Much of the precipitation along the U.S. West Coast is delivered by phenomena known as “atmospheric rivers”—narrow bands of moist air that may extend for thousands of miles across regions outside of the tropics, and play a critical role in regional water supply and storm activity. Atmospheric-river events play a beneficial role in building up Western water supply and snowpack but are also the source of a large majority of floods in the region. Many uncertainties about key processes that affect storm development...
Highlights
Since 1989, the U.S. Global Change Research Program (USGCRP) has submitted annual reports to Congress called Our Changing Planet. The reports describe the status of USGCRP research activities, provide progress updates, and document recent accomplishments
In particular, Our Changing Planet highlights progress and accomplishments in interagency activities. These highlights represent the broad spectrum of USGCRP activities that extend from Earth system observations, modeling, and fundamental research through synthesis and assessment, decision support, education, and public engagement. Highlights describe the state of science at the time of publication of each yearly report, and may not reflect more recent advances in understanding. The date of publication of the source report is noted on each highlight page.
On February 11, 2016, workers in California ended the largest reported natural gas leak in U.S. history. The Aliso Canyon leak released methane and other gases into the atmosphere from an underground-storage facility for over three months, causing the evacuation of more than 5,000 households. Researchers from NOAA, NASA, Scientific Aviation, the University of California, the National Institute of Standards and Technology (NIST), the California Air Resources Board, and South Coast Air Quality Management District mobilized rapidly to assess the environmental impacts of the leak,...

The Arctic tundra is a cold, desert-like biome, with a layer of permanently frozen soil and organic matter below the surface containing vast stocks of carbon. As Arctic tundra soils warm in response to climate change, methane emissions from decomposing organic material could increase dramatically, representing a potentially significant positive feedback on climate warming. However, seasonal and climatic influences on methane emissions from these systems are not well understood outside of the summer months, representing a major uncertainty for the Arctic methane budget. To help address a...