TY - JOUR
T1 - On the role of a coupled vegetation-runoff system in simulating the tropical African climate
T2 - a regional climate model sensitivity study
AU - Anwar, Samy A.
AU - Diallo, Ismaila
N1 - Funding Information:
The OFID-ICTP is acknowledged for supporting the fund for the step program supported by the International Centre for Theoretical Physics (ICTP) institute. The climate group in Earth System Physics (ESP) of the ICTP is acknowledged for providing the RegCM code, computational facilities and input data to run the model. Ismaila Diallo is supported by the U.S. National Science Foundation grant AGS-1419526. Climate Research Unit (CRU) of University of East Anglia is acknowledged for providing dataset of 2-m mean air temperature. Thanks for Dr. Martin Jung for providing the up-scaled flux-net dataset of latent and sensible heat fluxes (MTE dataset) through the BGI portal. MSWEP product is retrieved from the website http://www.gloh2o.org . NCEP/NCAR2 reanalysis data is provided by the NOAA/OAR/ESRL PSD, Boulder, Colorado, USA, from their Web site at http://www.esrl.noaa.gov/psd/ . We would like also thank the editor and anonymous reviewers for their constructive comments, which have helped to improve the overall quality of the manuscript.
Funding Information:
The OFID-ICTP is acknowledged for supporting the fund for the step program supported by the International Centre for Theoretical Physics (ICTP) institute. The climate group in Earth System Physics (ESP) of the ICTP is acknowledged for providing the RegCM code, computational facilities and input data to run the model. Ismaila Diallo is supported by the U.S. National Science Foundation grant AGS-1419526. Climate Research Unit (CRU) of University of East Anglia is acknowledged for providing dataset of 2-m mean air temperature. Thanks for Dr. Martin Jung for providing the up-scaled flux-net dataset of latent and sensible heat fluxes (MTE dataset) through the BGI portal. MSWEP product is retrieved from the website http://www.gloh2o.org. NCEP/NCAR2 reanalysis data is provided by the NOAA/OAR/ESRL PSD, Boulder, Colorado, USA, from their Web site at http://www.esrl.noaa.gov/psd/. We would like also thank the editor and anonymous reviewers for their constructive comments, which have helped to improve the overall quality of the manuscript.
Publisher Copyright:
© 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.
PY - 2021/7
Y1 - 2021/7
N2 - The role of vegetation-runoff system—in simulating the tropical African climate—was examined by analysing two 13-year simulations with two runoff schemes of the community land model version 4.5 (CLM45): the default one is TOPMODEL (TOP) and the other one is the Variable Infiltration Capacity (VIC) using a regional climate model (RegCM4-CLM45). In both simulations, the carbon-nitrogen (CN) module was activated. The first simulation was referred to as CN-TOP, while the second one was designated as CN-VIC. Overall, the results showed that the CN-VIC severely decreases the leaf area index (LAI), vegetation transpiration and soil evaporation relative to the CN-TOP. Eventually, it severely underestimates the total evapotranspiration but overestimates the sensible heat flux in comparison with the reanalysis product; meanwhile the CN-TOP opposes this effect. As a result, the CN-TOP shows a strong cold bias, and the CN-VIC shows a slightly warm bias in comparison with the observation. Moreover, enabling the interactive vegetation module leads to intensifying the dry bias of the total surface precipitation in both simulations with respect to the static vegetation case against the reanalysis product; however the CN-VIC still outperforms the CN-TOP in comparison with the observations. In conclusion, the coupled vegetation-runoff system has a strong influence on the tropical African climate relative to the static case, and calibrating the four parameters of the VIC surface dataset ensures a better and more reliable performance of the coupled RegCM4-CLM45-CN-VIC model for simulating the tropical African climate.
AB - The role of vegetation-runoff system—in simulating the tropical African climate—was examined by analysing two 13-year simulations with two runoff schemes of the community land model version 4.5 (CLM45): the default one is TOPMODEL (TOP) and the other one is the Variable Infiltration Capacity (VIC) using a regional climate model (RegCM4-CLM45). In both simulations, the carbon-nitrogen (CN) module was activated. The first simulation was referred to as CN-TOP, while the second one was designated as CN-VIC. Overall, the results showed that the CN-VIC severely decreases the leaf area index (LAI), vegetation transpiration and soil evaporation relative to the CN-TOP. Eventually, it severely underestimates the total evapotranspiration but overestimates the sensible heat flux in comparison with the reanalysis product; meanwhile the CN-TOP opposes this effect. As a result, the CN-TOP shows a strong cold bias, and the CN-VIC shows a slightly warm bias in comparison with the observation. Moreover, enabling the interactive vegetation module leads to intensifying the dry bias of the total surface precipitation in both simulations with respect to the static vegetation case against the reanalysis product; however the CN-VIC still outperforms the CN-TOP in comparison with the observations. In conclusion, the coupled vegetation-runoff system has a strong influence on the tropical African climate relative to the static case, and calibrating the four parameters of the VIC surface dataset ensures a better and more reliable performance of the coupled RegCM4-CLM45-CN-VIC model for simulating the tropical African climate.
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U2 - 10.1007/s00704-021-03627-8
DO - 10.1007/s00704-021-03627-8
M3 - Article
AN - SCOPUS:85105369438
SN - 0177-798X
VL - 145
SP - 313
EP - 325
JO - Theoretical and Applied Climatology
JF - Theoretical and Applied Climatology
IS - 1-2
ER -