TY - JOUR
T1 - Productivity of North American grasslands is increased under future climate scenarios despite rising aridity
AU - Hufkens, Koen
AU - Keenan, Trevor F.
AU - Flanagan, Lawrence B.
AU - Scott, Russell L.
AU - Bernacchi, Carl J.
AU - Joo, Eva
AU - Brunsell, Nathaniel A.
AU - Verfaillie, Joseph
AU - Richardson, Andrew D.
N1 - Publisher Copyright:
© 2016 Macmillan Publishers Limited. All rights reserved.
PY - 2016/7/1
Y1 - 2016/7/1
N2 - Grassland productivity is regulated by both temperature and the amount and timing of precipitation. Future climate change is therefore expected to influence grassland phenology and growth, with consequences for ecosystems and economies. However, the interacting effects of major shifts in temperature and precipitation on grasslands remain poorly understood and existing modelling approaches, although typically complex, do not extrapolate or generalize well and tend to disagree under future scenarios. Here we explore the potential responses of North American grasslands to climate change using a new, data-informed vegetation-hydrological model, a network of high-frequency ground observations across a wide range of grassland ecosystems and CMIP5 climate projections. Our results suggest widespread and consistent increases in vegetation fractional cover for the current range of grassland ecosystems throughout most of North America, despite the increase in aridity projected across most of our study area. Our analysis indicates a likely future shift of vegetation growth towards both earlier spring emergence and delayed autumn senescence, which would compensate for drought-induced reductions in summer fractional cover and productivity. However, because our model does not include the effects of rising atmospheric CO 2 on photosynthesis and water use efficiency, climate change impacts on grassland productivity may be even larger than our results suggest. Increases in the productivity of North American grasslands over this coming century have implications for agriculture, carbon cycling and vegetation feedbacks to the atmosphere.
AB - Grassland productivity is regulated by both temperature and the amount and timing of precipitation. Future climate change is therefore expected to influence grassland phenology and growth, with consequences for ecosystems and economies. However, the interacting effects of major shifts in temperature and precipitation on grasslands remain poorly understood and existing modelling approaches, although typically complex, do not extrapolate or generalize well and tend to disagree under future scenarios. Here we explore the potential responses of North American grasslands to climate change using a new, data-informed vegetation-hydrological model, a network of high-frequency ground observations across a wide range of grassland ecosystems and CMIP5 climate projections. Our results suggest widespread and consistent increases in vegetation fractional cover for the current range of grassland ecosystems throughout most of North America, despite the increase in aridity projected across most of our study area. Our analysis indicates a likely future shift of vegetation growth towards both earlier spring emergence and delayed autumn senescence, which would compensate for drought-induced reductions in summer fractional cover and productivity. However, because our model does not include the effects of rising atmospheric CO 2 on photosynthesis and water use efficiency, climate change impacts on grassland productivity may be even larger than our results suggest. Increases in the productivity of North American grasslands over this coming century have implications for agriculture, carbon cycling and vegetation feedbacks to the atmosphere.
UR - http://www.scopus.com/inward/record.url?scp=84975796855&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84975796855&partnerID=8YFLogxK
U2 - 10.1038/nclimate2942
DO - 10.1038/nclimate2942
M3 - Article
AN - SCOPUS:84975796855
SN - 1758-678X
VL - 6
SP - 710
EP - 714
JO - Nature Climate Change
JF - Nature Climate Change
IS - 7
ER -