33 Years of Arctic Sea Ice Extent

Working from a spreadsheet of Arctic sea ice measurements from the National Snow and Ice Data Center (NSIDC), I wrote Processing code to generate a line graph in the round for each of the 33 years of collected data. It was a happy coincidence that I was 33 years old at the time.

The maximum extent of Arctic sea ice is typically 15 square kilometers (twice the land area of the continental US). The seasonal melt for each year peaks in mid-September, usually shrinking the ice by half. At the peak melt in 2012 the ice extent was 3.3 million square kilometers, the lowest ever recorded. During July of 2012, cargo ships were able to transit the Northern Sea Route, a trip that was previously only possible in September.

The drawings were executed using digital embroidery, where each stitch of the average and yearly information corresponds to an actual data point. Each circle is identical except for the red line showing that year's data. The silver area denotes the acceptable range of sea ice (+/- 2 standard deviations), and the blue line within the silver is the average. The calendar starts at the top and moves clockwise, with each radiating line indicating a month. Every concentric circle indicates one million square kilometers of sea containing at least 15% ice.