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, 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.
Field research provides new data advancing our ability to project how tropical forests will respond to a changing climate. Tropical forests store vast amounts of carbon and play a key role in regulating Earth’s climate. As climate changes, these ecosystems have the potential to become a net contributor to global warming if they shift to releasing more carbon to the atmosphere than they absorb 1 . However, how these forests will be affected by a warming climate and changing atmosphere is still uncertain, and is critical for improving model projections of future climate change 2 . In the first...