CLLMate: A Multimodal Benchmark for Weather and Climate Events Forecasting

Haobo Li, Zhaowei Wang, Jiachen Wang, Yueya Wang, Alexis Kai Hon Lau, Huamin Qu


Abstract
Forecasting weather and climate events is crucial for making appropriate measures to mitigate environmental hazards and minimize losses. However, existing environmental forecasting research focuses narrowly on predicting numerical meteorological variables (e.g., temperature), neglecting the translation of these variables into actionable textual narratives of events and their consequences. To bridge this gap, we proposed Weather and Climate Event Forecasting (WCEF), a new task that leverages numerical meteorological raster data and textual event data to predict weather and climate events. This task is challenging to accomplish due to difficulties in aligning multimodal data and the lack of supervised datasets. To address these challenges, we present CLLMate, the first multimodal dataset for WCEF, using 26,156 environmental news articles aligned with ERA5 reanalysis data. We systematically benchmark 32 existing models on CLLMate, including closed-source, open-source, and our fine-tuned models. Our experiments reveal the advantages and limitations of existing MLLMs and the value of CLLMate for the training and benchmarking of the WCEF task. The dataset is available at https://github.com/hobolee/CLLMate.
Anthology ID:
2025.emnlp-main.886
Volume:
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
Month:
November
Year:
2025
Address:
Suzhou, China
Editors:
Christos Christodoulopoulos, Tanmoy Chakraborty, Carolyn Rose, Violet Peng
Venue:
EMNLP
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Publisher:
Association for Computational Linguistics
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Pages:
17547–17573
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URL:
https://preview.aclanthology.org/ingest-emnlp/2025.emnlp-main.886/
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Cite (ACL):
Haobo Li, Zhaowei Wang, Jiachen Wang, Yueya Wang, Alexis Kai Hon Lau, and Huamin Qu. 2025. CLLMate: A Multimodal Benchmark for Weather and Climate Events Forecasting. In Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing, pages 17547–17573, Suzhou, China. Association for Computational Linguistics.
Cite (Informal):
CLLMate: A Multimodal Benchmark for Weather and Climate Events Forecasting (Li et al., EMNLP 2025)
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