News & Stories

Daily monitoring of surface melting in Antarctica resumes for the 2022-2023 season. Early melting through November has been limited to the region near the northern Larsen Ice Shelf, the Wilkins Ice Shelf, and an unusual melt event in Wilkes Land and Northern Victoria Land.

On December 10, 1972, the world of sea ice data changed forever. For the first time in history, as the Electrically Scanning Microwave Radiometer (ESMR) launched aboard the NASA Nimbus-5 satellite, scientists gained the ability to track changes in sea ice cover over the Polar Regions every day via passive microwave data. Today, they can piece together a half century’s worth of data from several instruments and satellite missions, including ESMR, to better understand how global warming is affecting Arctic and Antarctic sea ice. 

With satellite observations of sea ice extent stretching back to November 1978, NSIDC scientists can draw from more than 40 years of data to determine when an extent is above or below average or when it reaches a record high or low.

Freshly formed sea ice can be as thin as a few sheets of paper or as thick as a one-story house, depending on how long it has existed. Measuring sea ice thickness is harder than measuring how much sea ice covers the ocean surface but multiple approaches have been used.