@article{aad8e2b80ab9498682bcfeaf2499248c,
title = "Teleconnection between the Atlantic meridional overturning circulation and sea level in the Mediterranean Sea",
abstract = "The Mediterranean Sea can be viewed as a {"}barometer{"} of the North Atlantic Ocean, because its sea level responds to oceanic-gyre-scale changes in atmospheric pressure and wind forcing, related to the North Atlantic Oscillation (NAO). The climate of the North Atlantic is influenced by the Atlantic meridional overturning circulation (AMOC) as it transports heat from the South Atlantic toward the subpolar North Atlantic. This study reports on a teleconnection between the AMOC transport measured at 26.5°N and the Mediterranean Sea level during 2004-17: a reduced/increased AMOC transport is associated with a higher/lower sea level in the Mediterranean. Processes responsible for this teleconnection are analyzed in detail using available satellite and in situ observations and an atmospheric reanalysis. First, it is shown that on monthly to interannual time scales the AMOC and sea level are both driven by similar NAO-like atmospheric circulation patterns. During a positive/negative NAO state, stronger/weaker trade winds (i) drive northward/southward anomalies of Ekman transport across 26.5°N that directly affect the AMOC and (ii) are associated with westward/eastward winds over the Strait of Gibraltar that force water to flow out of/into the Mediterranean Sea and thus change its average sea level. Second, it is demonstrated that interannual changes in the AMOC transport can lead to thermosteric sea level anomalies near the North Atlantic eastern boundary. These anomalies can (i) reach the Strait of Gibraltar and cause sea level changes in the Mediterranean Sea and (ii) represent a mechanism for negative feedback on the AMOC.",
keywords = "Mediterranean Sea, Meridional overturning circulation, North Atlantic Ocean, Ocean dynamics, Oceanic variability, Sea level",
author = "Volkov, {Denis L.} and Molly Baringer and David Smeed and William Johns and Landerer, {Felix W.}",
note = "Funding Information: Acknowledgments. This work was supported by the NASA Ocean Surface Topography Science Team program (via Grant NNX13AO73G) and by the National Oceanic and Atmospheric Administration (NOAA) Atlantic Oceanographic and Meteorological Laboratory, and it was carried out in part under the auspices of the Cooperative Institute of Marine and Atmospheric Studies (CIMAS) of the University of Miami and NOAA, Cooperative Agreement NA10OAR4320143. D. Smeed was supported by the EU Horizons 2020 project AtlantOs (Grant 633211). A portion of this research (F. Landerer) was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. The satellite altimetry data are processed and distributed by CMEMS (http://marine.copernicus.eu). Data from the RAPID– MOC/MOCHA/WBTS MOC monitoring array are jointly funded by the U.K. Natural Environment Research Council, the National Science Foundation, and NOAA; the 12-hourly MOC data are made freely available online (www.rapid.ac.uk/rapidmoc and www. rsmas.miami.edu/users/mocha). The 26.5°N MOC array and Argo program are part of the Global Ocean Observing System. The Argo data were collected and made freely available by the International Argo Program and the national programs that contribute to it (http://www. argo.ucsd.edu, http://argo.jcommops.org). The monthly station-based NAO index was retrieved online (https:// climatedataguide.ucar.edu/climate-data/hurrell-north-atlantic-oscillation-nao-index-station-based). The authors thank Drs. Sang-Ki Lee and Chris Hughes and an anonymous reviewer for useful comments and suggestions on the initial version of the manuscript. Funding Information: This work was supported by the NASA Ocean Surface Topography Science Team program (via Grant NNX13AO73G) and by the National Oceanic and Atmospheric Administration (NOAA) Atlantic Oceanographic and Meteorological Laboratory, and it was carried out in part under the auspices of the Cooperative Institute of Marine and Atmospheric Studies (CIMAS) of the University of Miami and NOAA, Cooperative Agreement NA10OAR4320143. D. Smeed was supported by the EU Horizons 2020 project AtlantOs (Grant 633211). A portion of this research (F. Landerer) was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. The satellite altimetry data are processed and distributed by CMEMS (http://marine.copernicus.eu). Data from the RAPID-MOC/MOCHA/WBTS MOC monitoring array are jointly funded by the U.K. Natural Environment Research Council, the National Science Foundation, and NOAA; the 12-hourly MOC data are made freely available online (www.rapid.ac.uk/rapidmoc and www. rsmas.miami.edu/users/mocha). The 26.58N MOC array and Argo program are part of the Global Ocean Observing System. The Argo data were collected and made freely available by the International Argo Program and the national programs that contribute to it (http://www. argo.ucsd.edu, http://argo.jcommops.org). The monthly station-based NAO index was retrieved online (https:// climatedataguide.ucar.edu/climate-data/hurrell-northatlantic-oscillation-nao-index-station-based). The authors thank Drs. Sang-Ki Lee and Chris Hughes and an anonymous reviewer for useful comments and suggestions on the initial version of the manuscript. Publisher Copyright: {\textcopyright} 2019 American Meteorological Society.",
year = "2019",
month = feb,
day = "1",
doi = "10.1175/JCLI-D-18-0474.1",
language = "English (US)",
volume = "32",
pages = "935--955",
journal = "Journal of Climate",
issn = "0894-8755",
publisher = "American Meteorological Society",
number = "3",
}