20.6: The Cryosphere and Climate Change
The Cryosphere and Climate Change
The extent of sea ice Links to an external site. coverage on the North and South Polar ice sheets is easy to assess from satellite images and is measured as the size of the ice sheet in million square kilometers (Figure 20.9). Sea ice extent is not a perfect indicator of global climate change, but it is easy to understand that a warming of the Earth is likely to cause a decrease in the amount of ice at the poles and thus a decrease in the sea ice extent, while a cooling event will cause an increase in ice production.
Figure 20.9: The Arctic Ocean is covered by a dynamic layer of sea ice that grows each winter and shrinks each summer, reaching its yearly minimum size each fall. (CC-BY 2.0; NASA/Goddard Space Flight Center Scientific Visualization Studio Links to an external site.)