September daily extents are now fully reported and the 2021 September monthly results can be compared with those of the previous 14 years. MASIE showed 2021 at 5.2M km2 and SII was close behind, reaching 4.9M for the month. Analysis below shows that the 2021 Minimum was 1/2 Wadham ( 1M km2) higher than the 14 year average, and 1¼ Wadhams more than 2007
In August, 4.4M km2 was the median estimate for the September monthly average extent from the SIPN (Sea Ice Prediction Network) who use the reports from SII (Sea Ice Index), the NASA team satellite product from passive microwave sensors. The SII actual ice extent was 1/2 Wadham higher.
Note that both MASIE and SII started the month higher than average, hit bottom earlier and then increased the surplus. SII tracked much lower up to ~400k…
October 4, 2021 at 12:44AM