Arctic sea ice extent appears to have reached its seasonal minimum in the past day or two. The National Snow and Ice Data Center has not yet "called" the minimum but indicated a few days ago that the minimum extent would be slightly lower than last year. However, the Danish Meteorological Institute graphic suggests that the ice extent is very slightly higher than last year (see below). Regardless, this year's ice extent has followed a similar path to 2013 throughout the melt season.
It's worth noting that the CFSv2 computer model forecast of significantly increased ice extent this year was flat-out wrong. We discussed the forecast here and here. Given the magnitude of the anomaly in the forecast, this is quite a bust.
Here are some other figures to document this year's ice cover at seasonal minimum, courtesy of the University of Illinois and NSIDC.
I believe thickness in standardsized locations or estimates of an ice volume time series should be also considered if overall annual changes in Arctic Sea ice are discussed.
ReplyDeleteFor example here's some modeling background from PIOMAS:
http://psc.apl.washington.edu/wordpress/research/projects/arctic-sea-ice-volume-anomaly/
Gary
Gary, thanks - I agree, although as I understand it thickness and volume are known with less certainty. It appears the estimated ice volume is higher than last year, which is interesting, so I'll plan to post something about this in early October, when the September analysis is available.
DeleteHi Richard. Yes I assume the satellites provide better estimates of overall ice coverage than depth, volume, or as they term it, density.
DeleteHere's some additional links that describe studies of Arctic Sea ice. It's critical to ignore the politics and personal opinions offered in mass media and some blogs, and focus on credible data.
http://arctic.atmos.uiuc.edu
http://www.arctic.noaa.gov/data.html
Gary
http://science.nasa.gov/science-news/science-at-nasa/2014/22sep_seaice/
Delete2014 NASA sea ice minimum and visual image over time.
Gary
Thanks Gary.
Delete