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Title: Simulating the role of surface forcing on observed multidecadal upper-ocean salinity changes

Journal Article · · Journal of Climate
 [1];  [2];  [3];  [2];  [4];  [5]
  1. CSIRO, Oceans and Atmosphere, Hobart (Australia). Centre for Australian Weather and Climate Research; Univ. of Tasmania, Hobart (Australia). Institute for Marine and Antarctic Studies
  2. CSIRO, Oceans and Atmosphere, Hobart (Australia). Centre for Australian Weather and Climate Research
  3. CSIRO, Oceans and Atmosphere, Hobart (Australia). Centre for Australian Weather and Climate Research; Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Program for Climate Model Diagnosis and Intercomparison
  4. CSIRO, Oceans and Atmosphere, Hobart (Australia). Centre for Australian Weather and Climate Research; Univ. of Tasmania, Hobart (Australia). Institute for Marine and Antarctic Studies; Antarctic Climate and Ecosystems Cooperative Research Centre, Hobart (Australia)
  5. CSIRO Oceans and Atmosphere Flagship, Victoria (Australia). Centre for Australian Weather and Climate Research

The ocean’s surface salinity field has changed over the observed record, driven by an intensification of the water cycle in response to global warming. However, the origin and causes of the coincident subsurface salinity changes are not fully understood. The relationship between imposed surface salinity and temperature changes and their corresponding subsurface changes is investigated using idealized ocean model experiments. The ocean’s surface has warmed by about 0.5°C (50 yr)–1 while the surface salinity pattern has amplified by about 8% per 50 years. The idealized experiments are constructed for a 50-yr period, allowing a qualitative comparison to the observed salinity and temperature changes previously reported. The comparison suggests that changes in both modeled surface salinity and temperature are required to replicate the three-dimensional pattern of observed salinity change. The results also show that the effects of surface changes in temperature and salinity act linearly on the changes in subsurface salinity. In addition, surface salinity pattern amplification appears to be the leading driver of subsurface salinity change on depth surfaces; however, surface warming is also required to replicate the observed patterns of change on density surfaces. This is the result of isopycnal migration modified by the ocean surface warming, which produces significant salinity changes on density surfaces.

Research Organization:
Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
Sponsoring Organization:
USDOE
Grant/Contract Number:
AC52-07NA27344
OSTI ID:
1305857
Report Number(s):
LLNL-JRNL-677101
Journal Information:
Journal of Climate, Vol. 29, Issue 15; ISSN 0894-8755
Publisher:
American Meteorological SocietyCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 28 works
Citation information provided by
Web of Science

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Cited By (3)

Examining the salinity change in the upper Pacific Ocean during the Argo period journal August 2019
Salt Sinking in the Upper South Pacific Subtropical Gyre From 2004 to 2016 journal October 2019
Halosteric Sea Level Changes during the Argo Era journal July 2017

Figures / Tables (10)