Scientists seek answers to berg breakup riddles
This is the edge of giant iceberg B15a before it broke into four parts in 2005.
JB: This is Earth and Sky. In recent months, scientists monitored the breakup of the world’s biggest iceberg.
DB: The iceberg, called B-15, formed in year 2000 when it split off the Ross ice shelf in Antarctica. And in November of 2005, satellite images captured its fracture into four large shards over just an 8-hour period. Ted Scambos is lead scientist at the National Snow and Ice Data Center in Boulder, Colorado. We asked him whether the creation of the iceberg was part of a natural cycle, or due to global warming.
Ted Scambos: You’re right in that the cycle for most of the ice shelves is that every 30 to 50 years, they’ll calve off, either one very large iceberg or several very close together . . . We think right now that that’s just a standard process that goes on, and that global change really hasn’t had an effect on that.
JB: Scambos doesn’t believe global warming created the large iceberg labeled B-15 because there’s been no measured increase in the ocean temperature in that area. Still, in 2005, scientists did measure an increase of one degree Celsius in the ocean waters west of the Antarctic peninsula, in contrast with temperatures there in the 1960s. And that warming is thought to be part of the ongoing measured warming around the globe. It’s thought that continued warming could threaten the ability of marine species such as whales and penguins to live near the Antarctic peninsula. Thanks today to NOAA, the National Oceanic and Atmospheric Administration. We’re Block and Byrd for Earth and Sky.
Additional Teacher Resources
NASA Earth Observatory: Iceberg B-15, Ross Ice Shelf, Antarctica
Iceberg B-15 broke from the Ross Ice Shelf in Antarctica in late March. Among the largest ever observed, the new iceberg is approximately 170 miles long x 25 miles wide. Its 4,250 square-mile area is nearly as large as the state of Connecticut.
NASA: Huge Antarctic Iceberg Makes a Big Splash on Sea Life
NASA satellites observed the calving, or breaking off, of one of the largest icebergs ever recorded, named “C-19.” C-19 separated from the western face of the Ross Ice Shelf in Antarctica in May 2002, splashed into the Ross Sea, and virtually eliminated a valuable food source for marine life.
