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The interannual‐to‐decadal variability of sea surface temperature and height in the North Atlantic exhibits a tripolar pattern. Here, we explore the spatiotemporal structure, including the vertical, of the North Atlantic tripole using observations and reanalysis data in 1993–2021. For the first time, we demonstrate that the tripole's vertical structure across the Mid‐Atlantic Bight continental shelf and slope differs from that in the ocean interior. The tripole strongly projects in the Slope Water north of the Gulf Stream mean path, marked with temperature changes across the water column not maintained by air‐sea heat flux. Over the shelf, the tripole‐associated sea level, temperature, and ocean current are weak. In the ocean interior, the tripole temperature variability is apparent in the upper 100 m in the tropics and three times as deep in the subtropics. The tripole imprints resemble those of the North Atlantic Oscillation, peaking after the dominant atmospheric mode's winter maximum. Plain Language Summary: A significant fraction of large‐scale and year‐to‐year sea surface temperature and height changes in the North Atlantic exhibit a tripolar pattern, with anomalies of the equal sign in the tropical and subpolar regions and the opposite in the subtropics. The tripolar pattern has been linked to increased nuisance flooding along the United States Southeast coast in the recent decade. Despite its extensive impacts on the low‐lying coastal lands, many of the pattern's properties remain unknown, particularly the vertical structure. This study uses long‐term observations and reanalysis data to describe tripole characteristics from the continental shelf to the ocean interior. The results indicate that the tripole‐associated temperature, sea level, and ocean current are most pronounced between the Gulf Stream and the Mid‐Atlantic Bight shelf break, concomitant with changes in the strength and position of the flow, but they rapidly decay toward the shore. In the interior, the temperature difference between the tropics and the subtropics attributable to the tripole is largest in the upper 100 m. The tripole generally attains maximum following the North Atlantic Oscillation's winter peak. Key Points: The tripole variability is strongest in the Slope WaterThe vertical extent of tripole‐related temperature variability in the subtropics is three times deeper than in the tropicsTripole‐associated temperature, ocean current, and sea level changes in the Mid‐Atlantic Bight shelf are small [ABSTRACT FROM AUTHOR] |
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