Warming Trend in Antarctic Bottom Water in the Vema Channel in the South Atlanti

Published in Geophysical Research Letters, 48, e2021GL094709.
Authors

Campos, E. J. D., van Caspel, M. C., Zenk, W., Morozov, E. G., Frey, D. I., Piola, A. R., et al. (2021). 

Correspondence to:
E. J. D. Campos,
edmo@usp.br

Publication year 2021
DOI https://doi.org/10.1029/2021GL094709
Affiliations

1Oceanographic Institute of the University of São Paulo, Sao Paulo, Brazil, 2College of Arts and Sciences, American University of Sharjah, Sharjah, United Arab Emirates, 3Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforchung, Bremerhaven, Germany, 4GEOMAR Helmholtz Centre for Ocean Research, Kiel, Germany, 5Shirshov Institute of Oceanology, Moscow, Russia, 6Servício de Hidrografia Naval, Buenos Aires, Argentina, 7Universidad de Buenos Aires, Buenos Aires, Argentina, 8Atlantic Oceanographic and Meteorological Laboratory, NOAA, Miami, FL, USA

Edmo J. D. Campos1,2 , Mathias C. van Caspel1,3, Walter Zenk4, Eugene G. Morozov5 ,Dmitry I. Frey5 , Alberto R. Piola6,7 , Christopher S. Meinen8 , Olga T. Sato1, Renellys C. Perez8 , and Shenfu Dong8

IAI Program

CRN3

IAI Project crn3070
Keywords
PDFCRN3070_Campos_Vema_2021.pdf

Highlights

• Antarctic Bottom Water (AABW) temperatures in the Vema Channel are highly variable
• AABW in the Vema Channel has been warming since the early 1970s
• Warming rate in AABW in the Vema Channel waters may be increasing

Abstract

The excess heat absorbed from the atmosphere has increased the temperature in the upper layers of the ocean (<2,000 m). In the abyss, infrequently repeated ship sections, deep Argo float measurements, and sparse moored observations have found signs of warming in the Southwest Atlantic, possibly linked to changes in the Weddell Sea. We present a new moored temperature time series sampled near the bottom in the Vema Channel, from February 2019 to August 2020. Together with historical data, the combined record confirms the warming of the abyssal waters, with an increase of 0.059°C in potential temperature between January 1991 and August 2020, embedded within intense high-frequency variability. Moreover, the data suggest the possibility of an accelerated warming, with a change in the temperature trend from 0.0016°C yr&minus1, between the early 1990s and 2005, to 0.0026°C yr&minus1 afterwards.