Human-modified temperatures induce species changes: Joint attribution.
Average global surface-air temperature is increasing. Contention exists over relative contributions by natural and anthropogenic forcings. Ecological studies attribute plant and animal changes to observed warming. Until now, temperature-species connections have not been statistically attributed directly to anthropogenic climatic change. Using modeled climatic variables and observed species data, which are independent of thermometer records and paleoclimatic proxies, we demonstrate statistically significant "joint attribution," a two-step linkage: human activities contribute significantly to temperature changes and human-changed temperatures are associated with discernible changes in plant and animal traits. Additionally, our analyses provide independent testing of grid-box-scale temperature projections from a general circulation model (HadCM3).
Root
Terry L
TL
Center for Environmental Science and Policy, Stanford Institute for International Studies, Stanford University, Stanford, CA 94305-6055, USA. troot@stanford.edu
MacMynowski
Dena P
DP
Mastrandrea
Michael D
MD
Schneider
Stephen H
SH
D003198:Computer Simulation; D017753:Ecosystem; D017752:Greenhouse Effect; D006802:Human Activities; D008962:Models, Theoretical; D009010:Monte Carlo Method; D013045:Species Specificity; D013696:Temperature; D013997:Time Factors