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Title: Climate mitigation from vegetation biophysical feedbacks during the past three decades

Abstract

The surface air temperature response to vegetation changes has been studied for the extreme case of land-cover change; yet, it has never been quantified for the slow but persistent increase in leaf area index (LAI) observed over the past 30 years (Earth greening). We isolate the fingerprint of increasing LAI on surface air temperature using a coupled land–atmosphere global climate model prescribed with satellite LAI observations. Furthermore, we found that the global greening has slowed down the rise in global land-surface air temperature by 0.09 ± 0.02 °C since 1982. This net cooling effect is the sum of cooling from increased evapotranspiration (70%), changed atmospheric circulation (44%), decreased shortwave transmissivity (21%), and warming from increased longwave air emissivity (-29%) and decreased albedo (-6%). The global cooling originated from the regions where LAI has increased, including boreal Eurasia, Europe, India, northwest Amazonia, and the Sahel. Increasing LAI did not, but, significantly change surface air temperature in eastern North America and East Asia, where the effects of large-scale atmospheric circulation changes mask local vegetation feedbacks. Overall, the sum of biophysical feedbacks related to the greening of the Earth mitigated 12% of global land-surface warming for the past 30 years.

Authors:
 [1];  [2]; ORCiD logo [3];  [4];  [5];  [6];  [1];  [1]; ORCiD logo [7]; ORCiD logo [8]; ORCiD logo [9]; ORCiD logo [10];  [11]; ORCiD logo [1]; ORCiD logo [9]; ORCiD logo [12];  [13]
  1. Peking Univ., Beijing (China)
  2. Peking Univ., Beijing (China); Chinese Academy of Sciences (CAS), Beijing (China)
  3. Sorbonne Univ. Paris (France)
  4. State Univ. of New York (SUNY), Albany, NY (United States)
  5. Alternative Energies and Atomic Energy Commission (CEA), Gif-sur-Yvette (France)
  6. Chinese Academy of Sciences (CAS), Beijing (China)
  7. Princeton Univ., NJ (United States)
  8. Univ. of Exeter (United Kingdom)
  9. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  10. Princeton Univ., NJ (United States); Clark Univ., Worcester, MA (United States)
  11. Boston Univ., MA (United States)
  12. ETH Zurich (Switzerland)
  13. Commonwealth Scientific and Industrial Research Organization (CSIRO), Aspendale, VIC (Australia)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23)
OSTI Identifier:
1376650
DOE Contract Number:
AC05-00OR22725; SC0012534
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nature Climate Change; Journal Volume: 7; Journal Issue: 6
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; attribution; climate and earth system modelling; forest ecology; phenology

Citation Formats

Zeng, Zhenzhong, Piao, Shilong, Li, Laurent Z. X., Zhou, Liming, Ciais, Philippe, Wang, Tao, Li, Yue, Lian, Xu, Wood, Eric F., Friedlingstein, Pierre, Mao, Jiafu, Estes, Lyndon D., Myneni, Ranga B., Peng, Shushi, Shi, Xiaoying, Seneviratne, Sonia I., and Wang, Yingping. Climate mitigation from vegetation biophysical feedbacks during the past three decades. United States: N. p., 2017. Web. doi:10.1038/nclimate3299.
Zeng, Zhenzhong, Piao, Shilong, Li, Laurent Z. X., Zhou, Liming, Ciais, Philippe, Wang, Tao, Li, Yue, Lian, Xu, Wood, Eric F., Friedlingstein, Pierre, Mao, Jiafu, Estes, Lyndon D., Myneni, Ranga B., Peng, Shushi, Shi, Xiaoying, Seneviratne, Sonia I., & Wang, Yingping. Climate mitigation from vegetation biophysical feedbacks during the past three decades. United States. doi:10.1038/nclimate3299.
Zeng, Zhenzhong, Piao, Shilong, Li, Laurent Z. X., Zhou, Liming, Ciais, Philippe, Wang, Tao, Li, Yue, Lian, Xu, Wood, Eric F., Friedlingstein, Pierre, Mao, Jiafu, Estes, Lyndon D., Myneni, Ranga B., Peng, Shushi, Shi, Xiaoying, Seneviratne, Sonia I., and Wang, Yingping. Mon . "Climate mitigation from vegetation biophysical feedbacks during the past three decades". United States. doi:10.1038/nclimate3299.
@article{osti_1376650,
title = {Climate mitigation from vegetation biophysical feedbacks during the past three decades},
author = {Zeng, Zhenzhong and Piao, Shilong and Li, Laurent Z. X. and Zhou, Liming and Ciais, Philippe and Wang, Tao and Li, Yue and Lian, Xu and Wood, Eric F. and Friedlingstein, Pierre and Mao, Jiafu and Estes, Lyndon D. and Myneni, Ranga B. and Peng, Shushi and Shi, Xiaoying and Seneviratne, Sonia I. and Wang, Yingping},
abstractNote = {The surface air temperature response to vegetation changes has been studied for the extreme case of land-cover change; yet, it has never been quantified for the slow but persistent increase in leaf area index (LAI) observed over the past 30 years (Earth greening). We isolate the fingerprint of increasing LAI on surface air temperature using a coupled land–atmosphere global climate model prescribed with satellite LAI observations. Furthermore, we found that the global greening has slowed down the rise in global land-surface air temperature by 0.09 ± 0.02 °C since 1982. This net cooling effect is the sum of cooling from increased evapotranspiration (70%), changed atmospheric circulation (44%), decreased shortwave transmissivity (21%), and warming from increased longwave air emissivity (-29%) and decreased albedo (-6%). The global cooling originated from the regions where LAI has increased, including boreal Eurasia, Europe, India, northwest Amazonia, and the Sahel. Increasing LAI did not, but, significantly change surface air temperature in eastern North America and East Asia, where the effects of large-scale atmospheric circulation changes mask local vegetation feedbacks. Overall, the sum of biophysical feedbacks related to the greening of the Earth mitigated 12% of global land-surface warming for the past 30 years.},
doi = {10.1038/nclimate3299},
journal = {Nature Climate Change},
number = 6,
volume = 7,
place = {United States},
year = {Mon May 22 00:00:00 EDT 2017},
month = {Mon May 22 00:00:00 EDT 2017}
}
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