Wilkins Ice Shelf Continues Break-up, Even During Winter

Satellite images reveal the Wilkins Ice Shelf in Antarctica has experienced further break-up with an area of about 160 square kilometers breaking off during May 30 -31, 2008. ESA’s Envisat satellite captured the event. This is the first ever-documented episode to occur during the Antarctic winter. The animation here, comprised of images acquired by Envisat’s Advanced Synthetic Aperture Radar (ASAR) between May 30 and June 9, highlights the rapidly dwindling strip of ice that is protecting thousands of kilometers of the ice shelf from further break-up.

Wilkins Ice Shelf, a broad plate of floating ice south of South America on the Antarctic Peninsula, is connected to two islands, Charcot and Latady. In February 2008, an area of about 400 square km broke off from the ice shelf, narrowing the connection down to a 6 km strip; this latest event in May has further reduced the strip to just 2.7 km.

According to Dr. Matthias Braun from the Center for Remote Sensing of Land Surfaces, Bonn University, and Dr. Angelika Humbert from the Institute of Geophysics, Münster University, who have been investigating the dynamics of Wilkins Ice Shelf for months, this break-up has not yet finished.

“The remaining plate has an arched fracture at its narrowest position, making it very likely that the connection will break completely in the coming days,” Braun and Humbert said.
Long-term satellite monitoring over Antarctica is important because it provides authoritative evidence of trends and allows scientists to make predictions. Ice shelves on the Antarctic Peninsula are important indicators for on-going climate change because they are sandwiched by extraordinarily raising surface air temperatures and a warming ocean.

The Antarctic Peninsula has experienced extraordinary warming in the past 50 years of 2.5°C, Braun and Humbert explained. In the past 20 years, seven ice shelves along the peninsula have retreated or disintegrated, including the most spectacular break-up of the Larsen B Ice Shelf in 2002, which Envisat captured within days of its launch.

News Source: ESA