The continued significant reduction in the area covered by the summer sea ice is a dramatic illustration of the pronounced impact increased global temperatures are having on the Arctic regions. There has also been a significant reduction in the relative amount of older, thicker ice. Satellite-based passive microwave images of the sea ice cover have provided a reliable tool for continuously monitoring changes in the Arctic ice cover since 1979. The ice parameters derived from satellite ice concentration data that are most relevant to climate change studies are sea ice extent and ice area. This visualization shows the annual September minimum sea ice area in the background and a graph of the ice area values foreground. The ice area provides the total area actually covered by sea ice which is useful for estimating the total volume and therefore mass, given the average ice thickness. For more information about these ice datasets, see The Journal of Geophysical Research VOL. 113, C02S07, doi:10.1029/2007JC004257, 2008
This visualization shows the annual Arctic sea ice minimum from 1979 to 2011. A graph is overlaid that shows the area in million square kilometers for each year's minimum day. The '1979','2007', and '2011' data points are highlighted on the graph.
GCMD keywords can be found on the Internet with the following citation:
Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 184.108.40.206.0