evidence: Charctic Interactive Sea Ice Graphing Tool [...] Sea ice extent spatial comparison tool [...] Since 2007, this site has been a go-to source for blog-like insights, analysis, and data visualization tools that communicate how sea ice has been changing from year to year. We receive over two million page visits a year and our content is used by a wide range of users including journalists, the general public, academics, and scientists alike. Our analyses focus primarily on sea ice extent, which is a measurement of the area of ocean where there is at least some sea ice. In the Arctic, the annual minimum sea ice extent occurs in September and the annual sea ice maximum extent occurs in March. In the Antarctic, the minimum extent occurs in February and the maximum occurs in September. When compared with previous years and decadal averages, these periods when the annal extremes occur are particularly important indicators of how much ice is being lost over time.