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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.

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Siberian Heatwave Wrecks Sea Ice as Greenland High Settles In

We’ve never seen Arctic sea ice extents that are as low as they are now in early June. And with Arctic heatwaves, warm winds, warm storms, and a Greenland High all settling in, something had better change soon or otherwise the ice cap over the northern Polar Ocean is basically screwed.

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On the shores of the Arctic Ocean’s East Siberian Sea (ESS), near the town of Logashinko, temperatures today are expected to rise to near 80 degrees Fahrenheit. Readings that are about 40 to 50 degrees (F) above normal for this near-polar region during this time of year.

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(Welcome to increasingly ludicrous climates. Temperatures near 80 F at Logashinko, Russia are at least 40 degrees F above average for this time of year. A place well north of the Arctic Circle, but whose temperatures are predicted today to match those of St. Martin Island in the tropics. Image source: Earth Nullschool.)

We would have never expected temperatures to have risen so high near typically frozen Logashinko during early June sans the heating effect of atmospheric CO2 levels that have this year peaked near 407.5 parts per million. The highest levels seen on Earth in about 15 million years. These scorching polar temperatures were driven north by a powerful high amplitude ridge in the Jet Stream that has dominated Eastern Russia for much of 2016 Spring. This expansive ridge enabled extreme wildfires popping up all over the region even as it today drives 80 degree weather all the way to Arctic Ocean shores — enforcing a regime of rapid sea ice melt over the East Siberian Sea.

ESS, Laptev Get Ripped Up

As the warm winds drive northward across ice-clogged Arctic Ocean waters, temperatures rapidly fall into 35 to 41 degree (F) ranges. And though that may sound cool to the casual observer, for the East Siberian Sea zone during early June, that’s scorching hot — topping out at more than 10 degrees above average for some areas. A pretty extreme variation for late Spring when temperatures over the Arctic Ocean only typically depart from average by about 3 or 4 degrees at most.

East Siberian Sea Melting

(The Laptev and East Siberian Sea Ice is getting ripped up by extreme Arctic warmth. The blue tint to ice in the above image indicates melt ponds, while dark blue indicates open water. Zooming in closer reveals the brown flush of warm waters issuing from heated Siberian rivers. Image source: LANCE MODIS.)

All across this Arctic Ocean region, melt ponds and widening polynyas now abound in the ridiculously warm airs. In the satellite shot above, the tell-tale bluish tint of the ice reveals a plethora of these ponds expanding northward through the ESS and on toward the pole. A flush of hot water running into the Arctic Ocean from East Siberia’s rivers is melting the near shore ice. And a giant 80 mile wide gap of open water has now been torn into the ice of the Laptev Sea.

Record Extent Lows Continue to Worsen

The sudden Arctic heatwave and rapid related melt involvement of the ESS and Laptev is just the most recent melt spike in a polar ocean that sees ice extent levels hitting new record lows with each passing day. As of June 2nd, the expanse of Arctic Sea ice only measured 10.37 million square kilometers. This is about 430,000 square kilometers below the previous daily record low set just last year and fully ten days ahead of the record sea ice melt year of 2012.

Arctic sea ice extent new record lows

(Arctic sea ice extent record lows continue for this time of year and threaten to plunge deeply below the 2012 line in coming days. Image source: JAXA.)

A coverage of sea ice that is now 42 days and 2.1 million square kilometers of sea ice loss ahead of an average melt year during the 1980s.

Here Comes the Greenland High

Extreme heat building into the Siberian side of the Arctic and record low sea ice extent measures are today being joined by yet another disturbing Arctic feature. For as of yesterday, a strong ridge of high pressure began to form over Greenland, the Canadian Archipelago and Iceland.

Greenland highs tend to increase temperatures over the enormous glaciers of that frozen island even as the clockwise circulation pattern of an anticyclone tends to shove sea ice out into the Barents and North Atlantic. The dominance of a Greenland High during both 2012 and 2007 is thought to have heavily influenced record end season sea ice melts during those years as well as the extreme Greenland surface melt spike during 2012.

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(A high pressure ridge emerging over Greenland, Iceland and the Canadian Archipelago today is expected to strengthen this week — generating a high pressure gradient between warm storms developing over the Arctic Ocean and winds that threaten to increase the rate of ice transport out of the High Arctic and into regions of warmer water. Image source: Earth Nullschool.)

This week’s predicted ridge formation is not expected to bring with it a severe surface melt of Greenland. However, the clockwise winds driving sea ice transport may serve as yet one more heavy blow to the already greatly weakened ocean ice. Pressures later this week are expected to rise to 1040 mb over Greenland. And strong winds running between powerful warm storms expected to form in the Kara and Central Arctic are predicted to rise to near gale force north of Greenland — generating a risk of a very vigorous ice loss from the near polar zone as floes are driven into warm Barents and North Atlantic waters.

