Tag Archives: AMSR2

Facts About the Arctic in May 2022

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By way of a change we’ll start the month of May with a closer look at one of the ice mass balance buoys deployed in the Beaufort Sea last Autumn. IMB buoy 569620 was deployed at 78.5 N, 147.0 W on September 3rd 2021, and since then it has drifted to 81.0 N, 147.7 W. Here is the buoy’s record of atmospheric conditions above the ice floe it’s embedded in since then:

Here too is the buoy’s record of the temperature of the ice floe itself, as well as the thickness of the ice and the snow layer covering it:

There’s a few things to note at first glance. The ice floe continued to decrease in thickness into November. It’s thickness then started to increase, but is currently still less than 2 meters. Also the snow depth has gradually been increasing, and (apart from some data glitches!) is now ~38 cm. Finally, for the moment at least, the ice surface temperature has been slowly warming since mid February and is now ~-11 °C.

Returning to more familiar territory, high resolution AMSR2 Arctic sea ice area has taken a bit of a tumble recently:

followed less steeply by extent:

Not unexpectedly, the Pacific periphery is currently leading the decline:

[Edit – May 4th]

The Rutgers Snow Lab has updated its northern hemisphere snow cover bar chart for April 2022:

The May edition of the NSIDC’s Arctic Sea Ice News has also just been published. It summarises April 2022 as follows:

Average Arctic sea ice extent for April 2022 was 14.06 million square kilometers (5.43 million square miles). This was 630,000 square kilometers (243,000 square miles) below the 1981 to 2010 average and ranked eleventh lowest in the 44-year satellite record.

Extent declined slowly through the beginning of the month, with only 87,000 square kilometers (33,600 square miles) of ice loss between April 1 and April 10. The decline then proceeded at an average pace for this time of year through the reminder of the month.

During April, temperatures at the 925 mb level (about 2,500 feet above the surface) over the Arctic Ocean were above average. Most areas were 2 to 3 degrees Celsius (4 to 5 degrees Fahrenheit) above average, but in the Beaufort Sea, April temperatures were up to 5 to 6 degrees Celsius (9 to 11 degrees Fahrenheit) above average:

This was accompanied by a strong Beaufort High pressure cell through the month:

The NSIDC’s update also refers to the Chukchi Sea polynya we’ve been keeping an eye on here:

Strong offshore winds over the northwest coast of Alaska led to openings in the ice cover, called polynyas. The first pulse of winds began on March 21. At that time, surface air temperatures were still well below freezing, and the water in the coastal polynya quickly refroze. By April 9, the offshore push of the ice ceased and the polynya iced over completely.

However, starting on April 12, a second round of offshore wind pushed the ice away from the coast, initiating another polynya. Refreezing began anew in the open water areas, but the ice growth was noticeably slower, reflecting the higher surface air temperatures by the end of the month

The NSIDC also updated their graph of sea ice age, on this occasion for the week of March 12th to 18th over the years:

Arctic sea ice news concludes with brief news of the recent death of Canadian Arctic scientist David Barber. CBC News’s obituary for David provides more details:

Family and friends are mourning the loss of the visionary Arctic researcher and University of Manitoba professor David Barber.

Barber, who was a distinguished professor, the founding director of the Centre for Earth Observation Science and  associate dean of research in the faculty of environment, earth and resource, passed away on Friday after suffering complications from cardiac arrest.

Barber, 61, is survived by his wife Lucette, three children and two grandchildren.

David Barber (left) pictured with his team on an Arctic expedition.  Photo: Julien Barber

[Edit – May 9th]

The waters of the Mackenzie River are starting to spread over the fast ice off the delta:

“False colour” image of the Beaufort Sea on May 7th from the MODIS instrument on the Terra satellite

[Edit – May 11th]

The Polar Science Center at the University of Washington has released the PIOMAS volume data for April 2022:

Average Arctic sea ice volume in April 2022 was 23,000 km3. This value is the 9th lowest on record for April, about  2,300 km3 above the record set in 2017.   Monthly  ice volume was 30% below the maximum in 1979 and 15% below the mean value for 1979-2021. Average April 2022 ice volume was 1.45 standard deviations above the 1979-2021 trend line.

