Warm Winds Take Aim at Chukchi as Arctic Sea Ice Volume Hits Record Lows

Temperatures over the Chukchi Sea are predicted to hit as high as 37 degrees Fahrenheit (2.9 C) on Wednesday and Thursday as a massive high pressure ridge building over Alaska pulls warm, moist Pacific air northward. These temperatures represent staggering warmth for this Arctic Ocean zone during March when temperatures are typically about 54 degrees F (30 degrees C) cooler.

Major Warm Wind Invasion for the Chukchi This Week

(Multi-day above freezing temperatures for the Chukchi sea predicted for later this week is not a normal event for early March. Unfortunately, warm wind invasions like this one have become more common as the globe has warmed up due to human fossil fuel emissions. Image source: Earth Nullschool.)

This recent warm wind invasion is one of many observed over the past five years in which enormous bulges in the Jet Stream have pierced deep into what was once a mostly impenetrable pall of winter chill hanging over the Arctic. It’s a new atmospheric condition associated with rampant fossil fuel burning. One that has produced considerable damage to the Arctic environment by reducing sea ice coverage, threatening key species, melting glaciers and thawing permafrost.

Such incursions of extreme warmth bear the obvious marks of a failing of Arctic cold brought on by human-forced climate change and have tended to generate significant spikes in overall Arctic surface temperatures during fall, winter, and spring. This week’s warm air invasion of the Chukchi is expected to help push readings for the entire region above the 66 degree north latitude line to 4.5 C (8 F) above average for this time of year. That’s a strong departure for this region during the month of March when the typically more uniform advance of warmth in the lower latitudes tends to strengthen the Jet Stream — locking in Polar winter conditions in the far north through about the middle of April.

(The warm wind invasion of the Chukchi Sea is expected to help push overall Arctic temperatures considerably higher. Image source: Climate Reanalyzer.)

Far above average Arctic surface temperatures extending from October of 2016 through March of 2017 have been triggered again and again by these floods of warm air rising up from the south. And the net effect on Arctic sea ice volume has been little short of devastating.

Arctic Sea Ice Volume Lowest Ever Recorded During Winter, Comparable to Summer Volumes of the Early 80s

Arctic sea ice volume for both January and February of 2017 are now far below past record low trend lines for this time of year. Present record low monthly values for this past February are around 17,000 cubic kilometers vs previous record lows for the month during 2013 at around 19,500 cubic kilometers. Last February’s sea ice volume average of 17,000 cubic kilometers is about the same sea ice volume measured at the end of melt season in September of 1981. In other words, sea ice volume in winter now is comparable to sea ice volumes during the summers of the early 1980s.

(Arctic sea ice volume has never been this low during winter time. Image source: PIOMAS.)

All the record warmth flooding into the Arctic during 2016 and 2017 has undoubtedly contributed to these new record lows for sea ice volume. And a cooling of the Arctic surface relative to recent record warmth during March and April could soften this worrying trend somewhat. To this point, it is worth noting that sea ice extent measures are now closer to past record low trend lines. So there has been some slightly more hopeful inching back to slightly less ridiculously abnormal measures. A more positive movement that will likely take a hit as Arctic temperatures are predicted to significantly warm again this week.

Weather is Variable, But the Underlying Trend Looks Pretty Bad

Weather, as we should note, can be quite variable and may bring a more pleasant surprise later in the month. However, despite this potential, sea ice states are looking as bad or worse than they ever have at the end of freeze season. And it is worth noting that less ice coverage and volume leaves more dark water open to absorb the sun’s springtime and summer rays and less ice to reflect it. Furthermore, post La Nina periods, as we are now experiencing, tend to flush more atmospheric and ocean heat into the Arctic. So, despite the variable nature of weather overall, we’re in a bit of a situation where the systemic trend odds of a noteworthy sea ice recovery toward more rational trend lines pre-summer 2017 aren’t looking very good.



Arctic Sea Ice Graphs

Earth Nullschool

Climate Reanalyzer



Tropical Tidbits

Chukchi Sea

Summer 2014 Melt Season to Ramp up in Early May Heat Wave: Fixed Jet Stream, Dual Ridges Form Sea Ice Achilles Heel

For many months the weather pattern has been essentially fixed. A ridge over China and Eastern Russia combined with warm air flows over Central Asia to amplify heat from Siberia and on into the Arctic Ocean. On the other side of the Pacific, a harmonic pattern involving warm southerly air flows over Alaska and Western Canada has also transported an inordinate amount of highly anomalous heat into the Arctic.

These warm ridges have been consistently reinforced by high amplitude Jet Stream waves. During the Winter of 2013-2014, these same atmospheric heat transport engines collapsed the polar vortex, causing melt, avalanches, and 60 degree F temperatures for Alaska in January all while pulling Arctic air down over the Eastern United States throughout the winter months.