In context, the combined severe record sea ice lows and emerging weather conditions represent a seriously bad state for Arctic sea ice. One with a high risk of continued further extreme losses and new daily record lows for at least the next seven days.

Links:

Earth Nullschool

LANCE MODIS

JAXA

Arctic Sea Ice Graphs

The Arctic Ice Blog

Hat tip to Greg

Hat tip to Cate

Hat tip to DT Lange

Gale After Gale After Gale Dumped Two and a Half Feet of Rain Upon Scotland and Wales This Winter

Reports from the UK Met Office are in. And we can say now with confidence that the UK have never seen weather like what they experienced this Winter. It looks like a storm track super-charged by climate change really socked it to the region this year. That we’ve just passed a winter worse than the then record years of 2013 and 2014 — only two years on.

A Stormy New Climate State for the North Atlantic

For the UK and for North Atlantic weather stability in general, the sea surface temperature anomaly signature in the graphic below is bad news. The cool pool just south of Greenland (indicated by the swatch of pale blue) is a new climate feature. One that appears to be related to glacial ice melt outflow from Greenland.

North Atlantic Sea Surface Temperatures

(10 degree Celsius above average sea surface temperatures off North America in today’s ensemble sea surface temperature model graphic are just insanely warm. Ocean surface anomalies used to rarely exceed 2 degrees Celsius warmer than average. These spikes off North America are an indication that the Gulf Stream is backing up and that overturning circulation off Greenland is slowing down. Image source: RTG-SST/NCEP /US National Weather Service/Earth Nullschool.)

Such melt outflow tends to slightly freshen sea surface waters. Freshening waters keep more heat locked into the ocean’s depths. They tend to cool the surface waters. And they slow down an ocean overturning circulation that, in the North Atlantic, drives the flow of the Gulf Stream.

A slowing Gulf Stream delivers less heat to this zone even as it piles more heat up off the North American Coast. As a result, a warm west, cool east dipole tends to develop. In the cool region south of Greenland, unusually strong storms have developed more and more frequently — with a dramatic impact on UK weather. The storms feed on this temperature differential even as they have gorged on heat and moisture streaming northward in a meridional flow over Western Europe. The results this year were nothing short of record-shattering.

Hottest and Wettest

For England and Wales, with temperatures ranging about 2 degrees Celsius above average for December, January and February, 2015-2016 probably beat out 2007 and 1989 as the hottest Winter on record. Meanwhile, Wales and Scotland saw the most rainfall ever recorded — with totals for both regions hitting around 756 millimeters or about two and one half feet. That’s even more rainfall than the previous record stormy Winter of 2013 and 2014.

Yet one more Gale

(Yet one more gale sets up to hammer Ireland, the UK and Scotland by Thursday. Four months of ongoing stormy conditions appears set to continue through to at least mid-March. Image source: NOAA’s Ocean Prediction Center.)

These heavy rains set off severe floods and damaged homes, roads, and bridges throughout the UK with the worst damage focusing in on regions to the North. One heavy precipitation hot spot — Argyll — saw an extraordinary 1035 mm or 3.5 feet of rainfall over the three month period. The Met Office is quick to point out that though December, January and February were the wettest on record since 1910, heavy rainfall events began in November — resulting in what amounts to a relentless four month pounding as storm followed storm and flood followed flood.

And, it appears, this persistent and ongoing storm pattern has not yet changed. For the North Atlantic remains riled — setting up to hurl a new gale-force low at Ireland and the UK this week. With the weather pattern essentially stuck in stormy since November, folks from these regions have got to be asking — when’s it going to end? As storms continue to fire off in the dipole zone above, it appears it will likely last until at least mid-March.

Links:

The UK Met Office

NOAA’s Ocean Prediction Center

World Ocean Heartbeat Fading

RTG-SST/NCEP /US National Weather Service/Earth Nullschool

Winter of 2015/2016 Wettest on Record for Scotland

Mystery Deepens Around Greenland Cold Spot

Hat tip to Colorado Bob

Hat tip to TodaysGuestIs

Hat tip to Dan Combs

 

 

 

 

 

 

June Snow Melt Brings July Arctic Sea Ice Drop-off

It’s a pretty well established theory. If snow over the Northern Hemisphere land and sea ice masses substantially melts during May and June, it can tend to set up a general weather pattern that is conducive to large-scale reductions of the Arctic sea ice come July, August and September.

