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Hellacious Forecasts for Florence

Models are now predicting that Florence will threaten the U.S. East Coast as a major hurricane next week. We are still one week out. And should take any prediction at this time with a grain of salt. However, this is a concerning trend which we should continue to monitor.

Climate change factors discussed RE increasing U.S. East Coast hurricane risks include much warmer than normal sea surface temperatures, lifting of deflecting troughs to the north, and fixed Jet Stream ridge patterns that, when they prevail across the U.S. East, enhance the potential for land-falling storms.

(This is one of five video blogs covering climate change and clean energy posted today on my YouTube Channel. I will post a daily highlight of the feed here. In addition, I will post an in-depth climate change related blog here on a weekly basis as a new format. Warmest regards to all! — R)

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Florence’s Rapid Intensification Surprises

An overview of present tropical cyclone activity over the U.S. and in the North Atlantic to include Gordon, Francis, and a tropical disturbance emerging from Africa. Both National Hurricane Center reports and larger climate change related factors are discussed.

Jebi — Worst Typhoon in 25 Years is Third Major Disaster to Strike Japan

The worst Typhoon in 25 years to strike Japan has forced 2 million to evacuate, injured at least 300, killed 9, and inflicted massive damage on the island nation. Jebi is the third major disaster to impact Japan during the Summer of 2018 — all of which have been influenced by human-caused climate change.

Miserably Hot in Mid-Atlantic? There’s a Reason for That.

High heat index values continued across parts of the Mid Atlantic today with heat index (feels like temperatures) above 100 for many locations. A front, fortunately, is expected to bring some relief by this weekend.

NOAA — 70 Percent Chance of El Nino During NH Winter

An analysis of ENSO trends in which NOAA is indicating a 70 percent chance of El Nino this Winter. El Nino’s interaction with human-caused climate change is also discussed.

Jebi Threatens Japan with 170 Mph Winds

 

The most intense tropical cyclone of 2018 — Jebi — is churning through the Western Pacific. Japan is now in the bull’s eye of the projected path.

Change in the Jet Stream Relieves West, Moves Heat East

A change in the persistent jet stream pattern that enhanced heatwave and fire intensity for the U.S. West is now providing relief. Meanwhile, a building ridge in the east has set the stage for potential record heat.

The Hurricane Models are Starting to Get a Bit Wild

 

Forecast models are indicating that the North Atlantic is much more likely to produce storms as we move into September. In the above video blog, we provide an analysis of the underlying climate and climate change related conditions that may influence the intensity of storms that do form. Particularly those that do approach the United States.

 

“Never Before Experienced” Rains Hammer Japan During Early July

“We’ve never experienced this kind of rain before. This is a situation of extreme danger.” — The Japan Meteorological Agency

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During recent days as much as 25 inches of rain has fallen over parts of Japan shattering previous all time precipitation records for parts of the island nation. The resulting floods have spurred a major emergency response by 54,000 personnel, taken the lives of more than 125 people, and forced more than 2.8 million to evacuate.

(Rising global surface temperatures increase atmospheric water vapor levels — providing liquid fuel that spikes the most powerful rainfall events to even greater extremes.)

On July 3, Typhoon Prapiroon swept over southwestern Japan bringing with it a spate of heavy rains. Over the following days, Prapiroon got caught up in stationary front even as a high pressure system to the east continued to circulate tropical moisture into the region. Beneath that eastern high, sea surface temperatures ranged between 2 and 3.5 degrees Celsius above normal. Meanwhile, warmer than normal ocean surfaces dominated a region east of the Philippines. These large, abnormally warm zones produced excess evaporation which helped to feed even more moisture into the region.

The result was a historic and devastating rain event for Japan. Isolated locations received more than 39 inches (1000 mm) of rain over a three day period. With one hour rainfall exceeding 3 inches in a number of locations. Motoyami received one day rains of 23 inches. With Mount Ontake seeing more than 25 inches over three days.

(Warmer than normal ocean surfaces, as shown in yellow and red in this sea surface temperature anomaly map, helped to fuel Japan’s recent extreme rainfall event. Image source: Earth Nullschool.)

