Papers for

hydrological planners

Papers whose findings have a practical use for this group, as judged from the abstract. Open a paper to read what it means in practice.

U-Net and GAN models improve rainfall detail over West Africa

Statistical Downscaling of Daily Precipitation from ERA5 Atmospheric Fields to IMERG over West Africa

Abstract: Global reanalyses are too coarse to resolve the convective systems that produce most West African monsoon rainfall. In this work, we use U-Net based architectures to downscale daily ERA5 fields (0.25°) to IMERG V07 satellite precipitation (0.1°) over West Africa for the June to October seasons of 2000 to 2024, using geopotential, temperature, humidity and wind at three pressure levels together with elevation and land fraction. Adding ERA5 precipitation as input slightly improves performance for this particular challenging region. We find that all the deterministic networks investigated for this work are too dry and lose almost all observed variance below a few hundred kilometers, which motivated our use of a GAN-based alternative. We also investigated permutation importance for the U-Net that ranks 500 hPa specific humidity first, consistent with the sensitivity of deep convection to mid-tropospheric moisture.

Mon 12 OctMachine Learning

The gist

Weather forecasts over West Africa struggle to capture the small storms that cause most rain because the data is too coarse. The authors used advanced computer models called U-Net and GAN to transform rough weather data into much finer rain maps for daily rainfall. They found that standard models miss a lot of rain variability nearby, so they added a special GAN model to do better. They also discovered that moisture around 500 hPa altitude is the most important factor for predicting rain in this region.

Open → 2610.16816v1