NSIDC at AGU

Photograph of Ira Flatow speaking at AGU

Ira Flatow, host of National Public Radio’s Talk of the Nation: Science Friday, spoke at the AGU Presidential Forum, reminding us why we need to communicate science clearly and effectively. Credit: Laura Naranjo

If NSIDC scientists are busy all year long conducting their own research, how do they keep up with what their colleagues elsewhere are doing? They exchange flurries of emails and phone calls, of course, and collaborate on journal articles and projects. But once a year, many of them are in the same place at the same time for the same reason: to attend the fall meeting of the American Geophysical Union (AGU). Whether you’re interested in glaciers or geoids, sea ice or plate tectonics, Earth or Mars, AGU is right up your alley. Each year, more than 20,000 scientists, students, and educators converge in San Francisco for the weeklong meeting. Many of NSIDC’s staff participate in the meeting as well, presenting talks and posters detailing their latest research, data, and success stories. Continue reading

What caused last summer’s Greenland surface melt?

Data image showing extreme Greenland surface melt in summer 2012

These satellite-derived maps show the extent of surface melt over Greenland’s ice sheet during the summer of 2012. On July 8, about 40 percent of the ice sheet had melted at or near the surface. By July 12, nearly 97 percent of the ice sheet surface had melted. High pressure ridges that persisted over Greenland created a lingering heat dome that caused the extensive melt. Credit: Nicolo E. DiGirolamo, SSAI/NASA GSFC, and Jesse Allen, NASA Earth Observatory

During the summer of 2012, scientists noticed something unusual in Greenland. On July 8, about 40 percent of the Greenland Ice Sheet surface showed signs of melting. But a mere four days later, 97 percent of the surface was melting, an extent that was unprecedented in the satellite record.

Just how unprecedented was this event? Does it mean that the Greenland Ice Sheet is possibly on the way out, like summer sea ice in the Arctic? Continue reading

Arctic melt versus Antarctic freeze: Is Antarctica warming or not?

Photograph of a large tabular iceberg and sea ice near Antarctica

During the short austral summer, much of the sea ice surrounding Antarctica melts, often leaving only the large, tabular icebergs. Credit: NSIDC courtesy Andi Pfaffling

September 2012 was a record-setting month for both of Earth’s poles, but for different reasons: sea ice in the Arctic fell to a record low minimum extent after a summer of melting, while Antarctic sea ice froze to a record high extent during the South Pole winter. Is record Antarctic sea ice canceling out the losses in Arctic ice? And does the record in the south mean that Antarctica is not warming? Continue reading

Industry and ice

As the Arctic Ocean becomes increasingly ice-free, many countries are eager to tap into previously inaccessible northern resources. Energy companies seek drilling permits for oil and natural gas, and shipping companies hope to ply newly opened sea routes. Given the unpredictable nature of Arctic sea ice, some wonder if operating in the already inhospitable north will be an economically viable effort. Others believe that even if drilling or shipping is not currently viable, the Arctic is changing fast enough that industry in the Arctic is here to stay. Continue reading

Is stored heat causing Arctic sea ice to freeze later each year?

Graph showing Arctic sea ice minimum dates from 1979 through 2012, derived from satelite records

This graph shows the yearly trend toward later Arctic sea ice minimum dates, but also illustrates the wide variability from year to year. Credit: NSIDC

A reader recently asked if the date of the annual Arctic sea ice minimum is shifting later each year. And if so, is that shift a sign of heat being stored in the Arctic region?

According to the satellite record, Arctic sea ice generally melts to its minimum annual extent between the first and third week of September, after which ice begins freezing again. In recent decades, the Arctic has been gaining heat: Air, land, and ocean temperatures in the region have been slowly rising, and scientists have noted dramatic reductions in summer sea ice extent, as this heat causes more ice to melt away. But is this heat causing sea ice to form later each fall? Continue reading