The daily volume numbers reveal the PIOMAS maximum volume for 2022 to be 23,225 km3 on April 26th.

The PSC report continues:

Ice growth anomalies for April 2022 continued to be at the upper end of the most recent decade with a mean ice thickness (above 15 cm thickness) at the middle of recent values.

The ice thickness anomaly map for April 2022 relative to 2011-2020 divides the Arctic in two halves with positive anomalies in the “Western Arctic”  but negative anomalies in “Eastern Arctic”. A narrow band of negative anomalies remains along the coast of North Greenland but a positive anomaly exists north of Baffin Island.

Note that the “positive anomaly north of Baffin Island” referred to is not apparent in the CryoSat 2 ice thickness anomaly map, although there is agreement about the thicker ice in the eastern Beaufort Sea:

[Edit – May 23rd]

CryoSat-2 thickness maps stopped for the Summer in mid April. I’ve been hoping for mid May data from the PIOMAS team, but in vain so far. In its continuing absence here is a “work in progress” PIOMAS thickness map for the end of April:

The sea ice in Chaunskaya Bay and along the adjacent coast of the East Siberian Sea is starting to look distinctly damp:

“False colour” image of the East Siberian Sea on May 23rd from the MODIS instrument on the Terra satellite

That’s not too surprising when you also look at recent temperatures in Pevek, which have been approaching all time highs for the date:

P.S. The Mackenzie River has reappeared from under the clouds and is now largely liquid:

“False colour” image of the Mackenzie River and Beaufort Sea on May 23rd from the MODIS instrument on the Terra satellite

[Edit – May 27th]

Some surface melt is now visible on the fast ice at Utqiaġvik:

No doubt the recent above zero temperatures are responsible, but the forecast is for colder conditions to return:

Discussion continues on the new open thread for June 2022.

Facts About the Arctic in March 2022

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For detailed analysis of Arctic sea ice extent over the next few weeks please see the 2022 maximum extent thread. However to get the new open thread going here is the current JAXA/ViSHOP extent graph:

It’s looking more and more as though the real maximum for 2022 occurred close the false peak on February 23rd.

Arctic sea ice volume will keep increasing for a while longer. Here is the current AWI CryoSat-2/SMOS volume graph:

The recent “flat line” in extent is in part due to recent events on the Pacific periphery of the Arctic. Take a look at this animation of AMSR2 sea ice concentration:

The gap varies depending on how the wind blows, but there is still evidence of open water (or very thin ice) along the shore of the Beaufort and Chukchi Seas. Here’s the Mackenzie Delta and the adjacent Beaufort Sea on March 5th:

Continue reading Facts About the Arctic in March 2022 →

Facts About the Arctic in February 2022

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Following the “Great Arctic Winter Cyclone” towards the end of January, here are the latest high resolution AMSR2 area and extent graphs:

The sudden reduction in sea ice area due to the cyclone is very apparent, as is the subsequent refreeze of the affected area. Here’s an animation of AMSR2 concentration revealing more detail:

Here too is the latest AWI CryoSat-2/SMOS Arctic sea ice volume graph:

It doesn’t reveal a similar “blip” towards the end of January, suggesting that reduction in area was due to compaction rather than melt. The current AWI thickness map shows the freshly formed ice north east of Svalbard is still very thin:

The latest thickness anomaly map from the Finnish Meteorological Institute shows that the ice which was exported from the Central Arctic via the Fram Strait is nevertheless still anomalously thin, although there is now an area of thicker ice north of Greenland:

Continue reading Facts About the Arctic in February 2022 →

Facts About the Arctic in January 2022

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2021 has been and gone, so first of all may I wish all our readers a very Happy New Year.

Sadly it’s not been a happy start to 2022 for the inhabitants of Boulder, Colorado, home of the National Snow and Ice Data Center. According to the Denver Post:

The Marshall fire destroyed an estimated 991 homes in Boulder County, damaged 127 more and may have killed three people, Sheriff Joe Pelle said Saturday afternoon.

