Two of the major projects for this IPY will be the creation of permanent permafrost observations and an expansion of the International Tundra Experiment (ITEX), a model experiment that uses easily constructed greenhouses to artificially warm portions of the tundra. "We measure growth rate of certain tundra species and the vegetation composition and abundance. We've moved into ecosystem functions, carbon fluxes and nutrient fluxes," says Greg Henry, an ecologist at the University of British Columbia. "The next phases are a lot more soil biology, measuring changes below ground in fungal and microbial communities to get a handle on how they are responding to the warming."

The tundra experiment has been ongoing in some locations for more than 16 years but will be expanded throughout the world—even away from the poles to tundra in mountainous Australia and the Tibetan plateau. Meanwhile, permafrost observers the world over will take measurements in boreholes at least 30 meters (100 feet) deep—the depth where temperatures do not fluctuate during seasonal cycles—though some will stretch much deeper. "It will be a permanent network of sites for these observations, including the active layer, the thawing layer," Brown says. "It will be a great legacy of the IPY to say that we measured the permafrost."

ITEX will also help predict what may happen in the polar regions in the future. Satellite observations have already shown that the tundra is greening while ground crews report the increasing influx of shrubs and woodier cover. Since these plants are darker than the typical light tundra cover, they will warm their regions even more. "This albedo feedback could result in the same amount of warming as a doubling of [carbon dioxide]," Henry says. "That's a major impact."

Undiscovered Mountains and the Legacy of Ice

There are few places on Earth that remain unmapped; Antarctica hosts a mountain range that shouldn't be there and has never been seen. "They are the size of the Alps and the birthplace of the Antarctic ice sheet," says geophysicist Robin Bell of the Lamont-Doherty Earth Observatory in New York City. "There aren't supposed to be mountains in the middle of stable continents."

Mapping this buried range will help scientists understand how glaciers formed in Antarctica as well as how today's ice sheets interact with the ground below. Scientists have already discovered enormous lakes deep under the ice, a result not predicted in any model.

Without an understanding of how ice interacts with the ground, models cannot accurately forecast how the ice will behave as conditions change. Given the potentially catastrophic contribution of such land ice to global sea level rise, a better understanding of ice dynamics is one of the key goals of the IPY. And it all begins in unexplored mountains. "At the last IGY, we thought the Antarctic sheet was a giant pillow," Bell says. "We now have a very different picture." And that picture will change yet again.

Peoples of the Poles

There are no greater guides to Arctic ice than the Inuit, who have studied its contours for generations. Known as siku, sea ice guides hunters on their annual quest for sustenance, providing access to hunting grounds and shelter from storms. The Sea Ice Knowledge and Use (SIKU) project aims to record some of this information as the sea ice the hunters have known changes before their eyes. "The sea ice becomes almost an extension of their land," says Claudio Aporta, an anthropologist at Carleton University in Ottawa. "Their records of those camps have been there year after year for at least 200 years of written history."

By mapping current conditions with the help of Inuit hunters as well as by compiling maps of the past based on oral histories and the memories of elders, the researchers hope to capture the Inuit's special understanding of sea ice. By combining that with modern tools such as the Global Positioning System and remote sensing, a deeper understanding of the fundamental nature of the ice can be gained as it changes. And maybe the lessons learned can help the Inuit in return. "The patterns of sea ice freezing and breaking up is changing," Aporta says. "They have to adapt."

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