Arctic Sea Ice in ragged condition during mid July

(Arctic sea ice in very ragged condition by July 19, 2015. A situation born of a continuous Greenland and Central Arctic high pressure ridge setting up warm air build-ups and a sea ice-flushing dipole weather pattern. Image source: LANCE-MODIS.)

Arctic High Pressure, Heat, Collapsing the Sea Ice

And, during June, we saw just this kind of trend emerge. Arctic heatwaves over both the Continental land masses and the Arctic sea ice resulted in a rapid melting of snow cover. Heatwaves fed by massive bulges in the Northern Hemisphere Jet Stream, particularly along the now-famous Ridiculously Resilient Ridge over what is today an amazing (horrific) hot zone of Northeastern Pacific surface waters. El Nino and Positive PDO played their role too, kicking up the hot zones and the ridge to ever greater intensity. An atmospheric and ocean synergy in a 1 C hotter than 1880s context that kept hurling more and more heat into the Arctic environs. Melting more snow and setting the stage for a potential sea ice massacre to come.

By early July there were indications that just such an event may be on the way. A ‘heat dome’ type high pressure system had become well established over the Greenland side of the High Arctic. And for the past three weeks now, this high has remained entrenched. A persistent weather pattern that has allowed more sunlight to hit the sea ice during periods of peak insolation, a pattern that compacts sea ice in the Central Arctic, a pattern that draws storms into the Siberian side of the Arctic to chew away at the ice edge, and a pattern, that overall, drives the ice inexorably toward its Atlantic Ocean flush valve in the Fram Strait.

Arctic Heat

(Hot to record hot conditions have remained in place over the Arctic Ocean throughout July. Image source: NSIDC)

All this extra heat, transport, compaction and storms chewing away at the sea ice edge has finally started to take a very serious toll. As of today, sea ice extent measures had dropped from 7th to 10th lowest on record to 6th to 7th lowest. Area has remained at 4th to 5th lowest on record for the date. Meanwhile volume in the DMI measure has dropped to 2nd lowest on record.

Most charts now are starting to show a steep ‘cliff’ type rate of decline indicative of rapid sea ice collapse. This is particularly true in NSIDC’s Charctic and Cryosphere Today’s sea ice graphs which now show both extent and area lines plunging at rates that will rapidly cross new thresholds if they continue over the coming days.

Sea Ice Concentration in a Rough State

But perhaps most disturbing of all are the indicators that are now showing up in nearly all of the visual concentration monitors. Uni Bremen sea ice concentration continues to look like a massacre on the Pacific side. NSIDC doesn’t appear to be much better. But Cryosphere Today takes the cake for an overall display of sea ice weakness that, on the 19th (updated as the CT measure used earlier ended up being a bit off), looked nearly as bad as on the same day during the record melt year of 2012:

2012 to 2015 Comparison

(Comparison of July 19, 2015 and July 19, 2012 shows 2015 looking nearly as bad as 2012 in the concentration measure. Image source: Cryosphere Today.)

Comparing the left frame image with the MODIS satellite shot at the top of this post, we find confirmation of an overall, very weak sea ice state. Concentration throughout the Arctic appears low. This is especially true on the Beaufort, Chukchi and East Siberian Sea side (see MODIS shot at bottom of post). But extensive weakness and low concentration appears to pervade the entire ice mass. Zooming in on the sea ice surface, we find that some of this low concentration is possible to confirm. The entire Arctic is now full of broken floes, polynya and melt ponds.

Though it is also possible that this extensive melt ponding (also a feature that weakens sea ice) may have kicked the Crysosphere Today concentration sensor a bit into the extreme scale (corrected during the past 24 hours), the 2012-to-2015 comparison above is still apples to apples. And what’s a bit disturbing about this comparison is the fact that much of the concentration in red (55 to 70 percent) in the 2012 measure completely melted out at the ocean surface by mid September of that year. More notably, perhaps, is the fact that the Cryosphere Today concentration measure is, at least in part, confirmed by the US Navy ARCc Concentration model which has now begun to pick up some of the earlier predicted rapid melt in the observational ensemble:

US Navy Concentration

US Navy Concentration Forecast

(Sea ice massacre starting to show up in the US Navy ARCc model daily observations [top frame] and continues to be predicted in the 30 day history and 7 day forecast [bottom frame]. Image source: US Navy.)

Above, we see very low sea ice concentration practically anywhere outside the 80 degree North Latitude line. Most notably, concentration is very thin and rapidly weakening in the Beaufort, Chukchi, East Siberian, and Laptev Seas. And the seven day forecast shows very rapid melt throughout all these regions with the low concentration bulge beginning to invade north of the 80 degree line on the Laptev and ESS side in particularly troubling fashion.