Pelle added that the cause of the fire — the most damaging in Colorado history — remains under investigation, and confirmed that sheriff’s officials have served a search warrant on at least one property based on a tip.

Currently, two people are missing in Superior and another is missing in the Marshall area, Pelle said. All three are feared dead as each of their homes was lost to the fire, the sheriff said…

So far, officials say Thursday’s wildfire — exacerbated by 100-mph winds — burned more than 6,000 acres across Boulder County.

The fire destroyed 553 homes in Louisville, damaging 45, Pelle said Saturday. It also destroyed 332 homes in Superior, damaging 60 in that town, and destroyed 106 homes in unincorporated Boulder County, damaging 22…

Officials first thought downed power lines sparked the fire, but have been unable to confirm its origin. The abnormally dry conditions led to what is now the most destructive wildfire in Colorado history.

Moving north to examine snow and ice data from the Arctic, let’s start 2022 in traditional fashion with a look at high resolution AMSR2 area and extent:

Both metrics are now near the upper boundary of the last 10 years’ range. The AMSR2 instrument wasn’t launched into orbit until summer 2012, but according to both JAXA and NSIDC data extent on January 1st 2022 is almost identical to the same date in 2012. Regular readers will recall that year went on to produce the lowest annual minimum extent in the satellite era despite recording the highest annual maximum in the decade of the 2010s:

Note that sea ice volume tells a rather different story. Here’s the latest AWI CryoSat-2/SMOS volume graph:

The current near real time data is likely to be revised upwards slightly when the final reanalysis is complete, but even so volume seems likely to remain in the lower half of the recent range at the end of 2021.

Here too is the AWI Arctic sea ice thickness map:

together with the thickness anomaly map from the Finnish Meteorological Institute:

Once again the ice in the so called “last ice area” north of Greenland and Ellesmere Island is thinner than usual, as is the ice in the Fram Strait and East Greenland Sea.

[Edit – January 11th]

As has been pointed out below, the Polar Science Center has now released the PIOMAS volume data for December 2021:

Average Arctic sea ice volume in December 2021 was 13,300 km3. This value is the 9th lowest on record for December,  about  2100 km3 above the  record set in 2016.   Monthly  ice volume was 51% below the maximum in 1979 and 37% below the mean value for 1979-2020. Average December 2021 ice volume was  1.2  standard deviations above the 1979-2020 trend line.

November and December of 2021 saw relative rapid ice growth  for recent years, bringing the mean ice thickness  (above 15 cm thickness) towards the thicker end of  the recent values.

The ice thickness anomaly map for December 2021 relative to 2011-2020 continues to show anomalies divided into positive and a negative halves with areas of positive anomalies increasing since the two prior months and stretching from the Beaufort, over the pole and into the Barents.  Negative anomalies stretching from Fram Strait,  North of Greenland and along the Canadian Archipelago. Areas North of Greenland again feature low ice thickness as in prior years.

Note that as revealed by this animation from NASA Worldview the sea ice in the Lincoln Sea is currently still breaking up and being exported from the Central Arctic via the Nares Strait:

[Edit – January 25th]

The Atlantic side of the Arctic Ocean has been taking a bit of a battering from what I shall henceforth refer to as the Great Arctic Winter Cyclone of 2022, or GAWC 2022 for short. Unless there’s an even deeper one later in the year of course!

According to the Canadian Meteorological Centre the storm achieved a minimum Mean Sea Level Pressure of 937 hPa at 12 noon UTC yesterday:

Here are the visible effects of the storm on the sea ice in the area so far, now updated to January 25th:

Watch this space!

Facts About the Arctic in December 2021

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Christmas is coming. Santa’s secret summer swimming pool has frozen over. The time has come for a new monthly Arctic update.

The JAXA/ADS/ViSHOP web site is undergoing maintenance for a week, so let’s start the festive season with a look at high resolution AMSR2 area and extent:

After a brief hiatus in early November both metrics are once again tracking within, but near the upper bound of the last 10 years.

