arXiv Machine Learning By Shunya Nagashima, Takumi Bannai

Scale-Recursive Rectified Flows for Few-Step Precipitation Ensembles

Read the original on arXiv Machine Learning →

The paper introduces a scale‑recursive rectified flow that first generates broad rainfall patterns and then refines local details, allocating sampling steps based on ensemble variability and prediction error across spatial scales. This approach reduces the number of sampling steps while maintaining ensemble diversity, improving probabilistic accuracy and rain detection in satellite‑to‑radar downscaling over the United States. The method outperforms a non‑recursive flow with more steps, achieving better accuracy in less time.

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