TY - JOUR
T1 - Sampling bias overestimates climate change impacts on forest growth in the southwestern United States
AU - Klesse, Stefan
AU - DeRose, R. Justin
AU - Guiterman, Christopher H.
AU - Lynch, Ann M.
AU - O’Connor, Christopher D.
AU - Shaw, John D.
AU - Evans, Margaret E.K.
N1 - Funding Information:
The authors would like to thank the many people who contributed to and maintained the ITRDB, as well as the field and laboratory crew involved in the establishment of the Interior West FIA tree-ring data network, especially Alex Arizpe, Jacob Aragon, Andrew Gray, and Joey Pettit. We thank the Navajo Forestry Department for permission to include the data from Navajo forest lands in the analysis. We are grateful to David Frank for critical discussions of this work. Our thanks also go to Nichole Casebeer and Cara Gibson for their help in creating Fig. 1, and to Ben Hickson for assistance with Figs. 2 and 4. S.K. acknowledges the support of the USDA-AFRI grant 2016-67003-24944; M.E. K.E. was supported by the University of Arizona College of Science and Institute of the Environment. C.H.G. is supported by an EPA STAR Fellowship (#F13F51318) and a grant from the Navajo Nation (contract CO1142).
Publisher Copyright:
© 2018, The Author(s).
PY - 2018/12/1
Y1 - 2018/12/1
N2 - Climate−tree growth relationships recorded in annual growth rings have recently been the basis for projecting climate change impacts on forests. However, most trees and sample sites represented in the International Tree-Ring Data Bank (ITRDB) were chosen to maximize climate signal and are characterized by marginal growing conditions not representative of the larger forest ecosystem. We evaluate the magnitude of this potential bias using a spatially unbiased tree-ring network collected by the USFS Forest Inventory and Analysis (FIA) program. We show that U.S. Southwest ITRDB samples overestimate regional forest climate sensitivity by 41–59%, because ITRDB trees were sampled at warmer and drier locations, both at the macro- and micro-site scale, and are systematically older compared to the FIA collection. Although there are uncertainties associated with our statistical approach, projection based on representative FIA samples suggests 29% less of a climate change-induced growth decrease compared to projection based on climate-sensitive ITRDB samples.
AB - Climate−tree growth relationships recorded in annual growth rings have recently been the basis for projecting climate change impacts on forests. However, most trees and sample sites represented in the International Tree-Ring Data Bank (ITRDB) were chosen to maximize climate signal and are characterized by marginal growing conditions not representative of the larger forest ecosystem. We evaluate the magnitude of this potential bias using a spatially unbiased tree-ring network collected by the USFS Forest Inventory and Analysis (FIA) program. We show that U.S. Southwest ITRDB samples overestimate regional forest climate sensitivity by 41–59%, because ITRDB trees were sampled at warmer and drier locations, both at the macro- and micro-site scale, and are systematically older compared to the FIA collection. Although there are uncertainties associated with our statistical approach, projection based on representative FIA samples suggests 29% less of a climate change-induced growth decrease compared to projection based on climate-sensitive ITRDB samples.
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U2 - 10.1038/s41467-018-07800-y
DO - 10.1038/s41467-018-07800-y
M3 - Article
C2 - 30559441
AN - SCOPUS:85058730188
VL - 9
JO - Nature Communications
JF - Nature Communications
SN - 2041-1723
IS - 1
M1 - 5336
ER -