Arctic losing 77,800 square kilometres sea ice every year as Earth warms

The loss of sea ice has been occurring at a rate of about 77,800 square kilometers per year, according to NSIDC data. This decline is not just in extent but also in ice quality.

In Short

• This year's minimum extent is 1.94 million square kilometers below the 1981-2010
• The 2024 minimum aligns with the ongoing downward trend
• This thinning ice is more susceptible to melting

Arctic sea ice reached its annual minimum extent on September 11, 2024, marking another year of significant ice loss in the Northern Hemisphere.

According to researchers at Nasa and the National Snow and Ice Data Center (NSIDC), this year's minimum extent was 4.28 million square kilometers, continuing the decades-long trend of shrinking and thinning ice cover in the Arctic Ocean.

This year's minimum extent is approximately 1.94 million square kilometers below the 1981-2010 end-of-summer average, covering an area larger than Alaska.

While not setting a new record low, the 2024 minimum aligns with the ongoing downward trend observed since satellite monitoring began in the late 1970s.

The loss of sea ice has been occurring at a rate of about 77,800 square kilometers per year, according to NSIDC data. This decline is not just in extent but also in ice quality.

Nathan Kurtz, lab chief of Nasa's Cryospheric Sciences Laboratory, noted that the majority of Arctic sea ice is now thinner, first-year ice, which is less resilient to warmer temperatures.

Measurements from Nasa satellites have revealed that central Arctic sea ice thickness has decreased from 2.7 meters in 1980 to around 1.3 meters today.

This thinning ice is more susceptible to melting and breaking up during the summer months.

The situation in the Antarctic is equally concerning. Sea ice extent around Antarctica is approaching record lows during a time when it should be expanding.

The current extent is just over 16.96 million square kilometers, significantly below the 1981-2010 average maximum of 18.71 million square kilometers.

This ice loss creates a feedback loop known as ice-albedo feedback, where less ice leads to more heat absorption by the ocean, further delaying ice growth.

The Arctic has experienced warming at about four times the global average rate, highlighting the region's sensitivity to climate change.