Forecast — Continued Rapid Melt, Some Records May be Threatened

So the question, going forward, is — what next? And it appears that the sea ice is being prepped for continued rapid to accelerating melt over at least the next 7-10 days. Seven day forecasts show the ridge remaining on the Greenland side of the Arctic throughout the period. A position that will continue the current melt, transport and ice weakening regime. Longer range, ten day, ECMWF forecasts find the high shifting more toward a strong ‘heat dome’ located in the Central Arctic with a somewhat weaker high remaining over Greenland — a minor variation of the current ice-weakening state that may slow down ice export but leave compaction, melt ponding, heat build-up, and ice edge weakening due to storms in tact.

Very weak sea ice

(Sea ice throughout the Beaufort, Chukchi, ESS and Laptev is very weak. Can it survive another 10 days of the Greenland/Central Arctic heat dome? Image source: LANCE-MODIS.)

Due to this weather forecast and due to some observations beginning to come in line with ARCc model runs, we cannot rule out a very rapid melt and recession of sea ice along a broad arc running all the way from the Canadian side to East-Central Siberia. The sea ice is visibly very weak there. Perhaps the weakest we’ve ever seen it for this time of year. Ice that will continue to be pulled poleward by the highs that are forecast to remain in place. Ice that will run into weakened, melt pond invaded ice — a paltry respite for its retreat. And ice that will continue to be harried by edge storms and an influx of much hotter than normal air and water from the Pacific Ocean side. It’s a rapid melt risk that calls into effect the potential that some old sea ice area, extent, and volume records may be challenged or broken — probably not 2012’s all time low marks, but more possibly 2011 or 2007.

It’s, overall, a very tenuous situation for sea ice, one that is continuing to be fed by a growing El Nino and still firmly entrenched RRR to the south. So the evolution of sea ice melt over the next few weeks will likely be a critical game-maker for the state of Arctic Sea ice melt and the overall story of Arctic Sea Ice decline in this sad age of human-forced climate change.

UPDATED JULY 21, 2015

Links:

LANCE-MODIS

NSIDC

US Navy

Cryosphere Today

Uni Bremen

June Arctic Heatwave Takes Down Northern Hemisphere Snow Cover

Halfway to 2 C

Arctic Heatwave Pummels Sea Ice in Early July

See Beaufort and Northwest Passage Melt Progress Over at The Arctic Sea Ice Blog

(Please support public, non-special interest based science like the work conducted by the national snow and sea ice monitors, NOAA and NASA. Without their ongoing work, this analysis and commentary would not be possible.)

Accelerating Global Warming? NASA Shows February of 2015 was Second Hottest on Record

The Earth started out 2015 very hot. A record hot range that some researchers are now saying may be the beginning of a period of accelerated global warming.

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For the global temperature measure, February of 2015 was another extraordinarily warm month. One more hot month in an unbroken chain stretching all the way back to the mid 1980s. The second hottest February in the whole of the NASA record ever since temperature monitoring began in 1880.

In total, NASA GISS shows February of 2015 topping out as the warmest February of the new millennium at 0.79 degrees Celsius above the 20th Century average. A reading 1.06 C above temperatures measured during 1880. Only February of 1998 was hotter (Of all of the super El Nino year of 1998, only February and June still hold records as hottest months in the NASA measure).

But perhaps most importantly, the average of 2015’s first two months is 0.77 C above the 20th Century. This is just behind 2007 (by just 0.02 C) as the hottest two-month start of any year during the past 135, and likely hotter than at any time during the Holocene and possibly in the past 120,000 years altogether.

Temperature Map February NASA

(Global temperature anomaly map. Image source: NASA.)

Global temperature anomaly analysis by NASA shows extraordinary warmth for much of the Northern Hemisphere. In particular, most of the land mass of Asia experienced far above average readings. Temperatures in this zone measured as high as 8.4 degrees Celsius above average for the entire month — yet one more extraordinary period of departure for a rapidly warming region.

The North American West Coast through to Alaska also showed much warmer than normal readings. A pattern coincident with both a vast pool of warm water in the Northeastern Pacific and a ridiculously resilient ridge of high pressure (and coincident high amplitude wave in the Jet Stream) that has formed for seasonal periods over the region since the winter of 2012-2013.

Abnormal warmth was also pervasive through the tropics, the Arctic, Africa, Australia, sections of East and West Antarctica, and over most Oceanic zones. The only region experiencing colder than normal readings was the Eastern Half of North America. An area in the downward sloping trough of the prevalent Rossby Wave and associated hot-cold dipole pattern that has been so common for North America during recent winters.

Zonal Anomalies Feb 2015

(Temperature anomaly by Latitudinal Zone for February of 2015. Image source: NASA.)

