Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Tazi, Kenza, Kim, Sun Woo P., Girona-Mata, Marc, Turner, Richard E.
Format: Preprint
Veröffentlicht: 2025
Schlagworte:
Online-Zugang:https://arxiv.org/abs/2501.15690
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866909666261336064
author Tazi, Kenza
Kim, Sun Woo P.
Girona-Mata, Marc
Turner, Richard E.
author_facet Tazi, Kenza
Kim, Sun Woo P.
Girona-Mata, Marc
Turner, Richard E.
contents High Mountain Asia (HMA) holds the highest concentration of frozen water outside the polar regions, serving as a crucial water source for more than 1.9 billion people. Precipitation represents the largest source of uncertainty for future hydrological modelling in this area. In this study, we propose a probabilistic machine learning framework to combine monthly precipitation from 13 regional climate models developed under the Coordinated Regional Downscaling Experiment (CORDEX) over HMA via a mixture of experts (MoE). This approach accounts for seasonal and spatial biases within the models, enabling the prediction of more faithful precipitation distributions. The MoE is trained and validated against gridded historical precipitation data, yielding 32% improvement over an equally-weighted average and 254% improvement over choosing any single ensemble member. This approach is then used to generate precipitation projections for the near future (2036-2065) and far future (2066-2095) under RCP4.5 and RCP8.5 scenarios. Compared to previous estimates, the MoE projects wetter summers but drier winters over the western Himalayas and Karakoram and wetter winters over the Tibetan Plateau, Hengduan Shan, and South East Tibet.
format Preprint
id arxiv_https___arxiv_org_abs_2501_15690
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Refined climatologies of future precipitation over High Mountain Asia using probabilistic ensemble learning
Tazi, Kenza
Kim, Sun Woo P.
Girona-Mata, Marc
Turner, Richard E.
Atmospheric and Oceanic Physics
Machine Learning
High Mountain Asia (HMA) holds the highest concentration of frozen water outside the polar regions, serving as a crucial water source for more than 1.9 billion people. Precipitation represents the largest source of uncertainty for future hydrological modelling in this area. In this study, we propose a probabilistic machine learning framework to combine monthly precipitation from 13 regional climate models developed under the Coordinated Regional Downscaling Experiment (CORDEX) over HMA via a mixture of experts (MoE). This approach accounts for seasonal and spatial biases within the models, enabling the prediction of more faithful precipitation distributions. The MoE is trained and validated against gridded historical precipitation data, yielding 32% improvement over an equally-weighted average and 254% improvement over choosing any single ensemble member. This approach is then used to generate precipitation projections for the near future (2036-2065) and far future (2066-2095) under RCP4.5 and RCP8.5 scenarios. Compared to previous estimates, the MoE projects wetter summers but drier winters over the western Himalayas and Karakoram and wetter winters over the Tibetan Plateau, Hengduan Shan, and South East Tibet.
title Refined climatologies of future precipitation over High Mountain Asia using probabilistic ensemble learning
topic Atmospheric and Oceanic Physics
Machine Learning
url https://arxiv.org/abs/2501.15690