Arctic

About 3 million years ago, evergreen forests — not tundra — carpeted the Arctic, Greenland was green, and sea ice only formed for a few months in the winter, if it formed at all, according to analysis of sediment pulled from a Russian lake.

“Where we are going is into this warmer world,” Julie Brigham-Grette, a geologist at the University of Massachusetts Amherst, told NBC News.

At the time — the Pliocene — concentrations of the greenhouse gas carbon dioxide were around 400 parts per million, the same as they are today. But Arctic temperatures were about 14.4 degrees Fahrenheit (8 degrees Celsius) warmer than today, explained Brigham-Grette, who led the analysis.

By the middle of this century, thanks to climate change, anyone with a light icebreaker can spend their Septembers going anywhere they want in the Arctic Ocean, including straight over the North Pole, according to a new study.

Ordinary vessels, which account for more than 99 percent of shipping traffic, could easily navigate the Northern Sea Route along the Russian coastline and, in some years, even find a route through the fabled Northwest Passage.

“That’s kind of crazy and, frankly, a little bit worrisome,” Laurence C. Smith, a geographer and sea ice expert at the University of California, Los Angeles, told NBC News. “It is not like these will be open blue seas and safe or open year round.”

A helium-filled, doughnut-shaped blimp with a wind turbine for its filling may soon be the go-to power source for remote villages and industrial operations.

“Definitely one of our use cases is providing a consistent, reliable source of power in remote communities and island nations,” Ben Glass, who invented the turbine at MIT, told me on Thursday.

Scientists have long used satellite imagery to illustrate the shrinking extent of the Arctic sea ice. Now they’ve got satellite data that will provide regular updates on whether the ice is getting thinner as well.

The first ice thickness map from the European Space Agency’s CryoSat spacecraft was released Tuesday at an air show in Paris. It was compiled with data collected in January and February.

The map shows, for example, the ice is thickest near the North Pole and off the coasts of Greenland and northeastern Canada. It thins as it stretches out towards Alaska and Russia.

A decade ago, global climate change was largely considered a problem for the distant future. But it seems that future has come sooner than predicted.

One of the most remarkable, and alarming, environmental changes to occur over the last decade is the melting of Antarctic ice sheets and the recession of Arctic glaciers at speeds much faster than climate change models had predicted, according to environment experts.

The Arctic Ocean could be largely ice free in summer within a decade, scientists announced today—the latest in a stream of wildly varying predictions.

This past spring scientists had taken measurements along a 280-mile (450-kilometer) route across the northern part of the Beaufort Sea (map). Most of the ice, they found, was young and thin.

From “shooting stars” to the growth of dead zones in the Gulf of Mexico, there are several science-related things that occur in the summer. Check out ten.