By Dr Susan Crockford
Officially, the maximum winter sea ice extent for 2024 was 15.01 mkm2, reached on 14 March. At an unimpressive “14th lowest” on record, this is astounding news for the winter following the “hottest year on record.” Undeterred, the US government headline writers at the National Snow and Ice Data Center (NSIDC) today went for “Arctic sea ice reaches a below-average maximum.” Note the long-term average (1981-2010) is only 15.65 mkm2 and 15.01 is within 2 standard deviations (see below, screencapped 14 March 2024).
This is what the sea ice maximum extent of 15.01 mkm2 looked like on 14 March this year:
From NOAA’s 17 January 2024 report on the “hottest year on record” [my bold] on global temperatures:
The year 2023 was the warmest year since global records began in 1850 at 1.18°C (2.12°F) above the 20th-century average of 13.9°C (57.0°F). This value is 0.15°C (0.27°F) more than the previous record set in 2016. The 10 warmest years in the 174-year record have all occurred during the last decade (2014–2023). Of note, the year 2005, which was the first year to set a new global temperature record in the 21st century, is now the 12th-warmest year on record. The year 2010, which had surpassed 2005 at the time, now ranks as the 11th-warmest year on record.
According to today’s data from today’s NSIDC report (shown below), the lowest maximum extents were reached in 2015-2018 (14.82-14.52), with 2016 being an especially warm El Nino year. It makes sense that 2017 was the lowest, since it followed the very warm summer of 2016.
However, the max extent for winter 2023 was not far behind, which is odd considering that according to NOAA, warm La Nina conditions didn’t kick in until June 2023. March ice extent for 2023 (now the 5th lowest) was still being influenced by the cold La Nina conditions that prevailed in 2021 and 2022 (2021 now 8th lowest, 2022 now 11th lowest, at 14.88, not shown).
And now 2024 max extent is the 14th lowest, following the warmest global temperature since 1850 was reached in summer of 2023?
Rarely mentioned is that 2005-2007 (weak El Nino/El Nino years) were all below this year’s extent of 15.01 and 2006 and 2007 were both among the 10 lowest extents listed above (2005 was 14.95; 2006 was 14.68, 2007 was 14.77).
It’s almost like Arctic sea ice extent in winter has almost no relationship with global temperatures!