The seasonal maximum was recorded on February 25, at 5.61 million square miles (14.54 million square kilometers), being one of the earliest too since average maximums are recorded in March or April and minimum extent is recorded in September.
The past decades have seen a downward trend in Arctic sea ice extent during both the growing and melting season, though the decline is steeper in the latter.
This year's maximum was reached 15 days earlier than the 1981 to 2010 average date of March 12, according to NSIDC. Only in 1996 did it occur earlier, on Feb. 24.