TY - JOUR
T1 - Revisiting the contribution of transpiration to global terrestrial evapotranspiration
AU - Wei, Zhongwang
AU - Yoshimura, Kei
AU - Wang, Lixin
AU - Miralles, Diego G.
AU - Jasechko, Scott
AU - Lee, Xuhui
PY - 2017/3/28
Y1 - 2017/3/28
N2 - Even though knowing the contributions of transpiration (T), soil and open water evaporation (E), and interception (I) to terrestrial evapotranspiration (ET = T + E + I) is crucial for understanding the hydrological cycle and its connection to ecological processes, the fraction of T is unattainable by traditional measurement techniques over large scales. Previously reported global mean T/(E + T + I) from multiple independent sources, including satellite-based estimations, reanalysis, land surface models, and isotopic measurements, varies substantially from 24% to 90%. Here we develop a new ET partitioning algorithm, which combines global evapotranspiration estimates and relationships between leaf area index (LAI) and T/(E + T) for different vegetation types, to upscale a wide range of published site-scale measurements. We show that transpiration accounts for about 57.2% (with standard deviation ± 6.8%) of global terrestrial ET. Our approach bridges the scale gap between site measurements and global model simulations,and can be simply implemented into current global climate models to improve biological CO2 flux simulations.
AB - Even though knowing the contributions of transpiration (T), soil and open water evaporation (E), and interception (I) to terrestrial evapotranspiration (ET = T + E + I) is crucial for understanding the hydrological cycle and its connection to ecological processes, the fraction of T is unattainable by traditional measurement techniques over large scales. Previously reported global mean T/(E + T + I) from multiple independent sources, including satellite-based estimations, reanalysis, land surface models, and isotopic measurements, varies substantially from 24% to 90%. Here we develop a new ET partitioning algorithm, which combines global evapotranspiration estimates and relationships between leaf area index (LAI) and T/(E + T) for different vegetation types, to upscale a wide range of published site-scale measurements. We show that transpiration accounts for about 57.2% (with standard deviation ± 6.8%) of global terrestrial ET. Our approach bridges the scale gap between site measurements and global model simulations,and can be simply implemented into current global climate models to improve biological CO2 flux simulations.
KW - ET partitioning algorithm
KW - site measurements
KW - transpiration
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U2 - 10.1002/2016GL072235
DO - 10.1002/2016GL072235
M3 - Article
AN - SCOPUS:85017380025
VL - 44
SP - 2792
EP - 2801
JO - Geophysical Research Letters
JF - Geophysical Research Letters
SN - 0094-8276
IS - 6
ER -