September has arrived and it’s time to start speculating about when and at what level this summer’s minimum Arctic sea ice extent will occur. Here’s a helpful summary of previous years’ JAXA AMSR2/AMSR-E extent minima courtesy of Zack Labe:
Here too is JAXA’s current graph of extent, including a selection of previous years:
JAXA extent on August 31st was 4.96 million km2, marginally below last year’s value of 4.99 million km2 on the same date.
Of course JAXA isn’t the only organisation that produces graphs of Arctic sea ice extent! Here too is the NSIDC’s 5 day average extent:
The coarser resolution of the SSMIS instrument produces a higher value for extent, 5.256 million km2 on August 31st compared to 5.169 million km2 last year.
Then there are some European sea ice extent metrics. Here’s the EUMETSAT OSI-SAF SSMIS based extent. 5.67 million km2 on August 31st compared to 5.56 million km2 last year.:
Here too is the Alfred Wegener Institute / University of Bremen AMSR2 based extent. 5.20 million km2 on August 31st compared to 5.11 million km2 last year.:
Finally, for the moment at least, here are the end of August numbers for the “high resolution” AMSR2 metrics:
Extent on August 31st 2022 was 4.76 million km2 compared to 4.66 million km2 on the same date last year.[Edit – September 14th]
JAXA and NSIDC daily extent are both still declining, so 2022 is certainly not going to deliver the earliest minimum in the satellite record. The areas of open water north of 85 degrees are freezing over:
However according to AWI’s high resolution AMSR2 metric overall Central Arctic extent is still declining, so perhaps we will have to wait a while longer for this years minimum?[Edit – September 21st]
The NSIDC have almost called the minimum:
The sun is about to set for the winter at the North Pole, and so the 2022 sea ice melt season is coming to an end. As of September 19, 2022, Arctic sea ice extent stood at 4.68 million square kilometers (1.81 million square miles), placing it ninth lowest in the satellite record for the date. The high-latitude polynyas have frozen over.
P.S. Now confirmed:
On September 18, Arctic sea ice likely reached its annual minimum extent of 4.67 million square kilometers (1.80 million square miles). The 2022 minimum is tied for tenth lowest in the nearly 44-year satellite record, with 2018 and 2017. The last 16 years, from 2007 to 2022, are the lowest 16 sea ice extents in the satellite record.
Watch this space!