Detecting Climate Teleconnections With Granger Causality. Issue 18 (14th September 2021)

• Record Type: Journal Article
• Authors: Silva, Filipi N.; Vega‐Oliveros, Didier A.; Yan, Xiaoran; Flammini, Alessandro; Menczer, Filippo; Radicchi, Filippo; Kravitz, Ben; Fortunato, Santo
• Is Part Of: Geophysical research letters. Volume 48:Issue 18(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-09-14
• Subjects: teleconnections -- ENSO -- Granger causality; Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1029/2021GL094707
• Languages: English
• ISSNs: 0094-8276

Abstract

Abstract: Climate system teleconnections are crucial for improving climate predictability, but difficult to quantify. Standard approaches to identify teleconnections are often based on correlations between time series. Here we present a novel method leveraging Granger causality, which can infer/detect relationships between any two fields. We compare teleconnections identified by correlation and Granger causality at different timescales. We find that both Granger causality and correlation consistently recover known seasonal precipitation responses to the sea surface temperature pattern associated with the El Niño Southern Oscillation. Such findings are robust across multiple time resolutions. In addition, we identify candidates for unexplored teleconnection responses. Plain Language Summary: Teleconnections, or climate responses far away from a perturbation, are difficult to study. We have developed a new method of quantifying teleconnection strengths and identifying new teleconnections. When testing this method on global precipitation responses to El Niño surface temperature changes, not only does our method do a good job of recovering previous findings, but we identify several new possible teleconnections. Our method can be applied to any two climate variables and could be useful for attribution studies, for example changes in frequency of extreme events. Key Points: We propose a new method for identifying significant teleconnections between any two climate fields We test this method on Niño 3.4 temperature teleconnections to precipitation anomalies everywhere The method recovers previously known El Niño teleconnections and discovers potential new ones