Artic sea ice has melted to the second lowest level on record.
The National Snow and Ice Data Center says the amount of sea ice is down to 2.03 million square miles so far this year. The lowest point on record is 1.65 million square miles, but with three weeks left in the melt season, scientists say this year could break that record.
Some scientists are calling this a “tipping point” in global warming. NASA ice scientist Jay Zwally told the Associated Press it means that “climate warming is coming larger and faster than the models are predicting and nobody's really taken into account that change yet.” Zwally predicts that within five to ten years the Arctic could be free of sea ice in the summer.
Arctic ice always melts in summer, but lately more and more of the ice is melting and not refreezing in winter. This ice is important because it helps regulate global temperature and also serves as the primary habitat for polar bears.
Learn more about global warming .