Ninos (in a switch to a positive Pacific Decadal Oscillation, as appears to be happening now), then the overall pace of global atmospheric temperature increase would tend to be enhanced.

La Nina Emerges

( IRI/CPC consensus model runs show a drop off to a weak La Nina by late in the year. However, CFS model runs [image below] have shown a tendency to predict a resurgence of El Nino conditions by Fall. Image source: NOAA/CPC.)

To this point we find that the official model forecast consensus published by NOAA (IRI/CPC figure above) shows a transition to ENSO neutral states by May, June, and July which then proceeds on to a very weak La Nina by Fall. In such a drop off, we would likely still see record global high temperatures during the period of 2016 (in the range of 1.03 to 1.15 C above 1880s values).

However, the late 2016 and 2017 tendency for temperatures to recede from new record highs would be somewhat enhanced (likely dropping below the 1 C above 1880s mark in 2017 or 2018 before again making a challenge to the 2015-2016 record with the potential formation of a new El Nino in the 3-5 year time-frame of 2019 through 2021). It’s worth noting that this scenario shows an increased risk of a stronger warm air pulse heading toward the Northern Polar zone together with added fuel for extreme precipitation events as global temperatures would tend to drop off more swiftly from late 2015 and early 2016 peaks.

El Nino Continues

(CFSv2 model run — shows El Nino continuing on through the end of 2016. Over recent months, the CFSv2 series has shown a high accuracy. However, NOAA’s current forecast preference is for the IRI model set predictions [previous image above]. Image source: NOAA/CPC.)

In contrast, the CFSv2 model forecast from NOAA (above image) shows El Nino only weakening through to July and then re-strengthening in the October-November time-frame. This CFS model scenario would result in higher atmospheric temperatures in 2016 — practically guaranteeing a lock on an unprecedented three back-to-back-to-back record warm years for 2014, 2015, and 2016. But such a scenario — implying that the Pacific Ocean had entered a new period of El Nino tendency — would also tend to keep atmospheric temperatures nearer to the newly established record highs.

Under the CFSv2 scenario, we may expect annual average global temperatures to rise as high as 1.08 to 1.2 C above 1880s values during 2016 (a very extreme departure and one uncomfortably close to the 1.5 C warming mark). These extreme values would, perhaps, recede to around between 0.9 and 1.1 C during 2017 so long as the second El Nino pulse did not remain in place for too long. However, if the bounce back toward El Nino conditions was strong enough in late 2016, there would be an outside chance that the globe may experience not 3, but an absolutely obnoxious 4 back-to-back record warm years.

NASA temperature trend

(During 2015 global annual temperature rocketed to above 1 C hotter than 1880s values. There’s at least an even chance that 2016 will be hotter still. Considering the considerable heating tendency imposed by a fossil fuel-forced warming of the world, how much worse can it get during the 21st Century’s second decade? Image source: NASA GISS.)

Meanwhile, the warm air pulse heading toward the poles may be somewhat muted under this scenario. A statement that should be qualified by the fact that we’ve already seen a substantial amount of El Nino heat heading poleward during the present event. In addition, potentially heavy rainfall events may not receive the added oomph of a decent global temperature drop to wring out more moisture. A statement that requires the further qualification that overall atmospheric moisture loading is enhanced by rising global temperatures — so comparatively less heavy rainfall is a relative term here.

At this time, NOAA favors a transition to La Nina forecast stating:

“A transition to ENSO-neutral is likely during late Northern Hemisphere spring or early summer 2016, with a possible transition to La Nina conditions by fall.”

However, it’s worth re-iterating that the CFSv2 model forecasts have been quite accurate in predicting the path of the current record El Nino to date.

Links:

NOAA/CPC

NASA GISS

Hothouse Mass Casualty Event Strike Eqypt

Southern Hemisphere’s Strongest Storm on Record

Punishing Four Season Storm Grips US

A Monster Arctic Melt Season May Have Already Begun

Deep Ocean Warming is Coming Back to Haunt Us

Warm Arctic Storm to Unfreeze the North Pole

More Signs of Gulf Stream Slowdown as Floods Devastate Cumbria England

Deconstruction of Asia’s Wild Weather

Hat tip to Caroline

 

Sea Ice Death Spiral Continues — Start of 2016 Sees Arctic Ocean Ice Hitting New Record Lows

In January, Arctic sea ice extent hit a new record average low for the month. Meanwhile, during the first days of February, both Arctic sea ice extent and area hit new daily record lows even as global sea ice area also entered the second lowest range ever recorded. And so it seems that the sea ice death spiral of a record warm world continues.

January lowest sea ice on record

(According to the National Snow and Ice Data Center, Arctic sea ice extent averages were the lowest on record for the month of January since at least 1979. The new low beats out 2011, continuing an ongoing decadal January decline of about 420,000 square kilometers every ten years. Image souce: NSIDC.)

But before we go more into the new spate of record low Arctic and global sea ice measures, it’s important to consider the context — our world has not seen the current level of heat forcing from greenhouse gasses (CO2 + methane + NOx + other greenhouse gasses) in the atmosphere since about 15 million years ago. It’s an unprecedented amount of hothouse potential that is having equally unprecedented results.

Unprecedented Volume of Heat Trapping Gasses Drives Raging Atmospheric and Ocean Warming

About 50 billion tons of CO2 equivalent from all those greenhouse gasses hit the Earth’s atmosphere each year these days. In vast part driven by industrial fossil fuel burning and extraction, this unconscionable, monstrous, and difficult-to-imagine accumulation of heat-trapping vapors is pushing the world to warm up at an unprecedented rate. A pace that is now at least 20 times faster than the widespread warming that occurred at the end of the last ice age.

