From record-low Arctic sea ice to the highest global sea level of the modern record, the 2012 State of the Climate report provides a complete rundown on the state of Earth's climate and how it is changing.
The extent of snow-covered ground in the Northern Hemisphere at the end of the cold season (June) hit a record low. Annual average snow cover extent has not exceeded the long-term average even once since 2003. Between 1979 and 2011, the snow cover in June is declining even faster than the end-of-summer Arctic sea ice extent.
Since 1976, every year has been warmer than the long-term average, and 2012 continued the trend: the global surface temperature ranked among the top 10 warmest years on record.
Earth's atmosphere includes billions and billions of gallons of evaporated water: in fact, water vapor is Earth's most abundant greenhouse gas.