NASA finds Arctic sea ice abundance in 2023 will be sixth-worst on record

Satellite data shows that Arctic sea ice may have reached its annual minimum extent on September 19, 2023. Arctic sea ice may reach its annual minimum extent on September 19, 2023, making it the sixth-lowest in satellite records, according to researchers at NASA and the National Snow and Ice Data Center (NSIDC).

This map is based on satellite data and shows sea ice abundance on September 19, 2023. This may be the smallest annual range this year.

Sea Ice Meaning and Measurement

Scientists track seasonal and annual fluctuations in sea ice because it shapes Earth's polar ecosystems and plays an important role in global climate. NSIDC and NASA researchers use satellites to measure the melting and refreezing processes of sea ice. They track sea ice extent, which is the total area of ​​the ocean covered by at least 15 percent ice. The map at the top of this page shows sea ice extent on September 19, 2023.

This map tracks daily Arctic sea ice extent, highlighting September 19, 2023, the year's likely annual minimum extent.

From March to September 2023, the Arctic ice cover shrank from its peak of 5.64 million square miles (14.62 million square kilometers) to 1.63 million square miles (4.23 million square kilometers). This is approximately 770,000 square miles (1.99 million square kilometers) below the 1981-2010 average minimum of 2.4 million square miles (6.22 million square kilometers). Enough sea ice has been lost to cover the entire continental United States.

Changing Arctic patterns

This year, scientists found significantly less ice in the Arctic Northwest Passage. "It's more open than it used to be," said Walter Meier, a sea ice scientist at NSIDC. "There also seems to be more loose, less dense ice there - even in the Arctic - where in the past those areas were very compact, solid ice throughout the summer. That's been happening more and more frequently in recent years."

These changes are a fundamental, decades-long response to warming temperatures, Meyer said. Not only has Arctic sea ice been shrinking since satellite records began in 1979, it's also getting younger. The spring thaw starts earlier and the fall freezes later and later, resulting in longer and longer thaw seasons. Research shows that the average freeze period across the Arctic Ocean is delayed by one week per decade, or one month later than in 1979.