Temperatures above 80 North

(It’s likely been a record warm start of the year for the Arctic above the 80 degree North Latitude Line. Temperatures in that high Arctic region have tended well outside the 2 standard deviation range and have hit above the record line on numerous occasions. Image source: NSIDC.)

Back then, it took about 2,500 years for the Earth’s atmosphere to heat by 1 degree Celsius for a total of a 4 C temperature increase over 10,000 years. By just this past year, in 2015, fossil fuel burning had managed to do more in 135 years than what an Earth System rising up out of an ice age did in all of two and one half millenia. For 2015 hit a new record high of about 1.1 C above 1880s averages in all the major global temperature monitors (NASA, NOAA, JMA, UK MET Office). It’s amazing, crazy, terrifying to think about. The end of the last glacial period was a great upheaval that violently re-shaped our world. And fossil fuel industry is running a similar, if much more dangerous, geological process in fast forward by pumping out heat trapping gasses at a rate at least six times faster than anything seen in all of Earth’s history.

Yet as amazing as the current rate of atmospheric warming is, it’s just the thin lens through which a vast amount of heat is transferring into the world’s ocean systems. In fact, according to Peter Gleckler, an oceanographer at the Lawrence Livermore National Laboratory “Ninety, perhaps 95 percent of the accumulated heat is in the oceans.”

Arctic Sea Ice Concentration January

(What was possibly the warmest January on record for the Arctic contributed to major sea ice losses in almost all of the major ice formation basins. Image source: NSIDC.)

And all that extra heat doesn’t just sit there. It goes to work transforming water to water vapor — shoving atmospheric moisture content 7 percent higher for each degree Celsius of warming even as it amps up the rate at which water evaporates from the Earth’s surface or falls down in the form of precipitation. Perhaps still more ominously, this heat goes to work melting the great white ice coverings it comes into contact with at the shoreline and upon the ocean surface.

Arctic Sea Ice Hits New Record Lows For January Through Early February

For 2016, that heat has led to new record lows in Arctic sea ice extent and area even as it has pushed global sea ice coverage within striking distance of a scant range never before seen in the whole of the modern era. New record daily lows for sea ice extent — now an almost annual occurrence for at least some time during the calendar year — are now also being breached.

Arctic Sea ice area new record lows

(Arctic sea ice area explores new record low territory on January 29 through 31 of 2016. Image source: Cryosphere Today.)

In the major monitors, Arctic sea ice extent hit a new record low average for the month of January, 2016. This average included a number of record daily lows early in the month even as the entire monitor held within 1st to 3rd lowest on record for each day throughout January. Record daily lows were again breached in the NSIDC measure on January 29th. A streak that continued on through February 1st with totals hitting 13.911 million square kilometers for the day. That’s 119,000 square kilometers below the previous record daily low for February 1 set in 2011 at 14.030 million square kilometers or a region of ice lost below the previous minimum extent slightly larger than the State of Virginia.

Arctic sea ice area as recorded by Cryosphere Today (see graphic above) followed a similar record low range through the end of January. By January 31st, the most recent date in the measure, Arctic sea ice area had hit 12.27 million square kilometers or about 61,000 square kilometers below the previous record daily low for sea ice area set during 2006.

globalice

(A very warm Arctic during January of 2016 likely contributed to shoving the global sea ice area measure into striking distance of new record lows by early February. Image source: Pogoda i Klimat. Data Source: Cryosphere Today.)

Also disturbing is the fact that global sea ice area — which has shown consistent losses over time — has also now come within striking distance of new record lows. The Cryosphere Today monitor now shows global sea ice area in the range of 14.5 million square kilometers or just above previous record lows set during 2006 for this time of year.

Conditions In Context — Amazing Sea Surface Temperature Anomalies, Major Winter Warm-ups Hit Sea Ice Hard

Arctic sea ice area negative anomaly is now in the range of -1.23 million square kilometers. With Antarctic sea ice at around 200,000 square kilometers below average, it’s pretty clear that the bulk of current global sea ice losses are now ongoing in the Arctic.

Warm ocean waters, especially in the Barents Sea and the Greenland Strait are likely major contributors to record low sea ice extents during recent weeks. These sea surface temperatures now show between 1 and an amazing 8 C above average reading in the NOAA sea surface temperature anomaly map below.

NOAA Sea surface temperature anomalies

(Sea surface temperatures are in the range of 4-8 degrees Celsius or 7-14 degrees Fahrenheit above average near sections of sea ice in the Northern Barents Sea. These very warm sea surfaces continue to suppress refreeze and provide melt pressure on into early February. Image source: NOAA.)

Such amazingly warm waters likely helped contribute to major atmospheric warming events in the high north over the past two months including one above freezing event at the North Pole during late December and another near freezing event for the same region during late January, likely added to the overall melt pressure. The very warm water in the Barents likely helped to enable the observed warm air slots that formed north of Svalbard and on toward the North Pole on numerous occasions.

Over the next seven days, Arctic air temperatures are expected to range about 1 C above average — as opposed to the 2-3 C above average range seen during the past month. This slight cooling may allow for a more rapid freezing of some regions including the Sea of Okhotsk. But overall warm waters and airs along the sea ice edge in the Bering and Barents should continue to suppress major ice formation there. By the second week of February, risk increases that high amplitude Jet Stream waves will deliver another burst of warm air to the far Northern Latitudes, potentially continuing the trend of extreme above average atmospheric temperatures in the region of the Arctic Ocean during 2016.

 

 

Links:

NSIDC

NASA GISS

Arctic Sea Ice Graphs

The Arctic Sea Ice Blog

This is Where 90 Percent of Global Warming is Going

CO2 Rising Ten Times Faster Than PETM

NOAA

Cryosphere Today

Pogoda i Klimat

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