Recent trends in hydrologic balance have enhanced the terrestrial carbon sink in the United States
Article first published online: 28 MAY 2002
Copyright 2002 by the American Geophysical Union.
Geophysical Research Letters
Volume 29, Issue 10, pages 106-1–106-4, May 2002
How to Cite
Recent trends in hydrologic balance have enhanced the terrestrial carbon sink in the United States, Geophys. Res. Lett., 29(10), doi:10.1029/2002GL014867, 2002., , , , , , and ,
- Issue published online: 28 MAY 2002
- Article first published online: 28 MAY 2002
- Manuscript Accepted: 5 APR 2002
- Manuscript Revised: 30 MAR 2002
- Manuscript Received: 5 FEB 2002
 Climate data show significant increases in precipitation and humidity over the U.S. since 1900, yet the role of these hydro-climatic changes on the reported U.S. carbon sink is incompletely understood. Using a prognostic terrestrial ecosystem model, we simulated 1900–1993 continental U.S. carbon fluxes and found that increased growth by natural vegetation was associated with increased precipitation and humidity, especially during the 1950–1993 period. CO2 trends and warmer temperatures had a lesser effect. Two thirds of the increase in observed forest growth rates could be accounted for by observed climatic changes, including the confluence of earlier springs and wetter autumns leading to a lengthening of the vegetation carbon uptake period. However, regional differences in precipitation trends produced differing regional carbon sink responses. The strong coupling between carbon and hydrologic cycles implies that global carbon budget studies, currently dominated by temperature analyses, should consider changes in the hydrologic cycle.