mit | Each winter, wide swaths of the Arctic Ocean freeze to form sheets of
sea ice that spread over millions of square miles. This ice acts as a
massive sun visor for the Earth, reflecting solar radiation and
shielding the planet from excessive warming.
The Arctic ice
cover reaches its peak each year in mid-March, before shrinking with
warmer spring temperatures. But over the last three decades, this winter
ice cap has shrunk: Its annual maximum reached record lows, according
to satellite observations, in 2007 and again in 2011.
Understanding
the processes that drive sea-ice formation and advancement can help
scientists predict the future extent of Arctic ice coverage — an
essential factor in detecting climate fluctuations and change. But
existing models vary in their predictions for how sea ice will evolve.
Now
researchers at MIT have developed a new method for optimally combining
models and observations to accurately simulate the seasonal extent of
Arctic sea ice and the ocean circulation beneath. The team applied its
synthesis method to produce a simulation of the Labrador Sea, off the
southern coast of Greenland, that matched actual satellite and
ship-based observations in the area.