Rising global temperatures increase overall atmospheric moisture loading by approximately 8 percent for each degree Celsius of global temperature increase. Water vapor provides fuel for storms both through enhancing convection and by engorging clouds with moisture. Recent scientific studies have found that climate change can greatly enhance the peak intensity of the most severe storms in this way. And the U.S. National Climate Assessment has identified a historical trend of increasing instances of heavy precipitation.

Pawnee Fire Forces Another State of Emergency for Northern California

Human-forced climate change is driving severe events that local communities are having difficulty recovering from. The primary reason is that the tempo of these events is so high that it allows little time for recovery.

(Another series of intense wildfires, another state of emergency for California.)

This weekend, a large complex of fires erupted in the Lake County region of Northern California. By today, the fires had expanded to cover over 10,500 acres. The rapidly expanding fire has already destroyed more than 22 buildings while forcing 3,000 to flee. Meanwhile, Governor Jerry Brown had declared a state of emergency.

Hot and dry conditions fanned the blazes on Tuesday, increasing concerns that the fires would continue to rapidly spread. Temperatures in Fresno are expected to hit 100 degrees (F) today with readings in Redding likely to hit near the century mark. Meanwhile, a large zone from Death Valley to Vegas to Phoenix is predicted to see temperatures hit 108 to 114 (F) or above.

(Very hot conditions across California are presently elevating fire risk. Already, large blazes have burned numerous buildings and forced hundreds to flee. Image source: National Weather Service.)

These hot, windy conditions will continue to elevate fire hazards across the west — which is bad news for communities beleaguered by the ongoing spate.

During recent years, big swings between heavy precipitation events and hot, dry conditions have fueled larger, more intense wildfires across the U.S. West and particularly in Northern California. Human caused climate change drives these events by adding moisture to the atmosphere which favors heavier storms and by forcing temperatures higher. The result is that vegetation grows and blooms more rapidly during the wetter than normal periods and dries out faster during the hotter than normal periods — generating more dry fuel for wildfires.

 

 

 

Southeast Texas Hammered by 15+ Inches of Rain

It doesn’t take a hurricane or tropical storm to dump massive amounts of rain on southeast Texas these days. Just a wave of tropical moisture from an ocean warmed by human-caused climate change.

(Not a hurricane, but southeast Texas may see 20 inches or more of rain this week.)

Over the past few days, a massive surge of moisture has flowed off the warmer than normal waters of the Gulf of Mexico. This moisture has interacted with a trough dipping down over the Central U.S. to produce prodigious amounts of rainfall. And ever since late Sunday powerful thunderstorms have been firing across the Texas coast.

As of this morning, according to reports from The National Weather Service, between 5 and 15 inches of rainfall had inundated a vast swath stretching from the Texas-Mexico border northward to a Houston area still recovering from Hurricane Harvey’s historic floods. These heavy rains, producing amounts typically seen from a substantial tropical cyclone, have generated major flooding and flash flood warnings across the region. As the waters rise, residents have become justifiably concerned about personal safety and damage to property.

NOAA forecasts indicate that storms expected to continue firing through Thursday, with between 2 and 7 inches of additional rainfall possible. It is worth noting that atmospheric moisture levels over the region are very high. So predicted rainfall totals may be exceeded.

(As of 7 AM, more than 15 inches of rain had fallen over parts of southeast Texas in association with a persistent upper level low and related severe thunderstorms. Heavy rains have continued to fall throughout the day and aren’t expected to abate until at least Thursday. Image source: The National Weather Service.)

During recent years, increased global temperatures have generated more extreme rainfall events for places like southeastern Texas. Warmer ocean surfaces — like those in the heating Gulf of Mexico — evaporate more moisture into the atmosphere. And this moisture generates more fuel for storms — greatly increasing the peak rainfall potential of the most intense storms.

Last year, southeast Texas faced inundation from a number of severe events. A sequence that was capped off by the record-shattering Hurricane Harvey — which tied Katrina as the costliest U.S. storm on record and dumped more than 60 inches of rainfall over parts of the state. Though the present storm event is not likely to reach Harvey levels of extremity, it is a stark reminder that we have entered a new climate and extreme weather regime. One that will continue to worsen so long as we keep burning fossil fuels and forcing global temperatures to rise.

