Revisiting the cause of the eastern equatorial Atlantic cold event in 2009.

Burmeister, Kristin , Brandt, Peter and Lübbecke, Joke F. (2016) Revisiting the cause of the eastern equatorial Atlantic cold event in 2009. Open Access Journal of Geophysical Research: Oceans, 121 (7). pp. 4777-4789. DOI 10.1002/2016JC011719.

[thumbnail of Burmeister_et_al_10.1002_2016JC011719.pdf]
Preview
Text
Burmeister_et_al_10.1002_2016JC011719.pdf - Published Version

Download (2MB) | Preview
[thumbnail of jgrc21802-sup-0001-2016JC011719-s01.pdf]
Preview
Text
jgrc21802-sup-0001-2016JC011719-s01.pdf - Supplemental Material

Download (504kB) | Preview

Supplementary data:

Abstract

An extreme cold sea surface temperature event occurred in the Atlantic cold tongue region in boreal summer 2009. It was preceded by a strong negative Atlantic meridional mode event associated with north-westerly wind anomalies along the equator from March to May. Although classical equatorial wave dynamics suggest that westerly wind anomalies should be followed by a warming in the eastern equatorial Atlantic, an abrupt cooling took place. In the literature two mechanisms—meridional advection of subsurface temperature anomalies and planetary wave reflection—are discussed as potential causes of such an event. Here, for the first time we use in situ measurements in addition to satellite and reanalysis products to investigate the contribution of both mechanisms to the 2009 cold event. Our results suggest that meridional advection is less important in cold events than in corresponding warm events, and, in particular, did not cause the 2009 cold event. Argo float data confirm previous findings that planetary wave reflection contributed to the onset of the 2009 cold event. Additionally, our analysis suggests that higher baroclinic modes were involved.

Document Type: Article
Funder compliance: info:eu-repo/grantAgreement/EC/FP7/603521
Keywords: Atlantic cold tongue; Atlantic zonal mode; Atlantic meridional mode; planetary wave reflection; meridional advection
Research affiliation: OceanRep > GEOMAR > FB1 Ocean Circulation and Climate Dynamics > FB1-PO Physical Oceanography
OceanRep > SFB 754
Kiel University
Refereed: Yes
Open Access Journal?: No
Publisher: AGU (American Geophysical Union), Wiley
Projects: SFB754, SACUS, RACE, PREFACE
Expeditions/Models/Experiments:
Date Deposited: 13 Jul 2016 09:40
Last Modified: 19 May 2021 09:53
URI: https://oceanrep.geomar.de/id/eprint/33355

Actions (login required)

View Item View Item