www.hydrol-earth-syst-sci.net/13/759/2009/ doi:10.5194/hess-13-759-2009 © Author(s) 2009. This work is distributed under the Creative Commons Attribution 3.0 License. Influence of thermodynamic soil and vegetation parameterizations on the simulation of soil temperature states and surface fluxes by the Noah LSM over a Tibetan plateau site 1International Institute for Geo-Information Science and Earth Observation (ITC), Hengelosestraat 99, P.O. Box 6, 7500 AA Enschede, The Netherlands 2Environmental Modeling Center, National Center for Environmental Prediction, Suitland, Maryland, USA 3Hydrological Science Branch, Code 614.3, NASA, Goddard Space Flight Center, Greenbelt, Maryland, USA 4Institute of Tibetan Plateau Research (ITP/CAS), P.O. Box 2871, Beijing 100085, China Abstract. In this paper, we investigate the ability of the Noah Land Surface Model (LSM) to simulate temperature states in the soil profile and surface fluxes measured during a 7-day dry period at a micrometeorological station on the Tibetan Plateau. Adjustments in soil and vegetation parameterizations required to ameliorate the Noah simulation on these two aspects are presented, which include: (1) differentiating the soil thermal properties of top- and subsoils, (2) investigation of the different numerical soil discretizations and (3) calibration of the parameters utilized to describe the transpiration dynamics of the Plateau vegetation. Through the adjustments in the parameterization of the soil thermal properties (STP) simulation of the soil heat transfer is improved, which results in a reduction of Root Mean Squared Differences (RMSD's) by 14%, 18% and 49% between measured and simulated skin, 5-cm and 25-cm soil temperatures, respectively. Further, decreasing the minimum stomatal resistance (Rc,min) and the optimum temperature for transpiration (Topt) of the vegetation parameterization reduces RMSD's between measured and simulated energy balance components by 30%, 20% and 5% for the sensible, latent and soil heat flux, respectively. Final Revised Paper (PDF, 2583 KB) Discussion Paper (HESSD) Citation: van der Velde, R., Su, Z., Ek, M., Rodell, M., and Ma, Y.: Influence of thermodynamic soil and vegetation parameterizations on the simulation of soil temperature states and surface fluxes by the Noah LSM over a Tibetan plateau site, Hydrol. Earth Syst. Sci., 13, 759-777, doi:10.5194/hess-13-759-2009, 2009. Bibtex EndNote Reference Manager XML |