Friday, June 17, 2011

Arctic Sea Ice Volume Anomaly and Trend from PIOMAS

Daily Ice Volume 

Arctic Sea Ice Volume Anomaly

Sea Ice Volume is calculated using the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS, Zhang and Rothrock, 2003) developed at APL/PSC.  Anomalies for each day are calculated relative to the average over the 1979 -2010 period for that day of the year to remove the annual cycle. The model mean annual cycle of sea ice volume over this period ranges from 28,700 km3 in April to 12,300 kmin September.  The blue line represents the trend calculated from January 1 1979 to the most recent date indicated on the figure.  Monthly averaged ice volume for May 2011 was 20,200 km3. This value is 28% lower than the mean over this period, 37% lower than the maximum in 1979, and 2.5 standard deviations below the trend. Shaded areas represent one and two standard deviations of the residuals of the anomaly from the trend. Updates will be generated at approximately one-month intervals.
Arctic sea ice volume anomaly from PIOMAS updated once a month. Daily Sea Ice volume anomalies for each day are computed relative to the 1979 to 2010 average for that day of the year. The trend for the period 1979- present  is shown in blue. Shaded areas show one and two standard deviations from the trend. Error bars indicate the uncertainty of the  monthly anomaly plotted once per year.
November Ice Volume Anomaly 
Total Arctic sea ice volume from PIOMAS showing the volume of the mean annual cycle, the current year,  and 2007 (the year of minimum sea ice extent in September). Shaded areas indicate one and two standard deviations from the mean.

2 comments:

  1. A must see interview with Thomas Friedman and Paul Gilding:
    http://www.abc.net.au/reslib/201106/r785916_6801350.asx

    ReplyDelete
  2. thanks so much for the link, just posted it!

    ReplyDelete