ClimateWatch

Arctic sea ice extent set a new record low at the end of the summer melt season on September 16, 2012. But extent is not the only quality of the ice that is changing. Wind and ocean circulation patterns are conspiring with a warmer climate to reduce the amount of year-round (multi-year) ice, transforming the remaining ice into a younger, thinner version of its old self.

The rainy season in India arrived late and delivered far less precipitation than usual in summer 2012, leading to severe drought across large parts of the country. More than half the labor force in India makes a living in agriculture, which makes drought a widespread social and economic hardship.

In a place routinely afflicted by drought, water managers in Tampa Bay use climate forecasts to ensure a water supply to people’s taps without sucking the region’s rivers, wetlands, and groundwater dry. The limits of their innovation might be tested in a future which could pose even more challenges to ensuring the oasis remains green.

A scorching July contributed to the third hottest summer on record for the contiguous United States. Most of the U.S. was also drier than average. Rains from Isaac did little to relieve drought.

Imagine heat waves like the one in July 2012 coming more often & lasting longer: that’s the projection from climate models for the middle of this century based on one future emissions path.

As of August 26, Arctic sea ice appears to have broken the 2007 record for smallest daily extent of the satellite era. The pace of ice melt in late August 2012 was roughly 29,000 square miles per day, nearly double the normal rate for this time of year.

A series of unusually strong, long-lasting high pressure systems has parked over Greenland this summer. As many a weather forecaster has explained, high pressure generally leads to calm winds and sunny skies, both of which boost temperatures during the all-day sunshine of mid-summer at high latitudes. The conditions contributed to widespread melting of the ice sheet.