Antarctica is Disappearing

Over a 35-day period from January 31 to March 7, 2002, Antarctica's Larsen B ice shelf lost a total of about 1,255 square miles (3,250 square kilometers), one of the largest shelf retreats ever recorded. This image, captured by NASA's MODIS satellite sensor on February 23, shows the shelf mid-disintegration, spewing a cloud of icebergs adrift in the Weddell Sea. In December 2007, a team of National Geographic explorers will begin a five-week expedition across the continent's Larsen ice shelf to study how global warming is changing the topography of Antarctica.

A stark white lobe of a glacier advances across Antarctica's dry valleys region, so called because of its scarcity of snow. Earth's fifth-largest continent contains more than two-thirds of the world's fresh water in the form of ice, yet some areas receive less than two inches (five centimeters) of precipitation a year.

Global warming is forcing ice shelves to calve, producing icebergs like this monolith jutting into the waters of the Antarctic Peninsula. National Geographic's Larsen Ice Shelf Expedition team will examine calving shelves and the bergs they spawn, determining how shelves fragment and how diminishing ice mass affects the world's oceans and climate.

A leopard seal plunges through Antarctic waters. Swift and stealthy, adult leopard seals tend to be solitary creatures, hunting alone at the fringes of pack ice. Finding a mate can be challenging given their isolation, but seals attract one another by singing—females to announce their readiness to a mate, males to serenade potential mates.

Icebergs drift across Antarctica's Neumeyer Channel. The Larsen Ice Shelf Expedition team predicts melting Antarctic shelves and bergs will raise sea levels around the world, flooding hundreds of thousands of square miles and displacing tens of millions of people. The team will collect evidence from their expedition to better understand how global warming is changing the continent and how we can prepare ourselves for its effects.