Arctic Ice Cover at Near-Record Low

Findings from the National Snow and Ice Data Center at the University of Colorado show maximum ice cover in the Arctic Ocean reached one of its lowest levels ever this winter, providing further evidence for climate change. Data collected so far suggests Arctic sea ice reached its maximum extent on March 7th of this year, before it began shrinking as temperatures warmed. This is part of a natural annual cycle, in which sea ice in the Arctic builds up over the winter, reaches maximum size sometime in February or March, and then gradually retreats over the spring and summer.

What’s been different in recent years is that ice cover throughout the course of the cycle has been growing less and less on average. This year’s maximum ice cover tied with 2006 for the smallest ever recorded.

This is consistent with the best projects of how rising levels of carbon emissions will affect the globe, and suggests climate change is occurring just as climate scientists have long predicted it would. As the Arctic melts, the reverberations will be felt all over the world, sometimes in counterintuitive ways. For example, climate scientists believe the exceptionally harsh winters experienced these past few years in the eastern United States are due partly to shifting wind patterns caused by a warming Arctic. Meanwhile melting ice cover contributes to rising sea levels.

There will always be year to year fluctuations in weather—in the Arctic just like everywhere else—and not every year will set a new record for warm temperatures or reduced ice cover. However the overall pattern uncovered by scientists clearly shows sea ice is shrinking. The Snow and Ice Data Center has compared records going back to 1979 that show a shrinking trend in both winter and summer ice cover. Data from the National Oceanic and Atmospheric Administration confirm those findings.

Last year in September, the month that marks the end of the melt season when Arctic ice cover is smallest, the Snow and Ice Data Center reported summer ice reached its third smallest extent ever. Only three times since satellite record keeping began has ice cover reached a low point less than 1.93 million miles. One of those times was in 2010, and all three have occurred in the last four years. Scientists predict this trend will continue, and by 2030 the Arctic could be completely ice-free in late summer.

In the last thirty years satellite records and other technological advances have allowed scientists to monitor ice levels more accurately than ever before. Like the reams of temperature data collected from throughout the world by climate research centers, sea ice records allow us to track the effects of climate change and watch as global warming takes place. However the information is of little practical value if major economies don’t take it as a warning to reduce their carbon emissions. The science of global warming and its implications for life on Earth is clear. Now world nations must act to minimize the damage.

Photo credit: US Geologic Survey