Accelerating Sea Level Rise is Being Driven by Rapidly Increasing Melt From Greenland and Antarctica

From 1993 to the present day, global sea level rise has accelerated by 50 percent. And the primary cause, according to recent research, is that land glaciers such as the massive ice sheets of Greenland and Antarctica are melting far faster than they have in the past.

(Assessment of factors involved in the presently increasing rate of global sea level rise.)

Antarctica, in particular, is melting much more rapidly — with melt rates tripling in just the last ten years.

The primary factors contributing to global sea level rise include thermally expanding oceans and the melting of ice on land. During the decade of 1993 to 2004, the World Meteorological Organization notes that oceans rose by 2.7 mm per year. During this time, land ice sheets amounted to 47 percent of that rise — or about 1.35 mm. The same report found that from 2004 to 2015, oceans rose by around 3.5 mm per year and that land ice contribution had risen to 55 percent (1.93 mm per year). Looking at sea level measurements from AVISO, we find that from March of 2008 to March of 2018, the average rate of sea level rise accelerated further to 4.3 mm per year.

The net takeaway is that the rate of global ocean rise has increased by more than 50 percent since the early 1990s and that this acceleration has been driven by increasing melt from large land glaciers like those in Greenland and Antarctica.

(Sea level rise contributors as reported by the World Meteorological Organization in its 2017 report on the state of the global climate.)

Over the coming years and decades, this rate of rise is likely to continue to accelerate — surpassing 5 mm per year sometime rather soon, and likely exceeding the 1 cm per year mark by the 2040s through the 2060s. Melt rates will likely increase substantially as we approach the 1.5 C and 2.0 C warming marks. However, the net heat pressure from fossil fuel emitted greenhouse gasses will also drive sea level rise rates. As a result, it is imperative that we work to cut fossil fuel emissions more rapidly and that we pursue a swift as possible transition to clean energy.

May Arctic Warming Event Follow-up — Not So Bad as Predicted, But Worries Remain for Early June

There are many reasons why we monitor Arctic sea ice melt during summer. First, sea ice is a key climate indicator. Second, we are in a period of time where ice-free Arctic conditions are becoming more possible as global temperatures keep rising. And third, falling levels of Arctic sea ice have knock-on effects for a number of climate systems that we all rely on.

(Will we see a warmer than normal early June for the Arctic Ocean? If we do, it could seriously impact the Arctic Ocean’s remaining and thinning sea ice.)

Last week, we pointed out that GFS models were predicting a very warm spike to around 3.5 C above average temperatures for the Arctic come late May. Thankfully, due to the model running a bit hot, such extreme readings did not emerge. However, temperatures over the Arctic Ocean remained about 0.85 C above average overall for the past 7 day period.

Consistent, though somewhat mild, warmer than normal temperatures for this time of year over the Arctic during 2018 are still somewhat worrisome. Recent very warm winter years have experienced ‘saving grace periods’ during May and June in which temperatures near the pole returned to near average or slightly below average.

(Above freezing or near freezing temperatures predicted for most of the Arctic Ocean on June 4, 2018 in the GFS model. Sea ice tends to start melting at around -2 C due to the salt content in surrounding ocean waters. During recent years, the Arctic sea ice has been far weaker and thinner than historic norms. Image source: Earth Nullschool.)

This is not the case for 2018 so far. Temperatures have tended to remain warmer than average for the Arctic Ocean and near the pole throughout May. Moreover, short range forecasts indicate that the critical time period of early June could see continued above average temperatures — providing a potential kick for sea ice losses come late season.

Overall, GFS model runs indicate that temperatures will remain in a range between 0.5 and 1.3 degrees Celsius above average for the Arctic over the next five days. These above normal temperatures pose increased risk for sea ice losses during the crucial June window. June weather tends to greatly influence late season sea ice totals. A warmer than normal June will produce higher numbers of melt ponds and greater impetus for melt to continue with force through July, August, and September. Cooler and often cloudier Junes have tended to protect late season sea ice from hitting new all time record lows.

(Weekly averages for the Arctic Ocean during early June are expected to range near 1 C warmer than normal — extending what has already been a warmer than normal May. Image source: Global and Regional Climate Anomalies.)