Next let’s take a look at the latest AWI CryoSat-2/SMOS thickness map:

together with the anomaly map from the Finnish Meteorological Institute:

Still thinner than usual in the so called “last ice area” north of Greenland and Ellesmere Island, and thicker than usual on the Siberian side of the Arctic, particularly in the Chukchi Sea.

Finally, for the moment at least, here’s the latest CryoSat-2/SMOS volume graph:

Unlike the previous metrics, this particular one is close to the middle of the pack.

[Edit – December 5th]

The National Snow and Ice Data Center issued their latest monthly Arctic Sea Ice News update earlier than usual this month:

Sea ice extent increased at a faster than average pace through November and by the end of the month, extent was just within the interdecile range. Extent was above average in the Bering Sea, but Hudson Bay remained unusually ice free through the month.

The November 2021 monthly average extent was 9.77 million square kilometers (3.77 million square miles), which ranked tenth lowest in the satellite record. The 2021 extent was 930,000 million square kilometers (359,000 million square miles) below the 1981 to 2010 long-term average. Extent was higher than average in the Bering Sea, but is extremely low in Hudson Bay.

Air temperatures at the 925 millibar level (about 2,500 feet above the surface) were well above average north of the Canadian Archipelago, by as much as 6 degrees Celsius. Conversely, temperatures over southwest Alaska and the eastern sector of the Bering Sea were as much as 6 degrees Celsius below average:

The sea level pressure pattern for November featured widespread low pressure over the Atlantic side of the Arctic and extending into the Barents and Kara Seas, paired with a moderately strong Beaufort Sea High. Strong low pressure over the Gulf of Alaska resulted in a circulation pattern in the eastern Bering Sea that brought cold air from the north. This pattern was favorable for sea ice growth, and can explain the above average ice extent in the region:

[Edit – December 7th]

Since the start of December high resolution AMSR2 extent has been flatlining:

Sea ice area has even declined slightly over the past few days:

Here too is an animation created by Uniquorn on the Arctic Sea Ice Forum using AWI ASMR2 data to reveal ice movement through the Nares Strait during December:

[Edit – December 9th]

The JAXA/ADS/ViSHOP web site is down again, so let’s take another look at high resolution AMSR2 area and extent:

It seems that the “brief hiatus” is over, and extent is now in a “statistical tie” with 2018/19 at 4th lowest for the date amongst recent year.

[Edit – December 13th]

The PIOMAS Arctic sea ice volume data for November 2021 has been released:

Average Arctic sea ice volume in November 2021 was 7,830 km3. This value is the 7th lowest on record for November,  about  1600 km3 above the  record set in 2016.   Monthly  ice volume was 61% below the maximum in 1979 and 45% below the mean value for 1979-2020. Average November 2021 ice volume was about one sigma above the 1979-2020 trend line. October saw relative rapid ice growth  for recent years bringing the mean ice thickness  (above 15 cm thickness) above the recent low values: 

The ice thickness anomaly map for November 2021 relative to 2011-2020 continues to show anomalies divided into positive and a negative halves with areas of positive anomalies increasing since the two prior months. Negative anomalies stretching from North of Greenland and along the Canadian Archipelago across the Eastern Arctic into the Barents Sea. Areas North of Greenland again feature very low ice thickness as in prior years (see our recent paper).  Positive anomalies are notable in the Beaufort and Chukchi seas due to advection of thicker older ice into the areas during the previous winter (See recent paper on this). The Alaskan summer has also been relatively cold contributing to unusually thick ice in this area:

CryoSat-2 ice thickness shows a similar picture sea ice thickness anomalies but with the maxima slightly displaced which maybe due to temporal sampling of the composite:

The JAXA web site is still down, so here’s another set of high resolution AMSR2 graphs:

[Edit – December 14th]

NOAA have just released their 2021 Arctic Report Card. Here’s the introductory video:

and here is the report itself:

[Edit – December 18th]

Ice hardened LNG tanker Vladimir Vize is about to enter the Vilkitsky Strait on the Northern Sea Route:

Meanwhile Science.org reports that “The Arctic is warming four times faster than the rest of the world“:

“Everybody knows [the Arctic] is a canary when it comes to climate change,” says Peter Jacobs, a climate scientist at NASA’s Goddard Space Flight Center, who presented the work on 13 December at a meeting of the American Geophysical Union. “Yet we’re misreporting it by a factor of two. Which is just bananas.”

