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arXiv · 2111.14998

Harnessing expressive capacity of Machine Learning modeling to represent complex coupling of Earth's auroral space weather regimes

Abstract

We develop multiple Deep Learning (DL) models that advance the state-of-the-art predictions of the global auroral particle precipitation. We use observations from low Earth orbiting spacecraft of the electron energy flux to develop a model that improves global nowcasts (predictions at the time of observation) of the accelerated particles. Multiple Machine Learning (ML) modeling approaches are compared, including a novel multi-task model, models with tail- and distribution-based loss functions, and a spatio-temporally sparse 2D-convolutional model. We detail the data preparation process as well as the model development that will be illustrative for many similar time series global regression problems in space weather and across domains. Our ML improvements are three-fold: 1) loss function engineering; 2) multi-task learning; and 3) transforming the task from time series prediction to spatio-temporal prediction. Notably, the ML models improve prediction of the extreme events, historically obstinate to accurate specification and indicate that increased expressive capacity provided by ML innovation can address grand challenges in the science of space weather.

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Jack Ziegler, Ryan M. Mcgranaghan. 2021-11-29. Harnessing expressive capacity of Machine Learning modeling to represent complex coupling of Earth's auroral space weather regimes. https://arxiv.org/abs/2111.14998

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