Sea Level Trend and Fronts in the South Atlantic Ocean

The understanding of the physical drivers of sea level trend is crucial on global and regional scales. In particular, little is known about the sea level trend in the South Atlantic Ocean in comparison with other parts of the world. In this work, we computed the South Atlantic mean sea level (SAMSL) trend from 25 years of satellite altimetry data, and we analyzed the contributions of steric height (thermosteric and halosteric components) and ocean mass changes for the period 2005–2016 when all the source data used (Argo, GRACE and satellite altimetry) overlap. The SAMSL trend is 2.65 ± 0.24 mm/yr and is mostly explained by ocean mass trend, which is 2.22 ± 0.21 mm/yr. However, between 50° S–33° S, the steric height component constitutes the main contribution in comparison with the ocean mass component. Within that latitudinal band, three regions with trend values higher than the SAMSL trend are observed when considering 25 years of satellite SLA. In the three regions, a southward displacement of the Subtropical, Subantarctic, and Polar Fronts is observed. The southward shift of the fronts is associated with the strengthening and polar shift of westerly winds and contributes to a clear thermosteric trend that translates to the SLA trend observed in those regions.

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Constraining 20th‐Century Sea‐Level Rise in the South Atlantic Ocean

Journal of Geophysical Research Oceans ◽

10.1029/2020jc016970 ◽

2021 ◽

Vol 126 (3) ◽

Author(s):

Thomas Frederikse ◽

Surendra Adhikari ◽

Tim J. Daley ◽

Sönke Dangendorf ◽

Roland Gehrels ◽

...

Keyword(s):

Atlantic Ocean ◽

Sea Level Rise ◽

Sea Level ◽

20Th Century ◽

South Atlantic ◽

South Atlantic Ocean ◽

The South

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The impacts of Meltwater Pulse-1A in the South Atlantic Ocean deep circulation since the Last Glacial Maximum

Climate of the Past Discussions ◽

10.5194/cpd-9-6375-2013 ◽

2013 ◽

Vol 9 (6) ◽

pp. 6375-6395 ◽

Cited By ~ 1

Author(s):

J. M. Marson ◽

I. Wainer ◽

Z. Liu ◽

M. M. Mata

Keyword(s):

Atlantic Ocean ◽

Sea Level ◽

Last Glacial Maximum ◽

South Atlantic ◽

Glacial Maximum ◽

South Atlantic Ocean ◽

The South ◽

Last Glacial ◽

The Last Glacial Maximum ◽

The Last Glacial

Abstract. Since 21 000 yr ago, the oceans have received large amounts of freshwater in pulses coming from the melting ice sheets. A specific event, known as meltwater pulse 1A (MWP-1A), has been identified in sea-level and temperature proxy records as responsible for the increase of ~20 m in sea level in less than 500 yr. Although its origin and timing are still under discussion, MWP-1A seems to have had a significant impact on several components of the climatic system. The present work aims to elucidate these impacts on the water mass distribution of the South Atlantic Ocean through the analysis of a transient simulation of the climate evolution from the Last Glacial Maximum to Present Day using a state-of-art CGCM, the National Center for Atmospheric Research Community Climate System Model version 3 (NCAR CCSM3). Results show that the freshwater discharge associated with the timing of MWP-1A was crucial to establish the present thermohaline structure associated with the North Atlantic Deep Water, marking the transition between a shallower and a deeper Atlantic Meridional Overturning Circulation.

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