The June round of our “Climate Challenge” social media game pitted experts against players to answer the following question: What percent area of the United States will be in severe drought or worse in June 2015?
Some of the chemicals that replaced ozone-harming CFCs are long-lived greenhouse gases. At NOAA's lab in Boulder, Colorado, chemist Steve Montzka leads the effort to monitor the concentration of CFC-substitutes and their potential impact on global warming.
Few things are more important to California’s water supply than the water content of the mountain snowpack at the start of the state’s warm season. In the latest round of our Climate Challenge game, experts and participants predicted the water content of the Sierra Nevada snowpack on May 1, 2015. The answer was disturbingly low.
For 800,000 years before the twentieth century, carbon dioxide levels in Earth’s atmosphere never exceeded 300 parts per million. In March 2015, the monthly average went above 400 ppm for the first time.
A new analysis suggests that in the winter following a La Niña, dryness in California often deepens into drought. Consistent with that pattern, California’s current drought began in 2011-12, during the second year of a La Niña episode.