scholarly journals Atmosphere-ocean dynamics of persistent cold states of the tropical Pacific Ocean

2021 ◽  
pp. 1-44
Author(s):  
Richard Seager ◽  
Naomi Henderson ◽  
Mark Cane ◽  
Honghai Zhang ◽  
Jennifer Nakamura
Keyword(s):  
Heat Flux ◽  
Pacific Ocean ◽  
Wind Stress ◽  
Tropical Pacific ◽  
Ocean Dynamics ◽  
Dynamical Response ◽  
Thermocline Depth ◽  
Tropical Pacific Ocean ◽  
Flux Divergence ◽  
The Tropical Pacific

AbstractPersistent multiyear cold states of the tropical Pacific Ocean drive hydroclimate anomalies worldwide, including persistent droughts in the extratropical Americas. Here, the atmosphere and ocean dynamics and thermodynamics of multiyear cold states of the tropical Pacific Ocean are investigated using European Centre for Medium-Range Weather Forecasts reanalyses and simplified models of the ocean and atmosphere. The cold states are maintained by anomalous ocean heat flux divergence and damped by increased surface heat flux from the atmosphere to ocean. The anomalous ocean heat flux divergence is contributed to by both changes in the ocean circulation and thermal structure. The keys are an anomalously shallow thermocline that enhances cooling by upwelling and anomalous westward equatorial currents that enhance cold advection. The thermocline depth anomalies are shown to be a response to equatorial wind stress anomalies. The wind stress anomalies are shown to be a simple dynamical response to equatorial SST anomalies as mediated by precipitation anomalies. The cold states are fundamentally maintained by atmosphere-ocean coupling in the equatorial Pacific. The physical processes that maintain the cold states are well approximated by linear dynamics for ocean and atmosphere and simple thermodynamics.

Dynamical Response of the Tropical Pacific Ocean to Solar Forcing During the Early Holocene

Science ◽  
2010 ◽  
Vol 330 (6009) ◽  
pp. 1378-1381 ◽  
Author(s):  
T. M. Marchitto ◽  
R. Muscheler ◽  
J. D. Ortiz ◽  
J. D. Carriquiry ◽  
A. van Geen
Keyword(s):  
Pacific Ocean ◽  
Tropical Pacific ◽  
Early Holocene ◽  
Dynamical Response ◽  
Tropical Pacific Ocean ◽  
Solar Forcing ◽  
The Tropical Pacific

scholarly journals Reconstructing the Past Wind Stresses over the Tropical Pacific Ocean from 1875 to 1947

2009 ◽  
Vol 48 (6) ◽  
pp. 1181-1198 ◽  
Author(s):  
Ziwang Deng ◽  
Youmin Tang
Keyword(s):  
Pacific Ocean ◽  
Climate Variability ◽  
Regression Model ◽  
Wind Stress ◽  
Tropical Pacific ◽  
Tropical Pacific Ocean ◽  
The Past ◽  
Past Climate Variability ◽  
The Tropical Pacific

Abstract An important step in understanding the climate system is simulating and studying the past climate variability, using oceanic models, atmospheric models, or both. Toward this goal, long-term wind stress data, as the forcing of oceanic or climate models, are often required. In this study, the possibility of reconstructing the past winds of the tropical Pacific Ocean using historical sea surface temperature (SST) and sea level pressure (SLP) datasets was explored. Four statistical models, based on principal component (PC) regression and singular vector decomposition (SVD), were developed for reconstructing monthly pseudo wind stress over the tropical Pacific for the period 1875–1947. The high-frequency noise was removed from the raw data prior to the reconstruction. These models are SST-based PC regression (model 1), SLP-based PC regression (model 2), SST-based SVD (model 3), and SLP-based SVD (model 4). The results show that reconstructed wind stresses from all models can account for more than one-half of the total variances. In general, the SLP is better than SST as a predictor and the SVD method is superior to the PC regression. Forced by these reconstructed wind stresses, an oceanic general circulation model can simulate realistic interannual variability of the tropical Pacific SST. However, the wind stress reconstructed by SST-based models leads to better simulation skill in comparison with that from SLP-based models. Last, a long-term wind stress dataset was constructed for the period from 1875 to 1947 by the SST-based SVD model, which provides a useful tool for studying the past climate variability over the tropical Pacific, especially for El Niño–Southern Oscillation.