NASA’s zonal anomalies measure shows very strong polar heat amplification, which is a tell-tale of the human greenhouse gas heat forcing, at the Arctic Circle line (66 North Latitude) and continuing on northward. Zonal anomalies peaked at around the 66 degrees North Latitude line in the range of 2.8 C above average for the entire month. Anomalies declined poleward but still maintained 1.5 to 2.5 C above average ratings.

Though somewhat cooler than the Northern Polar Region, the rest of the global also showed above average temperatures in almost all zones. 30-60 North showed readings ranging from 0.5 to 2.5 C above average, the tropics maintained about a +0.6 C above average range, 30-60 South ranged between 0 and 0.6 C above average with a dip in the heat sink and high wind region of the Southern Ocean. The Southern Polar Region showed the only zonal below average reading with -0.2 C between 85 and 90 South, but the entire region of 60-90 South ranged about 0.15 C hotter than average.

Conditions in Context

The main features of the current globally hot February are a weak El Nino in the Central Pacific (declared by NOAA in early March), a strong positive PDO pattern of very warm sea surface temperatures throughout the Pacific and an extreme polar amplification in the region of 60-90 North Latitude.

According to IPCC forecasts and Pacific Ocean warming impact studies, both the El Nino, which has tended to shift more toward the Central Pacific, and the amazing polar amplification are indications of what was expected in a world seeing a rapid accumulation of greenhouse gasses through the mechanism of human fossil fuel emission. The North American Rossby Wave pattern combined with extremely warm temperatures in the West and cold, stormy and snowy conditions in the East, was also predicted as a potential upshot of warmer than normal readings at the pole reducing temperature differentials from North to South and encouraging weakness and waviness in the Jet Stream (Francis). PDO intensification, contributing to a warm water pool off the North American West Coast and coincident mid Pacific El Nino may also have a teleconnection-type (Where large weather patterns reinforce and enhance the formation of other large weather patterns that may be hundreds or thousands of miles removed from the first. Some have poetically referred to teleconnection as an atmospheric dance.) influence with the ridging pattern in the west and the related troughing pattern in the east.

In global climate models, cool pools of water near Greenland and West Antarctica are also implicated in potential trough/Rossby Wave type patterns (severe frontal storms) which may also be influencing the extreme weather seen in the Northeastern US during February. These pools are associated with glacial melt and coincident fresh water outflow. In the North Atlantic, this has implications for global thermohaline circulation. A strong thermohaline circulation is essential for ocean mixing and related ocean health.

Overall, the global temperature disposition, extreme temperature anomaly, and related strange weather patterns are anything but a normal. They are instead indicative of the kinds of extraordinary climates and extreme weather both computer models and researchers have predicted as a direct result of human-caused warming.

Entering a Rapidly Warming World

entering a rapidly warming world

(Even with a rapid draw down in human emissions to RCP 4.5 levels, computer model essays show 40 year average rates of warming will likely accelerate over the next few decades. Image source: Near-Term Acceleration in the Rate of Temperature Change.)

To this point, it appears that some climate models are in agreement that the period of the next few decades are likely to see an accelerated warming trend. Decadal rates of warming, during this time, are expected to accelerate to between 0.2 and 0.25 C per ten years, even if human greenhouse gas emissions are rapidly drawn down. The result would be about 1.4 to 1.6 C worth of warming above 1880s levels by or before 2040. Without a rapid draw-down, and a continuation on the current catastrophic path of fossil fuel burning, recent model essays from Dr. Michael Mann indicate that humans could exceed the 2 C warming threshold by the mid 2030s.

Links:

Near-Term Acceleration in the Rate of Temperature Change

GISS Surface Temperature Analysis

Paleoclimate Implications For Human-Made Climate Change

Warming Arctic May be Causing Heatwaves Elsewhere in the World

The California Weather Blog

Increasing Intensity of El Nino in the Central Equatorial Pacific

Evidence Linking Arctic Amplification to Extreme Weather in the Mid-Latitudes

Greenland Melt — Exponential?

Far Worse than Being Beaten With a Hockey Stick

Earth Entering a New Period of Rapid Temperature Change

Hat tip to Bassman

Mangled Jet Stream + Global Warming + Hot Atlantic Water = Boston Buried Under 8 Feet of Snow

If you deny that warmer ocean temps -> greater snowfall w/ coastal winter storms, you are not a climate denier. You are a physics denier. — from the Twitter feed of Dr Michael E. Mann, Climate Scientist

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Boston just experienced its snowiest month on record and, yes, it really is climate change, stupid. In essence, as Michael Mann notes above, it’s a matter of oceanic and atmospheric physics.

