News & Events

Larsen B Ice Shelf disintegration of 2002: The conspiracy theory

Monday, September 22, 2014, 12:00PM - 1:00PM

Speaker

Ted Scambos

NSIDC/CIRES

Location:

ARC room 620

An iconic event in the response of polar ice sheets to climate change, the Larsen B Ice Shelf disintegration event of February-March, 2002 has long been attributed to climate warming, surface melting, and hydrofracture. But in looking closer, we can identify a number of collaborators in the geophysical cabal that led to the destruction.

Early Landsat and other images show that the shelf margins were relatively stable in the 1970s and early 1980s, and then began to evolve beginning in the mid to late 1980s. This coincides with a period of reduced sea ice cover (shorter sea ice duration) off the eastern ice shelf front. Moreover, increased westerly winds—the squeaky wheel, implicated in similar crimes throughout the continent—led to increasing frequency of Chinook wind events. These "snow eater" winds, in those spring or summer seasons where they are prevalent, are responsible for the melting events (and ablation) that led to a nearly solid ice cover on the Larsen B capable of supporting melt ponds upon its surface. With these ice-blue watery bullets fully loaded as January 2002 came to a close, it required the merest shudder to trigger a massive destruction. That shudder may have come from a gang of rogues, rogue waves, let into a neighborhood that they rarely visit by the absence of sea ice cover. In the ensuing years, the glacier cohorts of the former Larsen B continued to attempt to fill the hole left behind by this tragic and complex conspiracy.

Audience

Free and open to the public.