A Comparison of Climate Prediction and Simulation over the Tropical Pacific

2008 ◽  
Vol 21 (14) ◽  
pp. 3601-3611 ◽  
Author(s):  
Vasubandhu Misra ◽  
L. Marx ◽  
M. Fennessy ◽  
B. Kirtman ◽  
J. L. Kinter
Keyword(s):  
Pacific Ocean ◽  
Climate Model ◽  
Coupled Model ◽  
Tropical Pacific ◽  
Ocean Dynamics ◽  
Upper Ocean ◽  
Model Errors ◽  
Tropical Pacific Ocean ◽  
Operating Modes ◽  
The Tropical Pacific

Abstract This study compares an ensemble of seasonal hindcasts with a multidecadal integration from the same global coupled climate model over the tropical Pacific Ocean. It is shown that the annual mean state of the SST and its variability are different over the tropical Pacific Ocean in the two operating modes of the model. These differences are symptoms of an inherent difference in the physics of coupled air–sea interactions and upper ocean variability. It is argued that in the presence of large coupled model errors and in the absence of coupled data assimilation, the competing and at times additive influence of the initialization and model errors can change the behavior of the air–sea interaction physics and upper ocean dynamics.

scholarly journals ENSO’s Impact on the Gap Wind Regions of the Eastern Tropical Pacific Ocean*

2012 ◽  
Vol 25 (10) ◽  
pp. 3549-3565 ◽  
Author(s):  
Michael A. Alexander ◽  
Hyodae Seo ◽  
Shang Ping Xie ◽  
James D. Scott
Keyword(s):  
Pacific Ocean ◽  
Boundary Conditions ◽  
El Niño ◽  
El Nino ◽  
Tropical Pacific ◽  
Surface Fluxes ◽  
Ocean Dynamics ◽  
Tropical Pacific Ocean ◽  
Variable Surface ◽  
Sst Anomalies

Abstract The recently released NCEP Climate Forecast System Reanalysis (CFSR) is used to examine the response to ENSO in the northeast tropical Pacific Ocean (NETP) during 1979–2009. The normally cool Pacific sea surface temperatures (SSTs) associated with wind jets through the gaps in the Central American mountains at Tehuantepec, Papagayo, and Panama are substantially warmer (colder) than the surrounding ocean during El Niño (La Niña) events. Ocean dynamics generate the ENSO-related SST anomalies in the gap wind regions as the surface fluxes damp the SSTs anomalies, while the Ekman heat transport is generally in quadrature with the anomalies. The ENSO-driven warming is associated with large-scale deepening of the thermocline; with the cold thermocline water at greater depths during El Niño in the NETP, it is less likely to be vertically mixed to the surface, particularly in the gap wind regions where the thermocline is normally very close to the surface. The thermocline deepening is enhanced to the south of the Costa Rica Dome in the Papagayo region, which contributes to the local ENSO-driven SST anomalies. The NETP thermocline changes are due to coastal Kelvin waves that initiate westward-propagating Rossby waves, and possibly ocean eddies, rather than by local Ekman pumping. These findings were confirmed with regional ocean model experiments: only integrations that included interannually varying ocean boundary conditions were able to simulate the thermocline deepening and localized warming in the NETP during El Niño events; the simulation with variable surface fluxes, but boundary conditions that repeated the seasonal cycle, did not.

Thorium-derived dust fluxes to the tropical Pacific Ocean, 58Ma

2012 ◽  
Vol 87 ◽  
pp. 194-209 ◽  
Author(s):  
Stella C. Woodard ◽  
Deborah J. Thomas ◽  
Franco Marcantonio
Keyword(s):  
Pacific Ocean ◽  
Tropical Pacific ◽  
Tropical Pacific Ocean ◽  
The Tropical Pacific

scholarly journals Eddy-mean flow decomposition and eddy-diffusivity estimates in the tropical Pacific Ocean: 1. Methodology

1998 ◽  
Vol 103 (C13) ◽  
pp. 30855-30871 ◽  
Author(s):  
Sonia Bauer ◽  
Mark S. Swenson ◽  
Annalisa Griffa ◽  
Arthur J. Mariano ◽  
Ken Owens
Keyword(s):  
Pacific Ocean ◽  
Eddy Diffusivity ◽  
Tropical Pacific ◽  
Tropical Pacific Ocean ◽  
Mean Flow ◽  
The Tropical Pacific ◽  
Flow Decomposition
Sign in / Sign up

Export Citation Format

Share Document