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Learning Coupled Earth System Dynamics with GraphDOP

Boucher, Eulalie, Alexe, Mihai, Lean, Peter, Pinnington, Ewan, Lang, Simon, Laloyaux, Patrick, Zampieri, Lorenzo, de Rosnay, Patricia, Bormann, Niels, McNally, Anthony

arXiv.org Artificial Intelligence

Interactions between different components of the Earth System (e.g. ocean, atmosphere, land and cryosphere) are a crucial driver of global weather patterns. Modern Numerical Weather Prediction (NWP) systems typically run separate models of the different components, explicitly coupled across their interfaces to additionally model exchanges between the different components. Accurately representing these coupled interactions remains a major scientific and technical challenge of weather forecasting. GraphDOP is a graph-based machine learning model that learns to forecast weather directly from raw satellite and in-situ observations, without reliance on reanalysis products or traditional physics-based NWP models. GraphDOP simultaneously embeds information from diverse observation sources spanning the full Earth system into a shared latent space. This enables predictions that implicitly capture cross-domain interactions in a single model without the need for any explicit coupling. Here we present a selection of case studies which illustrate the capability of GraphDOP to forecast events where coupled processes play a particularly key role. These include rapid sea-ice freezing in the Arctic, mixing-induced ocean surface cooling during Hurricane Ian and the severe European heat wave of 2022. The results suggest that learning directly from Earth System observations can successfully characterise and propagate cross-component interactions, offering a promising path towards physically consistent end-to-end data-driven Earth System prediction with a single model.


COPU: Conformal Prediction for Uncertainty Quantification in Natural Language Generation

Wang, Sean, Jiang, Yicheng, Tang, Yuxin, Cheng, Lu, Chen, Hanjie

arXiv.org Artificial Intelligence

Uncertainty Quantification (UQ) for Natural Language Generation (NLG) is crucial for assessing the performance of Large Language Models (LLMs), as it reveals confidence in predictions, identifies failure modes, and gauges output reliability. Conformal Prediction (CP), a model-agnostic method that generates prediction sets with a specified error rate, has been adopted for UQ in classification tasks, where the size of the prediction set indicates the model's uncertainty. However, when adapting CP to NLG, the sampling-based method for generating candidate outputs cannot guarantee the inclusion of the ground truth, limiting its applicability across a wide range of error rates. To address this, we propose \ourmethod, a method that explicitly adds the ground truth to the candidate outputs and uses logit scores to measure nonconformity. Our experiments with six LLMs on four NLG tasks show that \ourmethod outperforms baseline methods in calibrating error rates and empirical cover rates, offering accurate UQ across a wide range of user-specified error rates.


Synergy between Observation Systems Oceanic in Turbulent Regions

Nguyen, Van-Khoa, Agudelo, Santiago

arXiv.org Artificial Intelligence

Ocean dynamics constitute a source of incertitude in determining the ocean's role in complex climatic phenomena. Current observation systems have difficulty achieving sufficiently statistic precision for three-dimensional oceanic data. It is crucial knowledge to describe the behavior of internal ocean structures. We present a data-driven approach that explores latent class regressions and deep neural networks in modeling ocean dynamics in the extensions of Gulf Stream and Kuroshio currents. The obtained results show a promising direction of data-driven for understanding the ocean's characteristics (salinity, temperature) in both spatial and temporal dimensions in the turbulent regions. Our source codes are publicly available at https://github.com/v18nguye/gulfstream-lrm and at https://github.com/sagudelor/Kuroshio.


Coarse-grain Fine-grain Coattention Network for Multi-evidence Question Answering

Zhong, Victor, Xiong, Caiming, Keskar, Nitish Shirish, Socher, Richard

arXiv.org Artificial Intelligence

End-to-end neural models have made significant progress in question answering, however recent studies show that these models implicitly assume that the answer and evidence appear close together in a single document. In this work, we propose the Coarse-grain Fine-grain Coattention Network (CFC), a new question answering model that combines information from evidence across multiple documents. The CFC consists of a coarse-grain module that interprets documents with respect to the query then finds a relevant answer, and a fine-grain module which scores each candidate answer by comparing its occurrences across all of the documents with the query. We design these modules using hierarchies of coattention and self-attention, which learn to emphasize different parts of the input. On the Qangaroo WikiHop multi-evidence question answering task, the CFC obtains a new state-of-the-art result of 70.6% on the blind test set, outperforming the previous best by 3% accuracy despite not using pretrained contextual encoders.


Global warming in Alaska tricked computer to DELETE data

Daily Mail - Science & tech

Temperatures in the Arctic have been rising so fast in recent decades they have confused a computer designed to measure them. Scientists monitoring a site in Alaska have found that an algorithm at the weather station, which has been recording temperatures for nearly 100 years, deleted all of its data from 2017, and even some from 2016. In what the experts are now calling an'ironic exclamation point' to rapid climate change, the algorithm flagged the abnormal temperatures observed at the station, as it assumed they were too high to be accurate. When scientists set out at the beginning of December to review the previous month's climate data, they noticed something'odd': everything from Utqiaġvik, Alaska was missing. The data from 2017 and some of 2016 had been flagged as artificial.


Video Solves Mystery of How Narwhals Use Their Tusks

National Geographic

Video shows how narwhals use their iconic tusks to hunt fish. Filmed near Nunavut, Canada, a narwhal can be seen tapping a fish with its tusk. The unicorn of the sea just got a little less mysterious. Until now, how narwhals used their long tusks had been subject to much speculation by scientists. Behavior captured for the first time on camera shows narwhals using the long tusks protruding from their heads to stun Arctic cod by hitting them, using jagged, quick movements.