Arctic ice driver incident report series#

However, perennial-year round-sea ice at the North Pole first occurred 14-18 million years ago. It likely first formed about 47 million years ago. Sea ice in the Arctic Ocean has a history much longer than the last 2,000 years. Meanwhile, proxy records show that the current warming trend in surface air temperatures has not been observed in the Arctic over at least the last 2,000 years. Since 1900, waters that enter the Arctic Ocean through the Fram Strait have increased by 2 degrees Celsius (4 degrees Fahrenheit). The minimum sea ice extent, which occurs each summer, is influenced by the atmospheric circulation, air temperature, and variations in the amount of warm water that flows into the Arctic. And just as importantly, it is beyond the range of natural variability, implying a human component to the drastic decrease observed in the records. These records show that while there have been several periods over the past 1,450 years when sea ice extents expanded and contracted, the decrease during the modern era is unrivaled. Scientists use climate proxies like sediment/ice cores, tree rings, and fossilized shells of ocean creatures to extend the sea ice extent records back in time.

Arctic ice driver incident report series#

This time series shows the Arctic sea ice extent in millions of square kilometers over the past roughly 1,500 years. Reconstructions such as this one extend our knowledge into the distant past, and they provide context for the extraordinary increases in ocean temperature and decreases in ice extent that have occurred in recent times. In the 2017 issue of NOAA’s Arctic Report Card, scientists report on a body of paleoclimate research that shows that the extent and rate of sea ice decline in the Arctic is unprecedented over at least the past 1,500 years.