For Alaska, Western Canada and the Eastern US, it is a general pattern that has now lasted nearly 14 months. A blocking pattern that weather historians everywhere should take note of as a general evidence of atmospheric changes resulting from human-caused warming and a validation in observation to the findings of Dr. Jennifer Francis.

Early Season Melt in the Bering Sea

This warm air flow also severely retarded sea ice formation in the Bering Sea between Alaska and far Eastern Russia throughout winter. Now, this poorly formed ice is rapidly melting out as a barrage of storms and continued warm, southerly air flows result in ongoing degradation. Recent observations show a rather extreme loss of sea ice in this region over the past 18 days:

Bering and Chukchi Seas April 10Bering and Chukchi Seas April 27

(LANCE-MODIS comparison of Bering and Chukchi Sea Ice on April 10 [left image] and April 27 [right image]. Image source: LANCE MODIS. Hat Tip to Arctic Sea Ice Forums Poster Frivolousz21.)

As we can clearly see in the two images above, both snow cover and sea ice have experienced severe losses in this region from April 10 to April 27. Warm southerly winds have continued to push ice northward enhancing melt as temperatures typically remained near or above -2 C (the temperature at which sea ice begins to melt) in most regions. Snow losses amplified warmer than freezing water flows into adjacent ocean basins, also enhancing sea ice losses as land masses continued to warm.

Heat Pulse for Bering, Chukchi, East Siberian and Beaufort Seas

Over the next six days, this general warming trend is expected to spike, bringing with it a front of much hotter than usual temperatures extending along a broad zone of the Arctic Ocean north of Canada, Alaska and East Siberia and nearly reaching the North Pole at maximum extent.

The pulse is expected to bring 18-32 F above average temperatures for this region, pushing daily highs into the mid 30s to mid 40s over the Arctic Ocean and to nearly 50 F over waters directly adjacent to the Alaskan coast. GFS model runs for May 2, 2014 show this powerful warm air invasion, indicated by the wave of green on the map below, extending well into the Arctic Ocean with extraordinarily warm temperatures in the mid-to-upper 60s over a broad swath of Central Alaska:

Arctic Heatwave Friday May 2

(GFS temperature model for May 2, 2014. Image source: University of Maine.)

Such an intense warm pulse will greatly involve the Bering, the Chukchi, the East Siberian and Beaufort Seas. It will likely most significantly impact sea ice in regions of the Bering Sea and near-shore zones of the Chukchi and Beaufort. The early season heat wave may also enhance the ice weakening process throughout the affected zone by softening the sea ice and by creating the potential for melt pond formation.

The Major Impact of Early Season Melt Pond Formation

During May and June, early melt pond formation can have a dramatic impact on sea ice melt much later in the season as the darker pools reduce ice sheet albedo serving as a kind of heat lens that bores down through the ice surface. Eventually, the melt ponds connect, forming larger and larger volumes over the ice face until the sea ice is almost completely overwhelmed. In the last phase, melt breaks down through the ice surface to contact the ocean. At this point, the sea ice is typically splintered into much smaller and disassociated fragments.

A recent paper in the journal Nature has found that a multiplication of such early season melt ponds may well be a predictive indicator of end season sea ice extent, area and volume values come September.

The paper notes:

Our simulations show that melt ponds start to form in May, a maximum extent of 18% is reached in the climatological mean at mid-July, and there are hardly any exposed ponds left by mid-August. The strong interannual variability and the positive trend are striking. Whereas in 1996, the year with the highest September ice extent since 1979, the maximum pond fraction reaches only 11%, in 2012, the year with the lowest September ice extent, up to 34% of the sea ice is covered by ponds.

Neven over at the Arctic Ice Blog recently provided an excellent assessment of the impact of melt ponds which is available here.

Massive interconnection of sea ice melt ponds

(Major expanse of dark sea ice melt ponds in the Chukchi Sea during June of 2010. Image source: The Polaris Project.)

Achilles Heel For the Arctic During the Summer of 2014

The most recent hot pulse for this region may just be the first of many as the spring and summer melt season progresses. Jet Stream patterns continue to remain fixed, delivering much hotter than normal temperatures throughout the Western Canadian, Alaskan, and East Siberian regions. Furthermore, snow cover losses for these regions are particularly well advanced further enhancing the likelihood of warm air invasions from these rapidly heating continental zones. Anomalously large and extreme early season fires may also result in a degree of albedo loss as smoke and soot is drawn northward to darken both remaining snow cover and sea ice.

As such, this zone represents a kind of sea ice Achilles heel as the 2014 melt season progresses. If we do see major losses and a progression toward record melt, it will likely come as a result of extreme weather patterns emerging from the continental zones spanning East Siberia, Alaska and Western Canada.



Arctic Sea Ice Forums

University of Maine

Global Forecast System Model

More on Melt Ponds

September Sea Ice Minimum Predicted By Sea Ice Melt Pond Fraction



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