Study finds human and natural Arctic warming
(Credit: US CIA's World Factbook via Wikipedia.)
A new study finds that both humans and nature are contributing to the dramatic melting of Arctic ice.
Oceanographer James Overland told Earth & Sky that scientists have long understood natural cycles can combine with human causes to raise global temperatures. His study was aimed at finding out how much warming is caused by humans, and how much comes from nature.
James Overland: Basically, it’s the combination of the two together that’s so unusual and so important.
Nature has contributed to the warming. For example, a natural cycle of winds blowing toward the North Pole have carried warm air and clouds that trap heat. That unusual weather pattern has been observed by scientists for over the past 20 years. But nature can’t account for all the warming in the Arctic.
James Overland: We probably would not have reached these effects unless we had this background global warming. It’s very difficult to go back to the way we were 20 years ago.
Together, nature and Earth’s large human population have raised Arctic temperatures and reduced sea ice cover.
James Overland: You have to take the long term global warming trend and then add the natural variability on top of it, and combined they send you to a new climate state that we haven’t seen before.
That was oceanographer James Overland. Our thanks today to NOAA, the National Oceanic and Atmospheric Administration.
Additional Teacher Resources
NOAA: Arctic Theme Page
This NOAA webpage provides information on the Arctic including North Pole web cam images and animation, facts about the arctic, and links to scientific data, education materials, and more.
Smithsonian: Arctic – For Educators
This Smithsonian webpage provides a variety of lesson plans designed to teach students in grades 4-8 about the Arctic and climate change. The activities explore changes in the Arctic climate that are being observed by both polar scientists and polar residents.
