The effect of the equatorial Pacific cold SST bias on simulated ENSO teleconnections to the North Pacific and California

Bayr, Tobias, Domeisen, Daniela I.V. and Wengel, Christian (2019) The effect of the equatorial Pacific cold SST bias on simulated ENSO teleconnections to the North Pacific and California Climate Dynamics, 53 (7-8). pp. 3771-3789. DOI 10.1007/s00382-019-04746-9.

[img] Text
Bayr2019_Article_TheEffectOfTheEquatorialPacifi.pdf - Published Version
Restricted to Registered users only

Download (3692Kb) | Contact

Supplementary data:

Abstract

Precipitation in California is modulated by variability in the tropical Pacific associated with El Nino/Southern Oscillation (ENSO): more rainfall is expected during El Nino episodes, and reduced rainfall during La Nina. It has been suggested that besides the shape and location of the sea surface temperature ( SST) anomaly this remote connection depends on the strength and location of the atmospheric convection response in the tropical Pacific. Here we show in a perturbed physics ensemble of the Kiel Climate Model and CMIP5 models that due to a cold equatorial SST bias many climate models are in a La Nina-like mean state, resulting in a too westward position of the rising branch of the Pacific Walker Circulation. This in turn results in a convective response along the equator during ENSO events that is too far west in comparison to observations. This effect of the equatorial cold SST bias is not restricted to the tropics, moreover it leads to a too westward SLP response in the North Pacific and too westward precipitation response that does not reach California. Further we show that climate models with a reduced equatorial cold SST bias have a more realistic representation of the spatial asymmetry of the teleconnections between El Nino and La Nina.

Document Type: Article
Keywords: El Nino/Southern Oscillation; Sea surface temperature bias; North Pacific teleconnections; Rainfall over California; Perturbed physics ensemble; CMIP5
Research affiliation: OceanRep > GEOMAR > FB1 Ocean Circulation and Climate Dynamics > FB1-ME Maritime Meteorology
OceanRep > SFB 754
Refereed: Yes
DOI etc.: 10.1007/s00382-019-04746-9
ISSN: 0930-7575
Projects: SACUS, SFB754
Expeditions/Models:
Date Deposited: 11 Nov 2019 13:03
Last Modified: 11 Nov 2019 13:03
URI: http://eprints.uni-kiel.de/id/eprint/48213

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...