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  • Long Island Sound temperature variability and its associations with the ridge–trough dipole and tropical modes of sea surface temperature variability
Title: Long Island Sound temperature variability and its associations with the ridge–trough dipole and tropical modes of sea surface temperature variability
Abstract. Possible mechanisms behind the longevity of intense Long IslandSound (LIS) water temperature events are examined using an event-basedapproach. By decomposing an LIS surface water temperature time series intonegative and positive events, it is revealed that the most intense LIS watertemperature event in the 1979–2013 period occurred around 2012, coincidingwith the 2012 ocean heat wave across the Mid-Atlantic Bight. The LIS eventsare related to a ridge–trough dipole pattern whose strength and evolution canbe determined using a dipole index. The dipole index was shown to be stronglycorrelated with LIS water temperature anomalies, explaining close to 64 %of cool-season LIS water temperature variability. Consistently, a majordipole pattern event coincided with the intense 2012 LIS warm event. Acomposite analysis revealed that long-lived intense LIS water temperatureevents are associated with tropical sea surface temperature (SST) patterns.The onset and mature phases of LIS cold events were shown to coincide withcentral Pacific El Niño events, whereas the termination of LIS coldevents was shown to possibly coincide with canonical El Niño events or ElNiño events that are a mixture of eastern and central Pacific El Niñoflavors. The mature phase of LIS warm events was shown to be associated withnegative SST anomalies across the central equatorial Pacific, though theresults were not found to be robust. The dipole pattern was also shown to berelated to tropical SST patterns, and fluctuations in central Pacific SSTanomalies were shown to evolve coherently with the dipole pattern and thestrongly related East Pacific–North Pacific pattern on decadal timescales.The results from this study have important implications for seasonal anddecadal prediction of the LIS thermal system.  more » « less
Award ID(s):
1822015
PAR ID:
10164903
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Ocean Science
Volume:
15
Issue:
1
ISSN:
1812-0792
Page Range / eLocation ID:
161 to 178
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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