1. Measuring Arctic and Antarctic Ice
Morton M. Sternheim
June, 2011

2. Arctic Ice Caps – 31 year change Sept. 1979 Sept. 2010

3. Arctic Ice Cap Is Shrinking
Climate change is greatest in polar regions
Northwest and Northeast Arctic passages opening
Monthly Arctic and Antarctic NOAA images online from November 1978
Students can measure areas with ADI Mask Colors
Seasonal increase and decrease in area
Area changes over the years
September extent decreased over 30%
Similarities and differences between Arctic, Antarctic
Have each group do a few images, plot joint graph

4. Seasonal Variation March 2010 Sept. 2010

5. Measuring The Ice Area Steps
Open the image
Select Known Pixel Size and type in 31 km.
Click on the Mask Colors button
Click, drag a small rectangle in ice covered area.
We want to find the number of pixels matching this area. For speed, uncheck the green and blue boxes. Click on Apply Mask-TEST 1; wait a while
The number of masked pixels and the corresponding area will appear on the lower right.

7. Arctic and Antarctic Ice Images
ftp://sidads.colorado.edu/DATASETS/NOAA/G02135
Individual files, sorted by month; ice areas noted
Zip files with and without areas
March, September image zip files for all years
Monthly images for 2010