December 8, 2021

Climate Change News

Saving The Planet

Data on the Arctic in August 2021

First of all, let’s take a look at the taste of the JAXA Arctic Sea Ice Extension:

After reaching its maximum date in early July, the climate in the Arctic Basin was stormy, cloudy and cool compared to other recent years until the last days of the month:

This is the same period of 2020 for comparison purposes:

As a result, the rate of loss of extension in the second half of July was significantly lower than last year.

Here’s a look at AMSR2 concentration:

There is still a stubborn layer of ice northeast of the Kara Sea. Although AMSR2 suggests that there is now an ice-free route through the North Sea Route, this has not yet been confirmed by official Russian maps. This extract is dated August 3:

On the other side of the Arctic, during the winter, a large amount of ice of several years advanced in the Beaufort Sea:

As a result, the thaw has been slow so far this summer:

Here is an image that reveals how the 2021 melting season is unfolding in the Arctic Pacific band, showing the thickness and temperature of sea ice measured by an ice mass balance buoy currently located at 75.15 N, 167.88 W:

By contrast, much of the sea ice that was exported from the central Arctic to the North Atlantic during the winter has already melted:

Two recent publications in the academic journal deal with these facts. According to “Record Winter Winds in 2020/21 Driven Outstanding Arctic Sea Ice Carriage” by Robbie Mallett et al .:

Winter 2020/21 was characterized by abnormally high sea level pressure over the central Arctic Ocean, which caused unprecedented anticyclonic winds over sea ice. This atmospheric circulation pattern drove the oldest sea ice from the central Arctic Ocean to the lower latitude Beaufort Sea, where it is most vulnerable to melting in the next warm season. We suggest that this unusual atmospheric circulation can lead to unusually high losses in the summer from the old Arctic ice reserve.

while according to “Wandel’s accelerated loss of sea ice in the sea points to a change in the last Arctic ice zone” by Axel Schweiger et al .:

The Wandel Sea of ​​the Arctic Ocean is the easternmost sector of the last ice zone, where old, thick sea ice is expected to last longer than anywhere else. However, in August 2020, the area experienced a record low sea ice concentration. Here we use satellite data and experiments from sea ice models to determine what caused this minimum sea ice record. In our simulations there was a multi-year trend of sea ice thinning due to climate change. Natural climate variability expressed as wind-forced ice advection and subsequent melting added to this trend. In the spring of 2020, the Wandel Sea had a mixture of thin, unusual ice in recent years, but this thick ice was not widespread enough to avoid the minimum concentration of sea ice in the summer. With continued thinning, low-frequency sea ice events in the summer are expected. We suggest that the last ice zone, an important refuge for ice-dependent species, is less resistant to warming than previously thought.

The same seems to be happening again in 2021. Here is a satellite image of the sea ice in the Wandel Sea on August 3:

Finally, for now, at least, here is the latest thickness map of PIOMAS:

and volume chart, courtesy of Wipneus at the Arctic Sea Ice Forum:

The PIOMAS model shows the volume as the sixth lowest at the end of July, at 7,057 km³. It also confirms the current lack of thick ice in the Wandel Sea, with the remaining thicker ice concentrated north of the Canadian Arctic archipelago. The following is a comparison of the thickness with the same date as 2012, the year that produced the minimum annual volume of Arctic sea ice extension and volume in the satellite era:

[Edit – August 7th]

Here is the current Arctic CMEMS / neXtSIM Arctic Sea Ice Concentration Forecast at 11:30 pm on August 13:

It will be very interesting to find out if there is actually open water up to 86 ° N in a few weeks.

[Edit – August 21st]

In the middle of the month, the thickness numbers of the PIOMAS grid were published:

With a month or so to reach the minimum volume of Arctic sea ice in 2021, 2021 is currently the 6th lowest on the PIOMAS record.

Here is also the latest AMSR2 concentration map, which reveals large areas of low concentration on the Arctic Pacific side:

It also reveals that, despite previous CMEMS forecasts, open water has not yet reached 85 N, although the ice-free zone in northern Greenland is heading towards this path.

[Edit – August 27th]

As the month of August draws to a close, there is another look at the recent history of the only fully functional seasonal mass balance buoy in the Arctic, which is number 52460 which is currently at 74.91 N, 166.39 O:

It looks like the ice surface has risen for a while, which means some snow has fallen or the buoy has slipped into its mounting hole or a combination of both. The remaining thickness of fairly solid material is ~ 0.66 meters.

The latest AMSR2 concentration map reveals even lower concentration areas than a week ago, including one extending from Kap Morris Jesup to the North Pole:

The extent of high-resolution Arctic sea ice appears to be slowly declining towards the September low:

but a sudden burst in the area reflects the low concentration areas visible on the map above:

Look at this space!

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