Consider the fact that the ocean surface is warming at an unprecedented rate. Consider also the fact that this observed warming is resulting in a number of powerful south to north flows of air over ocean regions and toward the polar zone.

Over the past month, these powerful warm air flows pushed strongly into both Alaska and Svalbard — causing 20-30 C above average temperatures in regions of the Arctic along the 70 to 80 degree north latitude lines. For Alaska, the warmth was so prevalent and intense that it forced the Iditerod sled dog race to be moved 300 miles north for want of snow and ice. On this past Sunday night in Svalbard, just above the 80 degree north latitude line, temperatures were a balmy 1.2 degrees Celsius. An extraordinary above freezing reading in a land where temperatures during this time of year are typically 20 to 30 degrees Celsius below that mark.

image

(Anomalous above freezing temperatures in the land of winter dark and chill. Also note the very powerful south to north air flows originating from the 30 degree north latitude line and terminating in the Arctic near 70 to 80 north. These flows exist in both the Pacific and the Atlantic — hugging the coastal zone and flowing strongly northward along a reoriented storm track. Image source: Earth Nullschool. Data source: Global Forecast System Model.)

All this warm air moving north must have an impact. And that impact is to leave Greenland and the eastern North American Continent as the remaining refuge for cold Arctic air that would typically amass over a rather thick pack of sea ice. But that sanctuary for cold is increasingly frail and unstable. For the ice is thinner and itself rests upon waters that are warming. So the cold instead moves to land and to land ice — both bodies with physical properties better able to keep cold during the long winter dark.

So the cold flees its previous habitat in the far north near the pole and instead dives about 1,500 miles south over Greenland, Eastern Canada and the US. In the upper atmosphere, this pattern is reflected by a huge trough in the Jet Stream. One that has been repeatedly identified by the crackerjack research of Dr. Jennifer Francis.

image

(Very high amplitude Jet Stream wave pattern with strong ridge in the west, very deep trough digging through Eastern Canada and the Eastern US, an a return to the strong ridge pattern over the North Atlantic. Image source: Earth Nullschool. Data source: Global Forecast System Model.)

Such a powerful hot-cold dipole in the atmosphere results in extraordinary atmospheric instability. The deep trough alone would be enough to send storm after storm hurtling toward the Northeast US. Storms born of a fury of Arctic cold coming into collision with oceanic moisture from the Gulf of Mexico and the Atlantic.

It is a pattern that has been fixed in place for a month running. One that has delivered storm after powerful storm to the US northeast along a screaming storm track. And one that has slammed these storms into an unprecedented wall of warmth and moisture.

For not only have warm air flows invaded the Arctic resulting in a highly anomalous displacement of cold air southward for an extended period of time. But ocean warmth in a region of the Atlantic just off Boston has provided extraordinary fuel for these storms once they arrive.

For we have observed sea surface temperatures just off Boston in the range of 8-11 C above average for most of the months of January and February:

image

(Sea surface temperature anomaly map by Earth Nullschool. Note the highlighted region shows an extreme temperature departure of 11.1 degrees Celsius above average. Data Source: Global Forecast Systems Model.)

For reference, a sea surface temperature anomaly of 2 C or higher is considered to be a rather strong departure. The 11.1 C anomaly in the above image is, for lack of a better term, simply off the charts. In rough translation, this amounts to surface waters in the range of 65 to 70 degrees Fahrenheit only about 200 miles or so off the Massachusetts coastline. A coastline regularly seeing temperatures in the range of 0-28 degrees F. The result is a 40-70 degree temperature departure over a very short distance. By itself, this extreme temperature differential would be an amazing storm generator. But the differential alone only tells half the story.

The other half is a powerful explosion of moisture off this much warmer than normal water. A massive mushrooming of moisture just off the coast. And when this very heavy bank of moisture collides directly with displaced onrush of cold and dry air, the amount of snow that is squeezed out can be staggering.

Record-breaking staggering. 8 feet for Boston in one month staggering.

As Michael Mann so saliently noted, you’d have to be a physics denier to not understand the role of ocean warming in either the warm air invasion of the Arctic in the Oceanic zones, the related displacement of cold air over the eastern half of the North American continent, or the fueling of extraordinarily powerful winter storms along the Northeastern Coast of the US.

And to this point, I leave you with the equally salient thoughts of Bill Nye from his twitter feed:

Bill Nye

“Would this guy get fired, if mentioned, just mentioned a possible connection, to ?” — Bill Nye.

