Most Current Ice Age The Polar Regions have widely been thought of as the "Canary in the Mine" for the global climate system. The ice formation and its extent is very sensitive to changes in temperature and weather patterns.


WHY ICE AGE:
1: Generally the longer the ice has survived, the thicker it is. If you look at the monthly animations, you will noticed a dramatic decline in the overall age of the ice. Also, if you look at the summer animations, you will also notice the areal extent of the ice has declined. Together these show significant changes just in the last 28 years, especially in the last 5 to 10 years.
2. Because the ice is thinner, there is also the possibility that the ice will melt sooner, further decreasing the extent of the ice during the summer. Also, because there is less ice and more open water showing, the top layer of the water can be more warmed by the sun during the summer, delaying the formation of new ice in the fall. This is what is called positive feedback, where loss of ice increases the possibility of more loss of ice.
Colorbar shows age of ice:
light blue is Open Water OW -- red is ice 5 years or older
Lower right shows week of year and the year

View Animation for Current Ice Year (Week of Beginning Fall Freeze Up to the Present)

Animations for Each Month for 28 years (closest week to beginning of month)
January February March April May June July August September October November December

Method: The ice age data is generated using a fairly simple model using ice motion vectors and ice extent data on a 12.5 km grid and run at weekly steps. At each step previous ice is moved on the grid using the motion vectors and ice is added or eliminated based on the ice extent data. The ice is "aged" one year the week after the date showing the minimum ice extent.
Contact:
Chuck Fowler (cfowler@colorado.edu)
Jim Maslanik ( jimm@colorado.edu) 		Funding and Support: NASA Cryospheric Sciences Program and NOAA