Perennial Arctic Sea Ice Decline 1984 2016 (4 K)

Animation of Arctic sea ice between 1984 and 2016 showing the rapid decline in perennial sea ice. Perennial sea ice (or multiyear ice) is the portion of the sea ice that survives the summer melt season, may have a lifespan of nine years or more, and can grow up to four meters thick. Credit: NASA Scientific Visualization Studio