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arXiv · 2412.14196

Investigating Central England Temperature Variability: Statistical Analysis of Associations with North Atlantic Oscillation (NAO) and Pacific Decadal Oscillation (PDO)

Abstract

This study investigates the variability of the Central England Temperature (CET) series in relation to the North Atlantic Oscillation (NAO) and the Pacific Decadal Oscillation (PDO) using advanced time series modeling techniques. Leveraging the world's longest continuous instrumental temperature dataset (1723-2023), this research applies ARIMA and ARIMAX models to quantify the impact of climatic oscillations on regional temperature variability, while also accounting for long-term warming trends. Spectral and coherence analyses further explore the periodic interactions between CET and the oscillations. Results reveal that NAO exerts a stronger influence on CET variability compared to PDO, with significant coherence observed at cycles of 5 to 7.5 years and 2 to 2.5 years for NAO, while PDO shows no statistically significant coherence. The ARIMAX model effectively captures both the upward warming trend and the influence of climatic oscillations, with robust diagnostics confirming its reliability. This study contributes to understanding the interplay between regional temperature variability and large-scale climatic drivers, providing a framework for future research on climatic oscillations and their role in shaping regional climate dynamics. Limitations and potential future directions, including the integration of additional climatic indices and comparative regional analyses, are also discussed.

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BibTeXRIS

Jiahe Ling. 2024-12-14. Investigating Central England Temperature Variability: Statistical Analysis of Associations with North Atlantic Oscillation (NAO) and Pacific Decadal Oscillation (PDO). https://arxiv.org/abs/2412.14196

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