EGU21-4510
https://doi.org/10.5194/egusphere-egu21-4510
EGU General Assembly 2021
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Assessment and Improvement of Noah-MP over the Tibetan grasslands in growing season

Shuang Sun1, Donghai Zheng2, Shaomin Liu3, Ziwei Xu4, Tongren Xu5, Hui Zheng6, and Xiaofan Yang7
Shuang Sun et al.
  • 1State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China (shsun@mail.bnu.edu.cn)
  • 2National Tibetan Plateau Data Center, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China (zhengd@itpcas.ac.cn)
  • 3State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China (smliu@bnu.edu.cn)
  • 4State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China (xuzw@bnu.edu.cn)
  • 5State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China (xutr@bnu.edu.cn)
  • 6CAS Key Laboratory of Regional Climate-Environment Research for Temperate East Asia, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China (zhenghui@tea.ac.cn)
  • 7State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China (xfyang@bnu.edu.cn)

The Tibetan grasslands has very strong land-air interactions and plays an important role in the regional climate system of the Tibetan Plateau and understanding of land-air interactions in the Tibetan grasslands is significantly important for the sustainable development of it under the climate change. In this paper, we assessed the Noah-MP by conducting ensemble experiments for analyzing the sensitive physical processes, and selected the optimal combinations of parameterization options at four alpine meadow sites in the Tibetan grassland ecosystems. Measurements collected from four study sites over the Tibetan grassland ecosystems in the Heihe Watershed Allied Telemetry Experimental Research (HiWATER) are used. The results showed that the dynamic vegetation (Dveg), the canopy stomatal resistance (Crs), the runoff and the groundwater (Run) and the surface exchange coefficient (Sfc) physical processes are the most sensitive control physical processes for energy and water fluxes in the Tibetan grassland ecosystems. Importantly, the optimal combination of parameterization options in Noah-MP overestimates the sensible heat flux (H) and underestimates soil moisture (θ) obviously. After finding the problems in the simulations outputed by the optimal combination of parameterization options, two groups of improved experiments were conducted to find out the reason. We found that the improved calculation of the surface exchange coefficient can alleviate the overestimation H, and the improved method of soil parameters considering the soil organic carbon (SOC) and an exponential form of root vertical distribution for each soil layers can effectively solve the underestimation of θ at all four sites.

How to cite: Sun, S., Zheng, D., Liu, S., Xu, Z., Xu, T., Zheng, H., and Yang, X.: Assessment and Improvement of Noah-MP over the Tibetan grasslands in growing season, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-4510, https://doi.org/10.5194/egusphere-egu21-4510, 2021.

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