Transport and heat loss of the Pacific Summer Water in the Arctic Chukchi Sea northern slope: Mooring data analysis

Abstract

We investigated the transport and heat loss of the Pacific Summer Water (PSW) along the Chukchi Sea northern slope using the temperature, salinity, and velocity data of the mooring time series obtained in 2003–2005 (Period 1) and 2015–2019 (Period 2). The PSW at Stations HSN/NHC on the Chukchi Sea northern slope was warmer and fresher in Period 2 than in Period 1. Results from a lag correlation analysis of the temperature time series provide quantitative evidence to suggest that the PSW was transported from Barrow Canyon to Stations HSN/NHC by the northwestward Chukchi Slope Current. The advection time was 7–61days in the layer of 30–60 m. The temperature and salinity mostly decreased during PSW transport. Vertical mixing with the surface cold water could be a potential factor for temperature decrease. This decrease in Period 2 were higher than that in Period 1. This large decrease was probably influenced by stratification rather than wind conditions.