Includes sea level rise; extreme weather; changes to ecosystems, plants and animals; melting ice and permafrost; ocean wamring; impacts to water resources, agriculture, public health and national security
In the mid-1980s, the winter sea ice pack in the Arctic was dominated by multi-year ice—ice that had survived at least one summer melt. Today, less than half of the sea ice at winter maximum has survived at least one summer.
Each summer, the seasonal unraveling of the Arctic’s blanket of ice exposes large areas of the ocean to solar heating. The smaller the ice extent, the larger the potential warming influence. Arctic sea ice extent in July 2011 was the lowest for that month in the satellite record.
When the winds are right, dust from the deserts of the U.S. Southwest blows onto the snow-capped Rocky Mountains. How do dirty snowfields contribute to the loss of more than 250 billion gallons of water in the Colorado River?
This report presents a comprehensive appraisal of Earth’s climate in 2009, and establishes the last decade as the warmest on record. Reduced extent of Arctic sea ice, glacier volume, and snow cover reflect the effects of rising global temperature.
In the summer of 2009, sea ice receded to its third-smallest area in recorded history. The reduced sea ice cover in the Arctic allowed an international group of scientists to study areas of the ocean that they have never been able to reach before.