The basic GISS temperature analysis scheme was defined in the late 1970s by James Hansen when a method of estimating global temperature change was needed for comparison with one-dimensional global climate models. Prior temperature analyses, most notably those of Murray Mitchell, covered only 20-90°N latitudes. Our first published results (Hansen et al. 1981) showed that, contrary to impressions f ... read more >>

Last spring, I noted that recent global temperatures seemed to be primarily a combination of a long-term trend and modulation by El Niño and La Niña (here and here). In September, I took this idea one step further and issued global temperature anomaly forecasts for 2012 and 2013 based entirely on a linear trend plus ENSO (here). Today, we see how the 2012 forecast turned out, and update the for ... read more >>

In my article in Tuesday’s Science Times about the risks of long-term sea level rise, and in an accompanying podcast, I reported on the link between past instances of global warming, caused by natural fluctuations in the climate, and higher shorelines.

Based on a study of these past variations, some scientists believe that even if we stopped burning fossil fuels tomorrow, we would be due for a ... read more >>

The Tigris and Euphrates river basins, at the heart of the Fertile Crescent, lost enough fresh water between 2003 and 2009 to fill the Dead Sea, according to a study that used NASA satellite data to measure hydrological changes in parts of Turkey, Syria, Iraq, and western Iran. One-fifth of the net water loss was attributed to dry soils and a withered snowpack, the study found. Evaporation from l ... read more >>

The destruction of the Aral Sea in Central Asia has been called the world's worst environmental disaster. It's not something we should be repeating, especially in a time of growing uncertainty about water resources on our warming planet.

So will the world stand by (and even underwrite the perpetrators) as Ethiopia builds projects that will suck dry one of Africa's largest lakes, and create "wa ... read more >>

As Texas' drought wears into its third year, water fights are accelerating within the state as farmers, cities and industry compete for limited supplies from dwindling reservoirs. But many of these seem like small-scale skirmishes compared with the complex and high-stakes battles along Texas' borders that stem from pacts signed decades ago.
Texas is currently locked in a legal conflict over wat ... read more >>

New estimates from a Norwegian research project show that policymakers attempting to contain global warming at less than 3.6 degrees Fahrenheit have an attainable target. While most news that comes out about global warming is typically negative and ominous, this study has put a slightly more positive twist on the unfolding story of climate change. “These results are truly sensational,” said Carol ... read more >>

The past 12 months were the second wettest on record in the UK, according to data released by the Met Office. The total rainfall for the UK during 2012 was 1,330.7mm (52.4in), just 6.6mm short of the record set in 2000. Most areas were affected by the extreme weather, with thousands of homes flooded and farmers struggling to grow crops in the saturated soil. The latest data comes as analysis says ... read more >>

With the European land surface warming rapidly, rainfall patterns changing and sea levels rising ever faster, southern Europe will suffer most from climate change. But there is an urgent need for countries across the continent to adapt to change, according to the European Environment Agency. ... read more >>

As warming alters the Arctic landscape, people are paying more attention to the changes happening to the Greenland Ice Sheet. The ice is melting more rapidly than before, leaving us to wonder, what’s going on?

To help answer your questions about Greenland, NSIDC’s newest Web site, Greenland Ice Sheet Today, will feature the latest research and imagery that researchers are using to monitor the ... read more >>