Generation and Transformation of Nonlinear Internal Waves in the Kara Gates Strait, Arctic Ocean

Abstract

This work examines the diverse mechanisms underlying the generation of nonlinear internal waves (NLIWs) through the complex transformation of tidal energy in the Kara Gates, a large strait at 70.5°N separating the Novaya Zemlya Archipelago from Vaygach Island and characterized by intense tidal dynamics. In situ data were acquired in summer 2023 during the “MIPT Floating University expedition” at various locations within the strait, complemented by analyses of data derived from the updated Arc2kmTM tidal model and satellite observations of the ocean surface informed by prior research. Our findings are based on a data set that is both internally consistent and indicative of distinct NLIW generation mechanisms: internal tide evolution (ITE), lee wave generation (LWG), and frontal generation (FG), which are operating in different regions of the strait and during varying phases of the spring‐neap tidal cycle. Notably, the differential genesis of short‐period oscillations results in a range of spatial and vertical characteristics, which are expected to influence mixing processes within the strait's water column. Although our study area is limited to Kara Gates Strait, we posit that analogous situations may exist in other regions, including the Arctic, as the mechanisms identified are not strictly tied to specific geographic features.