Tweet Image Credit: NASA/Goddard Space Flight Center Scientific Visualization Studio One of the most striking changes that has taken place in the Arctic since the start of satellite monitoring in 1979 is the rapid decline of the perennial sea ice cover. This ice is the sea ice that survives the summer melt season, and is typically the thickest part of the sea ice cover, sometimes spanning several years. Sea ice extent has declined as the globe has warmed, but the ice cover has thinned as well. Thinner sea ice melts more easily, and as multiyear sea ice is lost, Arctic sea ice has declined more rapidly. This NASA visualization shows the perennial Arctic sea ice cover from 1980 to 2012. The grey disk at the North Pole indicates the region where no satellite data is collected. A graph overlay shows the area’s size measured in million square kilometers for each year. The ’1980′, ’2008,’ and ’2012′ data points are highlighted on the graph. And here’s the video: Original post by ClimateCentral.org SUBSCRIBE TO NEWSLETTER Thank you, your sign-up request was successful! Please check your e-mail inbox. Given email address is already subscribed, thank you! Please provide a valid email address. Oops. Something went wrong. Please try again later.