Although you might have a hard time convincing residents of the eastern United States, Scandinavia, and Russia (outside of Sochi, anyway), January’s global average surface temperature balanced out as the fourth warmest in the historical record.
Persistent cold temperatures in the Midwest this winter almost completely frozen over many of the Great Lakes. The Great Lakes Environmental Research Laboratory (GLERL) reported that 88 percent of the Great Lakes were frozen as of mid-February.
Models project that extreme dust events combined with global warming could advance the spring thaw in the mountains of the Upper Colorado River Basin by as many as 6 weeks by 2050. The earlier disappearance of snow could amplify water disputes, extend the fire season, and stress aquatic ecosystems.
Nearly ten percent of U.S. watersheds are living beyond their means when it comes to their water supply. For nearly half the country, water stress is projected to worsen by mid-century because of climate change, according to a recent NOAA-funded analysis.
Why do global climate models behave like they do? The Coupled Model Intercomparison Project (CMIP) panel—a subcommittee of the World Climate Research Programme—designs experiments to evaluate differences among climate models in how they simulate our global climate system and predict future changes.
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.
Glacier mass balance in 2011 (the most recent year for which worldwide analysis is complete) was negative, and preliminary data indicate that 2012 will probably be the 22nd consecutive year of net losses in glacier mass. Between 1980 and 2011, glaciers around the world lost the water equivalent of 15.7 meters. That would be like slicing a roughly 17-meter-thick slab off the top of the average glacier and repeating that exercise worldwide.