2018, so far, has seen a warmer than normal May for the Arctic Ocean. And so we see ice getting swept back behind traditional lines in the Chukchi Sea, in the Beaufort Sea, and in the region north of Svalbard. Peripheral areas like Baffin Bay, Hudson Bay, and the south Kara Sea have seen slower ice melt due to their co-location with trough zones. But it is Central Arctic melt that we should be more concerned about. So we’ll be closely monitoring this region as May runs into early June.

 

Odd and Dangerous Mekunu Bears Down on Oman

This year, two tropical cyclones have sprung up in the Western Arabian Sea. A region where, according to our understanding of climate, “storms do not form.” Well, the climate has clearly changed. Because a storm is raging there now. And for Oman today, these changes bring with them serious threats to life and property.

(Discussion of how climate change has altered tropical cyclone formation and intensity dynamics in the Western Arabian Sea during 2018.)

About five days ago, tropical storm Sagar formed east of Somalia in the Western Arabian Sea near the Gulf of Yemen. The storm was notable due to the fact that it was the furthest west a storm had ever formed in this region, according to records. The storm then dumped copious amounts of rainfall over Somalia — resulting in the loss of 34 lives.

Just a few days later, a second storm, Mekunu formed in about the same region. Tracking north, it is now threatening Oman with the potential to hit category 2 intensity. Unlike Sagar, Mekunu poses a triple threat due to expected very heavy rainfall, large waves, and storm surge.

(Mekunu rages south of Oman and Yemen after forming in the Western Arabian Sea. Image source: NASA.)

The region near Salalah Oman that the storm is barreling toward — typically receives just five inches of rainfall per year. But Mekunu could deliver two to five times that amount (or more) in just a few days. Moreover, the flat coastal plain is backed by mountainous terrain to the north. The higher land produces lift that will intensify expected rainfall. And current models predict that more than two feet of water (24 inches) could fall on up-sloping regions facing Mekunu’s advance. What’s notable is that these totals keep rising and that peak local totals for the storm in the NOAA NCEP model show some ridiculous amounts — up to 74 inches (see below).

Why are peaks in this model so high? First, sea surface temperatures are very extreme throughout the region. In the immediate vicinity of Mekunu, ocean surfaces range from 30 to 32 degrees Celsius. The waters are about 1 to 2 C above normal and are thus providing Mekunu with a lot more moisture than is typical. However, the larger environment that Mekunu is feeding off of also has much higher than typical moisture loads. For one, sea surfaces east of Somalia have spiked to as much as 5 C above average recently — pumping out great loads of evaporation. Further, moisture levels over the Arabian Peninsula are high due to moisture streaming in along a rather intense subtropical Jet Stream moving over the also much warmer than normal sea surfaces in the Med. The result is a much higher than normal rainfall potential.

(Mekunu presents a very severe rainfall risk for Oman in addition to a predicted strong storm surge and very high waves. Image source: NOAA NCEP.)

Such heavy rains would flush floods of water into lowlands already confronted with high waves and rising seas. According to a recent report by Bob Henson at Weather Underground, wave heights could reach 24 feet along the coast. The same report cites storm surge expert Dr Hal Needham who states:

The significant wave height leads me to think coastal flood potential is a real threat. At some point the water from waves crashing onshore does not have time to drain before the next wave hits. My gut feeling is that we could see a noticeable storm surge that is quite dynamic, with a lot of wave action and rapidly moving water. Expect wave heights to be tremendous.

(Much warmer than normal sea surface temperatures in the Mediterranean and Arabian Seas are helping cyclones to form in atypical regions even as they are lending fuel to their intensification. Image source: Earth Nullschool.)

Mekunu’s intensity is certainly quite high. And it is one of a recent spate of storms to impact the region. With research showing that the intensity of storms in the Arabian Sea has increased during the past 20 year period. However, the far western formation of Mekunu and Sagar add a new twist to the story. For it appears that the zone of storm formation is also shifting westward as sea surface temperatures rise and, apparently, Jet Stream changes have the potential to deliver higher levels of atmospheric moisture to the Arabian Peninsula. All of these factors feed both storm formation and intensity potentials.

