Jones, Julia A.; Creed, Irena F.; Hatcher, Kendra L.; Warren, Robert J.; Adams, Mary Beth; Benson, Melinda H.; Boose, Emery; Brown, Warren A.; Campbell, John L.; Covich, Alan; Clow, David W.; Dahm, Clifford N.; Elder, Kelly; Ford, Chelcy R.; Grimm, Nancy B.; Henshaw, Donald L.; Larson, Kelli L.; Miles, Evan S.; Miles, Kathleen M.; Sebestyen, Stephen D.; Spargo, Adam T.; Stone, Asa B.; Vose, James M.; Williams, Mark W. 2012. Ecosystem processes and human influences regulate streamflow response to climate change at Long-Term Ecological Research sites. BioScience. 62(4): 390-404. doi:https://doi.org/10.1525/bio.2012.62.4.10.
Analyses of long-term records at 35 headwater basins in the United States and Canada indicate that climate change effects on streamflow are not
as clear as might be expected, perhaps because of ecosystem processes and human influences. Evapotranspiration was higher than was predicted by
temperature in water-surplus ecosystems and lower than was predicted in water-deficit ecosystems. Streamflow was correlated with climate variability
indices (e.g., the El Niño–Southern Oscillation, the Pacific Decadal Oscillation, the North Atlantic Oscillation), especially in seasons when
vegetation influences are limited. Air temperature increased significantly at 17 of the 19 sites with 20- to 60-year records, but streamflow trends were
directly related to climate trends (through changes in ice and snow) at only 7 sites. Past and present human and natural disturbance, vegetation
succession, and human water use can mimic, exacerbate, counteract, or mask the effects of climate change on streamflow, even in reference basins.
Long-term ecological research sites are ideal places to disentangle these processes.
Keywords: precipitation/runoff ratio, trend, succession, socioecological systems, Budyko curve