Finding optimal Noah-MP parameterizations for the characterization of surface heat fluxes in the Iberian Peninsula
Abstract
Land surface models (LSMs) play a crucial role in characterizing land-atmosphere interactions by providing boundary conditions to regional climate models (RCMs). This is particularly true over the Iberian Peninsula (IP), where a water-limited regime governs much of the territory. We optimize the configuration of the Noah land surface model with multiparameterization options (Noah-MP) for characterizing heat fluxes in the IP when the Weather Research and Forecasting (WRF) model v3.9.1 is used as an RCM. We perform 70 one-year simulations using 35 Noah-MP combinations, for a dry year (2005) and a wet year (2010). Land-surface heat fluxes and soil moisture from WRF/Noah-MP are evaluated against FLUXNET station data and the CERRA-Land reanalysis. In general, WRF/Noah-MP reproduces soil moisture and surface heat fluxes well over the IP, especially under wetter conditions. Clustering identifies an optimal configuration from 10 groups (A to J). The Noah-MP options with greatest impact are canopy stomatal resistance (CRS), surface exchange coefficient for heat (SFC), soil-moisture factor controlling stomatal resistance (BTR), runoff and groundwater (RUN), and surface resistance to evaporation/sublimation (RSF); dynamic vegetation (DVEG) also matters. Several configurations performed reasonably; experiment s27I (Jarvis CRS, Chen97 SFC, CLM-type BTR, BATS RUN, and adjusted Sellers RSF for wet soils) provides a particularly good characterization of heat fluxes over the IP.