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.

 

Globe Just Experienced its Third Hottest April on Record

According to reports from NASA GISS, the world just experienced its third hottest April on record. Topping out at 0.86 degrees Celsius above NASA’s 20th Century baseline, April of 2018 edged out 2010 as third in the record books despite the ongoing natural variability based cooling influence of La Nina.

(Analysis of present global temperature anomalies with information provided by NASA, NOAA and Earth Nullschool.)

The warmest regions of the world included large sections of the lower Arctic — encompassing Eastern Siberia, the East Siberian Sea, and the Chukchi Sea. In addition, Central Europe experienced much warmer than normal conditions. Notable cool pools included North-Central North America, the High Arctic, and the Weddell Sea region of Antarctica.

A seasonal reinforcement of the Jet Stream helped to keep cold air sequestered in the High Arctic during April. However, this sequestration appears to be weaker compared to recent April-through-June periods as record warm spikes returned to the High Arctic during early May. The result of strong south-to-north heat transfer through various ridge zones in the Jet Stream.

(Third warmest April on record despite La Nina. Image source: NASA.)

La Nina remained the prominent natural variability related feature during April. And the cooling influence of La Nina has tamped global temperatures down a bit following the recent record hot year of 2016. Overall, it appears that global temperatures are on track to average between 1.04 C and 1.08 C above 1880s averages during 2018. These rather high excessions are, of course, caused by atmospheric greenhouse gasses peaking in the range of 410 ppm CO2 (around 491 ppm CO2e) during April, May and June. Representing the greatest concentration of heat trapping gasses on Earth in about 15 million years.

With La Nina fading, its cooling influence is likely to become less acute and global temperatures may again begin to ramp higher by mid to late 2018. NOAA has indicated a 50 percent chance for El Nino formation during late 2018. If 2018-2019 does see an El Nino emerge, global temperatures will likely again exceed the 1.15 C threshold and potentially challenge 1.2 C.

(A warm Kelvin Wave crossing beneath the Equatorial Pacific brings with it the potential for El Nino formation during 2018-2019. If El Nino does form, and with atmospheric greenhouse gas concentrations so high, it is likely that we would see temperatures comparable to the record global warmth of 2016 re-emerge. Image source: NOAA.)

However, it is unlikely that the weaker predicted El Nino, if it does emerge, will force temperatures considerably higher than levels achieved during the strong El Nino of 2016. For that, we will likely have to wait until the early 2020s. But with carbon emissions continuing near record high ranges, temperatures are bound to rise — with the 1.5 C threshold likely to be breached by the late 2020s or early 2030s.

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.

Global Sea Level Rise Accelerated to 4.6 mm Per Year After 2010

Human forced climate change through fossil fuel burning now presents a serious threat to the world’s coastal cities and island nations. Diverse regions of the world are now facing increased inundation at times of high tide and during storms. Unfortunately, this trend is only worsening. And depending on how much additional fossil fuel is burned, we could see between 2 to 10 feet or more of sea level rise this Century.

(Sea level rise analysis and update based on information provided by AVISO, Climate Reanalyzer, and the work of Dr. James Hansen.)

As the Earth has steadily warmed to 1.1 C above 1880s averages, the oceans of our world have risen. At first, the rate of rise was very mild — a mere 0.6 mm per year during the early 20th Century. However, as the rate of global warming increased and the oceans took in more heat, the middle 20th Century saw sea level rise increase to 1.4 mm per year. By the end of the 20th Century, the polar glaciers had begun to melt in earnest. And from 1990 to the present day, the rate of sea level rise has accelerated to 3.3 mm per year.

Due to more warm water invading the basal regions of glaciers and more ice bergs calving into the world ocean, the annual rate at which ocean levels increase continues to jump higher. And during recent years — from 2010 to 2018 — the world ocean has risen by nearly half a centimeter each year (4.6 mm).

Global Sea Level Rise 4.6 mm Per year

(Since 2010, the rate of sea level rise has again accelerated. And it appears that El Nino years have recently tended to produce strong upward swings in the annual rate of increase. This may be due to El Nino’s tendency to set up stronger cycles of energy transfer to the poles. NOAA presently indicates a 50 percent chance that a mild to moderate El Nino will emerge during the winter of 2018-2019. Will we see another sea level spike at that time should El Nino emerge? Image source: AVISO.)

