NSIDC Sea Ice Extent Monthly median sea ice extents for the period 1981-2010. Fetterer, F., K. Knowles, W. Meier, M. Savoie, and A. K. Windnagel. 2016, updated daily. Sea Ice Index, Version 2. [Indicate subset used]. Boulder, Colorado USA. NSIDC: National Snow and Ice Data Center. doi: http://dx.doi.org/10.7265/N5736NV7. [Date Accessed]. http://nsidc.org/data/g02135 Download: 24 July 2017 Downloaded and merged shapefiles from ftp://sidads.colorado.edu/DATASETS/NOAA/G02135/south/monthly/shapefiles/shp_median/ Editor Sea Ice Takeshi Tamura tamura.takeshi@nipr.ac.jp Author Florence Fetterer fetterer@nsidc.org