Jegen, Anna Margarethe, Lange, Dietrich , Karstensen, Johannes , Pizarro, Oscar and Kopp, Heidrun (2024) Deep ocean hydrographic variability estimated from distributed geodetic sensor arrays off northern Chile. Scientific Reports, 14 . Art.Nr. 11163. DOI 10.1038/s41598-024-61929-z.

Preview	Text s41598-024-61929-z.pdf - Published Version Available under License Creative Commons: Attribution 4.0. Download (8MB) | Preview
	Text 41598_2024_61929_MOESM1_ESM.docx - Supplemental Material Available under License Creative Commons: Attribution 4.0. Download (3MB)

Abstract

Observations of spatio-temporal variability of the deep ocean are rare and little is known about occurrence of deep ocean mesoscale dynamics. Here, we make use of 2.5 years of time series data from three distributed sensor arrays, which acquired high-resolution temperature, pressure and sound speed data of the bottom layer offshore northern Chile. Estimating salinity and density from the direct observations enable access to the full spectrum of hydrographic variability from a multi-hourly to annual time scale and with average inter-station distances of less than 1 km. Analyses revealed interannual warming over the continental slope of 0.002 °C yr−1–0.003 °C yr−1, and could trace periodic hydrographic anomalies, likely related to coastal-trapped waves, as far as to the lower continental slope. A concurrent change in the shape of the warm anomalies and the rate of deep-sea warming that occurs with the crossing of the deep-sea trench suggests that the abyssal part of the eastern boundary current system off Chile does not extend past the deep sea trench. Furthermore, the comparison of anomaly timing and shape in between stations implies southwards flow over the mid to lower continental slope, centred closer to the trench.

Actions (login required)

View Item