Ice Sheets

A 4,000-foot-high mountainside collapsed in Glacier Bay National Park in a massive landslide that spread debris for miles across the glacier below. It was a powerful reminder of the instability of the mountains in this part of Alaska and the risks that that instability creates. Scientists at Lamont discovered the landslide from its seismic signature and are studying it and another recent Alaska landslide and tsunami to improve understanding of landslide risks to this region and globally.

In southern Greenland in summer, rivers have been streaming off the ice sheet, pouring cold fresh water into the fjords. Attention has focused on the West Coast, where the majority of the meltwater has been entering the ocean in recent years, but a new study from Lamont's Marco Tedesco suggests that a greater risk to global climate may actually be coming from the East.

Humans have been burning fossil fuels for only about 150 years, yet that has started a cascade of profound changes that at their current pace will still be felt 10,000 years from now, a new study shows. Coastal areas, in particular, will experience the long-term effects as rising seas slowly redraw the world map as we know it and continue to rise long after emissions are brought down. Even in a scenario in which global temperatures warm to only about 2° Celsius above pre-industrial times, the analysis shows that several of the world’s coastal megacities will eventually be submerged.

Over the last century, glaciers in Greenland have been retreating quickly – at a rate at least twice as fast as any other time in the past 9,500 years, according to a new study. The study also provides new evidence for just how sensitive glaciers are to temperature changes, showing that they responded to abrupt and even short-lived cooling and warming in the past that lasted decades to centuries.

A snapshot of the changing climate of the West Antarctica Peninsula, where the impact of fast-rising temperatures provides clues about future ecosystem changes elsewhere.

A new study has found that powerful winds are removing massive amounts of snow from parts of Antarctica, potentially boosting estimates of how much the continent might contribute to sea level. Up to now, scientists had thought that most snow scoured from parts of the continent was simply redeposited elsewhere on the surface. However, the new study shows that in certain parts, called scour zones, some 90 percent—an estimated 80 billion tons per year—is instead being vaporized, and removed altogether. 

Summers on the Norwegian archipelago of Svalbard are now warmer than at any other time in the last 1,800 years, including during medieval times when parts of the northern hemisphere were as hot as, or hotter, than today, according to a new study in the journal Geology.

Stronger ocean currents beneath West Antarctica’s Pine Island Glacier Ice Shelf are eroding the ice from below, speeding the melting of the glacier as a whole, according to a new study in Nature Geoscience. A growing cavity beneath the ice shelf has allowed more warm water to melt the ice, the researchers say—a process that feeds back into the ongoing rise in global sea levels. The glacier is currently sliding into the sea at a clip of four kilometers (2.5 miles) a year, while its ice shelf is melting at about 80 cubic kilometers a year - 50 percent faster than it was in the early 1990s - the paper estimates.

Scientists still puzzle over how Earth emerged from its last ice age, an event that ushered in a warmer climate and the birth of human civilization. In the geological blink of an eye, ice sheets in the northern hemisphere began to collapse and warming spread quickly to the south. Most scientists say that the trigger...

North American Ice Sheet Dwindled Fast in Conditions Like Today's

In the face of warming climate, researchers have yet to agree on how much and how quickly melting of the Greenland ice sheet may contribute to sea level rise.

Lying beneath more than two miles of Antarctic ice, Lake Vostok may be the best-known and largest subglacial lake in the world, but it is not alone down there. Scientists have identified more than 145 other lakes trapped under the ice. Until now, however, none have approached Vostok’s size or depth.