Tag Archives: MSLP

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 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 April 2021

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As part of his March PIOMAS gridded sea ice thickness update Wipneus also produced this graph of sea ice export from the central Arctic via the Fram Strait:

So far this winter export has been remarkably subdued, but that has now changed. A persistent dipole with high pressure over Greenland and low pressure over the Barents Sea is generating strong northerly winds in the Fram Strait, and even bringing some April snow showers to South West England:

Precisely how high the pressure has been over Greenland is the subject of much debate. See for example this discussion on the Arctic Sea Ice Forum about whether a new world high pressure record has just been set. Different weather forecasting models have come to very different conclusions about the mean sea level pressure of a high pressure area situated over the Greenland ice sheet, which reaches an altitude of over 3,000 metres. Here’s GFS for example, showing 1097 hPa at 06Z on April 4th:

whereas the Canadian Meteorological Centre synopsis for the same time shows a mere 1070 hPa:

At least all the assorted models agree that the isobars are closely packed over the Fram Strait, and hence some of the thickest sea ice remaining in the Arctic is currently heading towards oblivion in the far north Atlantic Ocean:

Here’s the US Navy’s sea ice drift forecast for Saturday 10th:

Continue reading Facts About the Arctic in April 2021 →

Facts About the Arctic in July 2020

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The new month starts with JAXA extent “lowest for the date in the satellite record” by a whisker:

The high resolution Arctic sea ice area and extent graphs based on the University of Hamburg’s AMSR2 concentration data are also in “statistical ties” for that honour, in records going back to 2013:

The 2020 melting season currently seems to be a game of two (geographical) halves. The sea ice on the Siberian side of the Arctic is currently at record lows:

Whereas the Beaufort Sea is near a record high:

Currently the tell tale signs of surface melt are visible across most of the central Arctic, as are the large number of wildfires across Arctic Siberia:

NASA Worldview “false-color” image of the Arctic on July 1st 2020, derived from the MODIS sensor on the Terra satellite

[Edit – July 4th]

The June 30th PIOMAS gridded thickness numbers have been released, and here are the results of Wipneus’s number crunching:

This month including a visualisation of the increasing negative anomaly:

[Edit – July 6th]

A break in the clouds over the North Pole reveals the onset of surface melt:

NASA Worldview “false-color” image of the North Pole on July 6th 2020, derived from the MODIS sensor on the Terra satellite
NASA Worldview “false-color” image of the North Pole on July 6th 2020, derived from the MODIS sensor on the Terra satellite

[Edit – July 8th]

After a brief hiatus there are once again some ice mass balance buoys installed at assorted locations across the Arctic. Some have ceased to function, but one of the buoys installed as part of the MOSAiC expedition is still sending back data as it heads towards the Fram Strait. Buoy 387850 is currently located at 81.66 N, 4.19 E. Here’s its ice mass balance plot:

As you can see, both surface and bottom melt are well under way, with just over a meter of ice still remaining.

Now let’s take a look at buoy 386840, currently located at 74.30 N, 132.60 W in the Beaufort Sea:

It looks as though the ice thickness has increased, but surely that can’t be right at this time of year? To try and find out I downloaded the raw data and plotted the temperature readings from the buoy’s thermistor string:

It looks to me as though the ice floe carrying the buoy is currently floating on some warm fresh water from a recently drained melt pond, which is confusing the sensor designed to measure the position of the bottom of the ice. There certainly seems to be far less than the claimed “1.653 m snow and ice thickness” still remaining to be melted!

[Edit – July 15th]

A very unusual image. Hardly a cloud in the sky over the North Pole yesterday:

NASA Worldview “false-color” image of the North Pole on July 14th 2020, derived from the MODIS sensor on the Terra satellite

The July 2020 extent “plummet” shows no signs of ending just yet. Here’s the JAXA/ViSHOP version:

[Edit – July 17th]

JAXA AMSR2 extent is now below 7 million km², and the high resolution version is lower still:

As the “Laptev Bite” and the Atlantic periphery of open water extends further towards the North Pole, Central Arctic Basin extent is now also at record lows for the date in the AMSR2 record:

[Edit – July 19th]

Wipneus has crunched the mid month PIOMAS gridded thickness numbers, and here are the results:

Extent is currently lowest in the satellite era by a long way, but modelled volume is only fourth lowest!

Watch this space!

[Edit – July 21th]

At long last there’s a sub 1000 hPa MSLP low pressure area slowly wending its way across the central Arctic:

It seems to have bottomed out at 997 hPa. Perhaps this will inhibit the ongoing “plummet” in extent? JAXA extent fell by 114,342 km2 yesterday.

[Edit – July 23rd]

The Northern Sea Route has opened unusually early this year:

Based on the AMSR2 concentration maps from the University of Hamburg that happened on July 13th. The final choke point, as is so often the case, was the Vilkitsky Strait. According to the charts from the Russian Arctic and Antarctic Research Institute, by the 14th there was a narrow way through occupied by no more than 3/10 concentration ice:

[Edit – July 25th]

A mere three days away, and the GFS and ECMWF forecasts are in agreement, so there is a decent chance this setup will materialise in the real world:

Graphics via Tropical Tidbits

A 972(ish) hPa MSLP cyclone sitting over the ice Beaufort Sea by 12Z on Tuesday.

[Edit – July 27th]

The Sea Ice Prediction Network July forecast for this year’s September minimum extent have been released. Here’s the graphical overview:

This year’s median projected value from the July forecasts of 4.3 million square kilometers is essentially identical to the median from the June forecasts. Quartiles are 4.1 and 4.6 million square kilometers. As was also the case for June, only two projections, both by dynamic models, are for a new record low, below the mark of 3.57 million square kilometers set in 2012. One dynamical model predicts the September sea-ice extent above 5.0 million square kilometers, compared to two in the June report.

Note that the numbers quoted are for the average NSIDC extent across the month of September, not the lowest daily JAXA extent, which I suggested earlier would be “below 4 million km²” this year.

Meanwhile over on Twitter this evening (UTC):

[Edit – July 28th]

The MSLP of the (Great?) Arctic cyclone sank below 970 hPa overnight:

Here’s an early false colour snapshot of how (s)he looks from on high this afternoon (UTC), courtesy of the MODIS instrument on the Terra satellite:

[Edit – July 29th]

First up today we have a more complete “true colour” image of the cyclone doing its worst yesterday, including a fairly clear view in the bottom left corner of the initial damage to the sea ice covering the eastern Beaufort Sea. This one is from the Aqua satellite:

Watch this space!