Links:

Michael Mann and Bill Nye Want You to Know Boston’s Epic Snowfall is Tied to Global Warming

Global Forecast Systems Model

Earth Nullschool

Bill Nye’s Twitter feed

Dr Michael E. Mann’s Twitter feed

Scientific hat-tip to Dr. Jennifer Francis

Hat tip to Eric Thurston

 

 

 

 

 

Winter of 2013-2014 Sees Most Extreme Dipole on Record: How a Strong Emerging El Nino Conspired With Climate Change to Ignite Record Drought in California and Collapse the Polar Vortex

Dipole. It’s a word often used among meteorologists and climate scientists. But what does it mean?

In weather terms we can simply think of it as this: one side hot, one side cold. So, as a basic principle, it’s pretty direct. But in a world where extremes between hot and cold are becoming more intense, in North America which has just experienced its most extreme dipole anomaly since record keeping began in 1960, it’s also something that’s important to understand as it relates to ongoing human-caused climate change.

For a recent blockbuster scientific paper by Dr. Simon Wang and associates and published in Geophysical Research Letters has now linked this extreme temperature differential, related polar vortex collapse events, and the California drought with both ongoing physical changes to the Earth System due to human caused climate change and to the first rumblings of a monster El Nino in the Pacific.

Envisioning a Dipole Pushed into An Extreme Form by Climate Change

But to understand how an excessively extreme dipole relates to the historic events of the winter of 2013-2014, it helps to open up one’s imagination. It helps to describe the ground-breaking information provided by Dr. Wang’s new paper in descriptive terms. It helps to, at first, envision a wave. Then to imagine the up-slope of the wave forming a hot, red shape. Now imagine the down-slope forming a cold, blue shape. Now think of this wave growing more intense, extending further in both its up-slope and in its down-slope. Growing hotter on the up-slope side and comparatively colder on the down-slope side.

Polar Vortex Collapse January 19

(GFS Model summary of Polar Vortex Collapse event on January 19, 2014 shows 850 mb temperatures over the Eastern US colder than the same temperatures over parts of Greenland and the Arctic Ocean. 850 mb temperatures over St. Augustine, FL are the same as 850 mb temperatures over central Greenland. Anomalies on the hot side of the dipole in the Arctic hit +40 degrees Fahrenheit in some places.  Anomalies on the cold side of the dipole hit more than -35 degrees F in some places. Note the twin, dense high pressure systems sitting sentinel just off the California Coast and deflecting storms north into Alaska. Image source: NOAA/GFS.)

Having established the wave form and related temperature extremes, lay the shape over North America and adjacent Pacific Ocean. The up-slope covers the Eastern Pacific, Alaska, a section of the Beaufort Sea in the Arctic, Western Canada and the Western US. The down-slope swings from the eastern side of the Beaufort, on in through Central and Eastern Canada and bisects the US diagonally from the Dakotas to the Gulf Coast east of Texas.

Now let’s envision this wave as a flow of upper level air called the Jet Stream and let’s think about the various atmospheric aspects that feed it. Looking west, we happen upon a very warm pool of water in the Western Pacific east of the Philippines. This warm pool is the source of an El Nino that will likely occur within one years time. A heat pocket given added intensity by both rising atmospheric temperatures and strong winds transferring that added energy into the vast Pacific Ocean. The heat waits, wanting to spread out across the Pacific surface in an energetic return to the air. But, for now, it simmers in its deep pool, providing energy for the powerful dipole we’ve just described.

The heat from this warm pool radiates into the atmosphere creating lift. Further north, a cold pocket is driven south by another strong atmospheric wave pattern over the Asian continent. The cold air pocket runs south over Japan. The hot and the cold difference generates a very strong upper level synoptic (horizontal form weather patterns stretching more than 1,000 kilometers) wind pattern that stretches all the way across the Pacific Ocean.

The winds run southwest to northeast until they encounter the hot bulge of our already described dipole over the Eastern Pacific near the US west coast and Canada. This warm current turned the already rapid winds due north where they rushed up over Alaska and into a sea ice pack far weaker than in decades past. A sea ice sheet gradually thinning, breaking up, and venting heat from a warming Arctic Ocean below. And so these, already strong, winds were not turned back by the now much weaker cold until they had driven far, far into the Arctic Ocean (and it is here that we must give a hat tip to Dr. Jennifer Francis, who finds her predictions regarding sea ice loss and high amplitude Jet Stream waves again validated).

Polar Vortex Ripped in Half

(Upper level wind pattern on January 23, 2014 shows a polar vortex that has essentially been ripped in half by the warm side of the west coast dipole and the high amplitude Jet Stream wave forming over top of it. Image source: University of Washington.)

