climate variability

Natural variability alone cannot explain the recent (past century) warming trend, confirms a new study published in Nature Geoscience.

Warming in recent decades, coupled with natural climate variations, has intensified the summer monsoon system across Asia, West Africa, and North America, according to a recent paper in PNAS.

Global temperatures in 2011 were the coolest since 2008, but they were still above the 1981-2010 average and the year was one of the 15 warmest on record.

Scientists find that emissions of black carbon aerosols—small atmospheric particles—and tropospheric ozone, pollutants mostly emitted by countries in the low- to mid-latitudes of the Northern Hemisphere, are expanding the width of the tropical boundary.

Three new analyses on climate extremes together explain how extremes may change in the future, what’s driving them, their impacts on people and ecosystems, and how we can adapt. The most extensive report is from the Intergovernmental Panel on Climate Change (IPCC) and it details the current state of knowledge on climate extremes.

Melting Arctic sea ice in recent decades is linked to changes in atmospheric circulation over the Northern Hemisphere during winter, resulting in increased cold surges over large parts of North America, Europe, and eastern Asia, according to a recent study in PNAS .

The new Winter Outlook from NOAA predicts La Niña to gradually strengthen and continue through the winter, resulting in warmer and drier conditions for the Southwest.

According to the newest State of the Climate by NOAA, September was 1.5°F warmer than average across the U.S. Average precipitation, on the other hand, was near normal with most of the eastern half of the U.S.

Posted by Zack Guido | on September 21, 2011
Raging fires, mile-high walls of dust, bone-dry drought, and pipe-bursting freezes wreaked havoc across the Southwest this year. By the end of August, drought and fires alone cost New Mexico, Arizona, Texas, and other western states more than $5 billion, which does not include the recent blazes that destroyed more than 1,000 of houses in Texas. Ten disasters across the country have cost more than $1 billion already this year, breaking the previous record of nine set in 2008, according to the National Oceanic and Atmospheric Administration (NOAA). In fact, CNN dubbed 2011 the year of billion-dollar disasters (August 20).

NOAA and the National Climatic Data Center recently released the State of the Climate overview for August and the entire summer, and the verdict is in: this was the second warmest summer on record for the U.S. It was also dry, with precipitation averaging 1.0 inch below the long-term average.