Work

Estimating Downward Shortwave Radiation over Complex Terrain: Synergizing Sentinel-2 Imagery and Topographic Data via Physics-Guided XGBoost

Year: 2026

Type: article

Abstract: Downward shortwave radiation (DSR) varies strongly across mountain slopes, and products designed for horizontal surfaces may not resolve this variability. We estimated slope-parallel DSR at eight Saihanba sites using Sentinel-2 imagery, topography, atmospheric inputs, and BRDF-informed surface albedo. Both branches used XGBoost, with the clear-sky branch further incorporating a parameterized radiation anchor, bounded residual learning, and support-aware output correction. On the 2024 test set (n = 1451), the full framework achieved an RMSE of 92.60 W/m2, an NRMSE of 15.79% and an R2 of 0.897. Pooled leave-one-site-out validation across all 6096 samples yielded an RMSE of 113.68 W/m2. For horizontal-surface observations at 10 Heihe River Basin stations, NRMSE was 17.60%. Clear-sky estimates depended most on solar-incidence geometry, whereas top-of-atmosphere spectra dominated the cloudy-sky XGBoost model.

Source: Remote Sensing

DOI: 10.3390/rs18203483

Authors: Zhanjie Qi, Xiuping Xie, Jianrong Cao, Ke Zheng, Wenhui Xie

Institution: Liaocheng University

Language: English

Topic: Solar Radiation and Photovoltaics

Subfield: Artificial Intelligence

Field: Computer Science

Domain: Physical Sciences

SDG: Climate action

Open Access status: gold

Estimated APC paid: $3,258