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.
A major winter storm was still blustering its way through the U.S. Northeast this morning, with continued snow accumulations and high winds predicted for many areas. How will this event compare to the region’s most historic storms?
Just for fun, we asked the experts at the Rutgers Snow Lab to show us what their data (based on NOAA satellite images) had to say about whether the number of snow-covered days during the week of Christmas has changed at all across the U.S. in the past 50 years.
The Antarctic ozone hole did not cause global warming. But there is a connection between climate and the annual thin spot that forms each spring in Earth’s UV-blocking ozone layer: colder winter temperatures tend to lead to larger ozone holes.
NOAA’s National Climatic Data Center announced that last month was the warmest September on record for the planet. If the surface temperature remains elevated at the same level for the remainder of the year, 2014 will set a new record for the warmest annual average temperature since records began in 1880.
Last September’s widespread flooding in northeast Colorado, which saw just over 17 inches of rain in one week in the city of Boulder, was not made more likely or more intense by the influence of human-induced climate change on atmospheric moisture.
Temperature extremes have been pretty unusual across the United States so far in 2014. Looking back over this time period quickly reveals at least part of what was going on: the polar jet stream got into a serious rut.