Parameterization of Surface Layer Processes under Stable Conditions over Mountainous Region

Representation of the exchange of heat, momentum, and moisture between the earth surface and the atmosphere in the stable atmospheric surface layer remains an intricate challenge in weather and climate modelling over mountainous regions. Mostly these representations in the weather and climate models are based on Monin–Obukhov Similarity Theory (MOST) and depend on the stability correction functions. In this study, along with default (Cheng and Brutsaert, 2005), two more nonlinear stability correction functions for momentum and sensible heat fluxes under stable atmospheric conditions suggested by Grachev et al. (2007) and Srivastava et al. (2020) are implemented in the Weather Research and Forecasting (WRFv4.3.3) Model for simulating the fair-weather condition over Uttarakhand, India. The high resolution WRF year-long simulations for each case was carried out over Uttarakhand, India. Further, the model outputs are evaluated against reanalysis data and high-frequency turbulent data collected over a year (Nov 2024 to Oct 2025) from a CSAT3 three-dimensional sonic anemometer installed at 27-meter on the tower of 30 meters in Ranichauri, Uttarakhand (30.309° N, 78.408° E) with an average altitude of 1950 meters above mean sea level. The results indicate that stability correction function suggested by Grachev et al. (2007) are outperforming the default one and the Srivastava et al. (2020) formulation. The study recommends further steps toward parameterizing surface atmosphere turbulent exchange processes under stable stratifications utilizing the stability correction function suggested by Grachev et al. (2007) for improved weather and climate model’s predictability over mountainous environments.