In 2012, sea ice melted to a record-breaking minimum extent. At the end of the summer melt season, ice covered only about half of the average area it did from 1979–2000.

Arctic sea ice extent fell to 1.58 million square miles on August 26, 2012. This was 27,000 square miles smaller than the previous record low of 1.61 million square miles set in 2007.

In September 2011, Arctic sea ice reached its second-lowest minimum extent in the satellite record.

NOAA scientists have documented a new impact of the increasingly thin blanket of Arctic sea ice: gases escaping from the thinner ice in spring are affecting air chemistry, reducing ground-level ozone, and likely increasing mercury contamination.

Jackie Richter-Menge describes the "Arctic amplification" phenomenon: how the loss of Arctic sea ice leads to further warming.

Satellite observations show that as the Arctic tundra has grown warmer in the past three decades, it has also grown “greener.”

In the Arctic, an ocean is surrounded by continents, while Antarctica is continent surrounded by oceans. These differences in the arrangement of land and water contribute to differences in each polar region’s climate, oceanic and atmospheric circulation patterns, and seasonal and long-term sea ice patterns.