Jacob’s co-authors include researchers who oversee several influential global temperature records, and they noted the faster Arctic warming as they prepared to release the global temperature average for 2020. NASA’s internal peer reviewer challenged the higher figure, suggesting the scientific literature didn’t support it. But the researchers have found the four times ratio holds in record sets from both NASA (3.9) and the United Kingdom’s Met Office (4.1), and they hope to soon include the Berkeley Earth record. (Their work also has company: In July, a team at the Finnish Meteorological Institute posted a preprint also arguing for the four times figure.)

The researchers found Arctic warming has been underestimated for a couple of reasons. One is climate scientists’ tendency to chop each hemisphere into thirds and label the area above 60°N as the “Arctic”—an area that would include, for example, most of Scandinavia. But the true definition of the Arctic is defined by Earth’s tilt. And, as has been known for centuries, the Arctic Circle is a line starting at 66.6°N. When researchers lump in the lower latitudes, “you’re diluting the amount of Arctic warming you’re getting,” Jacobs says. “That is not a trivial thing.”

The other difference is the choice of time periods over which the warming rate is calculated. Jacobs and his colleagues focused on the past 30 years, when a linear warming trend emerged for the Arctic. Analyses that look at longer term trends see less divergence between the Arctic and the world.

[Edit – December 23rd]

Here is the latest CryoSat-2/SMOS volume graph, now including some reanalysed data which seems to have come in slightly higher than the earlier “near real time” numbers:

Plus the AWI thickness map:

Further discussion of the divergence between volume and extent continues in the new New Year 2022 thread:

Facts About the Arctic in November 2021

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It’s not November until tomorrow, but Andy Lee Robinson has just published the 2021 edition of his long running “Arctic ice cube” video series, based on the PIOMAS volume data. Here it is for your edification:

You may also wish to keep tabs on our deep dive into CERES top of the atmosphere energy flux data. Here’s a sneak preview:

[Edit – November 3rd]

In stark contrast to other recent years, northern hemisphere snow cover is very low at the moment:

Continue reading Facts About the Arctic in November 2021 →

Facts About the Arctic in October 2021

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By way of a change we start this month’s look at all things Arctic with some sea ice statistical analysis. Anthony Watts’ Arctic porky pie production line has been speeding up recently, and I am not the only one who has noticed. As part of his takedown of the latest “skeptical” allegations against the United Kingdom Met Office Tamino has been looking at trends in Arctic sea ice extent over at his “Open Mind” blog:

First and foremost, the yearly minimum is only one day out of the year. We have sea ice extent data throughout the year, and what happens during the rest of the year counts. Instead of using the annual minimum, let’s use the annual average. To avoid losing the most recent data, I’ll compute the yearly average for October through the following September rather than the usual (but arbitrary) January through December. I’ll also omit October 1978 through September 1979 because that year is incomplete. I get this:

The annual averages show much less fluctuation than the annual minima, so we can estimate things like rates of change with greater precision. I find that there is statistical evidence that the rate changed over time. One model of such changes uses three straight-line segments with their changes chosen to best-fit the data, like this:

Continue reading Facts About the Arctic in October 2021 →

Facts About the Arctic in August 2021

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Let’s first of all take a look at JAXA’s flavour of Arctic sea ice extent:

After reaching lowest extent for the date in early July, the weather in the Arctic Basin was stormy, cloudy and cool compared to other recent years until the last few days of the month:

Here’s the same period in 2020 for comparison purposes:

Consequently the rate of extent loss in the second half of July was significantly less than last year.