Now both island nationals and coastal cities face the increasing danger of rising tides, of inundation, and of loss of lands and infrastructure. A rapid switch to renewable energy and away from fossil fuel burning is needed to save many regions. However, due to presently high greenhouse gas accumulation, it is likely that some zones will be lost over the coming decades.

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.

Major Arctic Warming Event Predicted For the Coming Week

It’s been consistently, abnormally, warm in the Arctic for about as long as any of us can remember. But during recent years, the changes — caused by a massive and ongoing accumulation of heat-trapping gasses in the Earth’s atmosphere — appear to be speeding up.

(Far above normal temperatures are expected to invade the Arctic this week. The likely result will be an acceleration of sea ice melt and retreat. Image source: Global and Regional Climate Anomalies.)

This week, two major warm air invasions — one issuing from Siberia and another rising up through the Fram Strait and extending north of Greenland are expected to bring locally 10-20 C above normal temperatures and accelerate early season sea ice melt in an already reeling Arctic.

Consistent Warmth, Record Low Sea Ice

The farthest north region of our world has just come out of a winter during which sea ice extents consistently entered never before seen daily low ranges. With the advent of spring, sea ice measures have rebounded somewhat from winter record lows. However, according to Japan’s Polar Research Division, we are presently experiencing the second lowest daily sea ice extents since consistent measurements began. Meanwhile, Greenland during April saw an odd early bump in surface melt.

Overall, the pattern has been one of consistent abnormal warmth. And over the coming week, a number of warm air invasions will infringe upon the typically cold early May Arctic — testing new boundaries yet again.

(An ice-free Bering Sea, open water invading the Chukchi, and fractured sea ice over the Beaufort are notable features for melt season start during May of 2018. Image source: NASA.)

Much of the heating action this year has occurred over the Bering and Chukchi seas — which have never seen so much ice lost. Already sea ice is greatly reduced through these regions. Open water extends far into the Chukchi — onward and north of Barrow, Alaska. Still further into regions in which sea ice is typically rock-solid during this time of year, the Beaufort is experiencing its own late April break-up. But the areas that are expected to see the greatest warming over the coming days run closer to Siberia and the Atlantic.

Major Spring Warm Air Invasion

Today, a wedge of above-freezing air is invading the Laptev Sea north of Central Siberia. Strong southerly winds issuing from Central Asia are running north into the Arctic Ocean. They bring with them 10 to 20 C above average temperatures for this time of year — which is enough to push readings as high as 35 degrees F (2 C) over what during the 20th Century would have been a solid fringe of the polar ice cap.

Over the next 24 hours, this leading edge of warm air will spiral on toward the East Siberian Sea — bringing above freezing temperatures and liquid precipitation with it.

(5-Day forecast maximum temperatures show considerable warm air invasions proceeding throughout the Arctic. In many cases, temperatures near the North Pole will be warmer than regions far to the south. An impact of the warming world ocean on the Arctic environment. Image source: Climate Reanalyzer.)

But the main warming event for the Arctic this week will occur in the region of the Fram Strait east of Greenland. A strong low pressure system near Iceland is expected to drive wave after wave of much warmer than normal air north into the Arctic. This warm air thrust will bring with it temperatures in some places that exceed 20 C above average. Overall, Arctic Ocean basin temperatures are expected to average more than 2.3 C warmer than normal for the entire first week of May. Such high temperature departures are particularly notable for this time of year — as Arctic thermal variance tends to moderate during spring and summer.

The system will push above freezing temperatures deep into the Arctic — generating a repeat of the strange flip-flop that has become so common recently where temperatures near the North Pole are much warmer than readings further south. Warmer than freezing temperatures will also over-ride coastal portions of northeastern Greenland in yet another odd aspect of the event.

Warm storm effects including gale force winds and waves of 8-12 feet will provide added effect to above freezing temperatures in impacting the sea ice throughout the Fram Strait and northeast Greenland region. Increased insolation due to sunlight spreading over the region will also add to the overall potential for melt.

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