The National Snow and Ice Data Center (NSIDC), in Boulder, CO, updates a webpage each day, showing the measured sea ice extent for both the Arctic and Antarctic polar regions. The data is presented via a user-customizable chart, called the ‘Charctic Interactive Sea Ice Graph’. Here is a screen-cap of a recent chart, with additional content added by aiREFORM.com:
This chart shows daily Arctic sea ice extent for selected years (2006, 2007, 2011, 2012, 2013, 2015 and 2016) for the calendar window from approximately January 15th through March 26th each year. The color-codes for the lines representing each year are noted in the index; the heavy black line (highest plot) represents an average for all years 1981-2010. The gray background band represents a range of +/-2 standard deviations for the 1981-2010 dataset.
For each calendar year, there is a date at which the peak Arctic sea ice extent is reached. Following that date, sea ice extent declines until reaching an annual cyclical bottom, typically in mid- to late- September. Vertical red lines have been added to help see the dates of peak sea ice extent. The ‘average’ date for peak ice, as suggested by the 1981-2010 average plot, is March 13th. Note that the peak for 2015 was the earliest on record: February 25th. Now, for this year, as of February 17th, the Arctic sea ice extent is 14.203 square kilometers. We are at an all-time low record, and nearly 2% below last year, when we had 14.469 square kilometers extent.
So far this year, the sea ice extent has set new records for three different time periods: January 3-9, February 2-6, and for the past week (starting on February 11). This data offers yet one more indicator suggesting that we are imposing very rapid and very significant warming onto our planet, with a consequence of accelerated polar ice melting.