Next let’s take a look at AMSR2 concentration:

Continue reading Facts About the Arctic in August 2021 →

Facts About the Arctic in July 2021

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The JAXA ViSHOP web site was down for maintenance over the weekend. It is now back in action, to reveal Arctic sea ice extent at the lowest for the date in the AMSR2 record:

[Edit – July 6th]

High resolution AMSR2 area is also now lowest for the date:

as indeed is extent:

[Edit – July 13th]

According to the Canadian Meteorological Centre the current cyclone has bottomed out with a central mean surface level pressure of 971 hPa:

Continue reading Facts About the Arctic in July 2021 →

Facts About the Arctic in June 2021

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Let’s begin the month with a “true colour” image from the Terra satellite of the Laptev Sea and thereabouts:

The blueish tinge indicates the appearance of melt ponds almost everywhere over the land-fast ice currently covering the majority of the Laptev Sea.

Let’s also take a look at the high resolution AMSR2 metrics for the end of May 2021:

Thanks to the recent “brief hiatus” in areal decline, Arctic wide compaction is no longer in record territory:

Finally, for the moment at least, here is the Danish Meteorological Institute’s high Arctic temperature data in the form of a graph of freezing degree days:

For some reason the data file still doesn’t include data to the end of May, but things won’t change much by then. Over the winter as a whole only 2016/17 was significantly warmer.

Let the 2021 Arctic sea ice summer melting season officially begin!

[Edit – June 4th]

Perhaps unsurprisingly the GFS forecast from four days ago hasn’t quite worked out as predicted. The Arctic as a whole is certainly on the warm side, with a +2 C anomaly at this moment:

However the 966 hPa MSLP cyclone predicted for Monday is now forecast to be a mere 978 hPa:

With 3 days to go there is a reasonable chance of it verifying in the “New Arctic” of 2021. As you can see from the map above a large area of the Central Arctic has now lost its snow cover. This is confirmed by the Rutgers Snow Lab northern hemisphere data for May:

A new Sentinel 3 melt pond fraction product from the University of Bremen confirms that on the fast ice in the Laptev & East Siberian Seas snow cover has departed and melt ponds have arrived:

In other news Wipneus has released the latest PIOMAS gridded thickness and volume data on the Arctic Sea Ice Forum:

For some strange reason 2021 volume at the end of May is almost identical to 2012 and 2020! Plus of course there’s the modelled volume export from the Central Arctic via the Fram Strait:

[Edit – June 6th]

This “false colour” image reveals that there’s virtually no snow cover left on land, and this “false colour” image reveals that the land-fast ice in the East Siberian Sea is now awash with melt ponds:

[Edit – June 8th]

The forecast low pressure area appears to have bottomed out near the Severnaya Zemlya islands with a 978 hPa MSLP:

High resolution AMSR2 Arctic sea ice area is now 2nd lowest for the date after 2016:

Laptev sea ice area is still lowest for the data, and looks as though it will retain that position for a while:

[Edit – June 9th]

The effect of the recent heat and wind on the remaining sea ice in the Laptev Sea is now all too apparent:

It’s also evident in the DMI >80N temperature graph, which has now reached sea ice “melting point” ahead of the climatology:

Note that the blue line is actually above the “freezing point” of salty Arctic sea water.

[Edit – June 13th]

Fairly clear skies over the Laptev Sea and the western East Siberian Sea, revealing wall to wall melt ponds and the land-fast ice starting to break up near the coast as well as on the edge of the now open ocean:

Plus yesterday’s view of the Beaufort Sea, revealing fast ice breaking up in the western entrance to the McClure Strait:

[Edit – June 18th]

A clearish view of the Laptev Sea today, revealing assorted cracks in a variety of locations:

[Edit – June 20th]

The latest mid-month PIOMAS thickness/volume numbers have been released:

[Edit – June 23rd]

The skies over the Vilkitsky Strait have been cloudy for a few days. However a fairly clear view yesterday reveals that breakup is well under way in what is usually one the last areas along the Northern Sea Route to become navigable:

[Edit – June 26th]

The land-fast ice in the East Siberian Sea has started to disintegrate en masse:

Data from ice mass balance buoy 441910, currently located at 76.1 N, 151.1 W in the Beaufort Sea, reveals the onset of both surface and bottom melt:

Watch this space!