Now imagine a strong dome of high pressure forming in the wake of this powerful and ongoing wind flow, sheltered and growing ever stronger on the hot side of the dipole. Imagine it blocking the path of storms, even as it concentrated heat and warmth. Imagine California receiving 1/4 or less of its typical winter rainfall as a result. A most recent and extreme insult to years of drought forcing authorities to ration water in many places.

Now return to that strong wind finally being turned south somewhere in the far, far north, in the Beaufort Sea just south of the North Pole. Then imagine these now cold-laden winds rushing south. Running over Hudson Bay and eastern Canada. Roaring over the Great Lakes and carrying with them a cyclone of cold Arctic air that should have remained in the far north. The polar vortex that should have stayed over places like Svalbard but instead collapsed under the warm wind flow and shifted far south to places like Toronto or Chicago or Detroit or Washington DC.

Now at last imagine another synoptic pattern as the Arctic air of the polar vortex encounters the warmth of the Gulf Stream. This pattern is laden with powerful storms that bomb out over the UK again and again, resulting in the stormiest winter for that island nation in over 200 years.

And here we have the dipole of the winter of 2013 and 2014. A west coast that was hot, hotter than usual all the way from California to the far north of Alaska and an East Coast that from Canada to the Gulf Coast became the repository for cold, cold Arctic air that was shoved south as the polar vortex collapsed down the steep face of the one of the largest and longest lasting Jet Stream waves on record.

(Dr. Francis explains how polar amplification results in higher amplitude Jet Stream wave patterns.)

Dipole. One side hot. One side cold. But, in this case, in the case of the winter of 2013-2014, it’s a historic and anomalous dipole. A freak born of the climate change we’ve caused mixing up with the Pacific Ocean heat of a rising El Nino. A record hot, dry winter for the US West that ignites wildfires in winter and forces the government to ration California water resources. A severe dry spell that closes farms and drives US food prices up by 15%. A record cold, stormy winter in the Eastern US and a series of super-intense storms screaming across the North Atlantic to submerge Somerset and rip massive chunks out of a rocky UK coastline.

This clear picture of a climate-change caused event was this week provided through the groundbreaking new research by Dr. Wang and fellows. These top scientists engaged climate models and analyzed past records to find the culprits of the weather extremes we witnessed during this past winter. And what they found was a very high correlation in the models with the extreme dipole over North America and the Arctic, an oncoming El Nino, and climate change driven impacts.

For not only was this year’s dipole the most extreme on record, it was also likely made far more extreme by an emerging Monster El Nino acting in concert with severe global-warming related reductions in Arctic sea ice cover, increases in Pacific Ocean heat and atmospheric moisture content, and related changes to the upper level air flows of the Northern Hemisphere polar Jet Stream.

Links:

Probable Causes of the Abnormal Ridge Accompanying the 2013-2014 California Drought, ENSO Precursor and Anthropogenic Warming Footprint

NOAA/GFS

University of Washington

Read Further Excellent Reporting on the Wang Report Here:

California Drought/Polar Vortex Jet Stream Pattern Linked to Global Warming

Bombshell Study Ties Epic California Drought ‘Frigid East’ To Manmade Climate Change

Large and Growing List of Scientific Studies Linking Human Climate Change to Current Weather Extremes (hat tip to Weather Underground)

Changing the Face of Mother Nature

The Seasonal Atmospheric Response to Projected Sea Ice Loss in the Late 21rst Century

Evidence Linking Arctic Amplification to Extreme Weather in the Mid Latitudes

Influence of Low Arctic Sea Ice Minima on Anomalously Cold Eurasian Winters

Impact of Sea Ice Cover Changes on the Northern Hemisphere Winter Circulation

Impact of Declining Arctic Sea Ice on Winter Snowfall

Large Scale Atmospheric Circulation Changes Associated with the Recent Loss of Arctic Sea Ice

A Link Between Reduced Kara-Barents Sea Ice and Cold Winter Extremes Over Northern Continents

Northern Hemisphere Winter Snow Anomalies

Impact of Projected Future Sea Ice Reduction on Extratropical Storminess and the NAO

Cold Winter Extremes in Northern Continents Linked to Arctic Sea Ice Loss

Precipitation Shifts Over Western North America as a Result of Declining Sea Ice Cover

Disappearing Arctic Sea Ice Reduces Available Water in the American West

Interdecadal Connection Between Arctic Temperature and Summer Precipitation Over the Yangtze River Valley in the CMIP5 Historical Simulations

Potential Impacts of the Arctic on Interannual and Interdecadal Summer Precipitation in China

Influence of Arctic Sea Ice on European Summer Precipitation

On the Relationship Between Winter Sea Ice and Summer Atmospheric Circulation over Eurasia

(Partial list, view the rest here)

 

 

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