A cyclonic gyre within the eastern tropical South Atlantic is resolved by an extensive oceanographic station array obtained in 1983 and 19&4. The gyre is centered near nos and SOE with a sea surface relief relative to 1500 decibars (db) of8 dyn em. The 500 db surface relative to 1500 db reveals a much diminished cyclonic circulation, shifted slightly to the south. The weak baroclinic expression...

An earlier study showed that an atmosphere–ocean model of the Pacific develops a midlatitude oscillation that produces decadal sea surface temperature (SST) variability on the equator. The authors use the ocean component of this model to understand better how subtropical wind stress oscillations can cause such SST variability. The model ocean consists of three active layers that correspond to t...

0079-6611/$ see front matter Crown Copyright 2 doi:10.1016/j.pocean.2008.07.002 * Corresponding author. Tel.: +61 2 9385 7071; fax E-mail address: [email protected] (W.P. Sijp). We examine the effect of a northward shift in the position of the southern hemisphere subpolar westerly winds (SWWs) on the vertical and horizontal distribution of temperature and salinity in the world ocean. A northwa...

During the 1950s and 1960s, an extensive field study and interpretive effort was made by researchers, primarily at the Scripps Institution of Oceanography, to sample and understand the physical oceanography of the eastern tropical Pacific. That work was inspired by the valuable fisheries of the region, the recent discovery of the equatorial undercurrent, and the growing realization of the impor...

The maintenance of the ocean general circulation requires energy input from the wind. Previous studies estimate that the mean rate of wind work (or wind power) acting on the surface currents over the global ocean amounts to 1.1 TW (1 TW ! 10 Watts), though values remain highly uncertain. By analyzing the output from a range of ocean-only models and data assimilations, we show that the tropical ...

Two state-of-the-art Earth systemmodels (ESMs) were used in an idealized experiment to explore the role of mountains in shaping Earth’s climate system. Similar to previous studies, removing mountains from both ESMs results in the winds becoming more zonal and weaker Indian and Asian monsoon circulations. However, there are also broad changes to the Walker circulation and El Niño–Southern Oscill...

The greater Agulhas Current region is an important component of the climate system, yet its influence on carbon and nutrient cycling poorly understood. Here, we use nitrate isotopes (δ15N, δ18O, Δ(15–18) = δ15N–δ18O) to trace regional water mass circulation investigate nitrogen in adjacent recirculating waters. deep intermediate waters record processes occurring remotely, including partial assi...

Satellite and in situ observations in the equatorial Atlantic Ocean during 2002–03 show dominant spectral peaks at 40–60 days and secondary peaks at 10–40 days in sea level and thermocline within the intraseasonal period band (10–80 days). A detailed investigation of the dynamics of the intraseasonal variations is carried out using an ocean general circulation model, namely, the Hybrid Coordina...

During the warm early Pliocene (approximately 4.5 to 3.0 million years ago), the most recent interval with a climate warmer than today, the eastern Pacific thermocline was deep and the average west-to-east sea surface temperature difference across the equatorial Pacific was only 1.5 +/- 0.9 degrees C, much like it is during a modern El Niño event. Thus, the modern strong sea surface temperature...

The breeding method has been implemented in the NASA Seasonal-to-Interannual Prediction Project (NSIPP) coupled general circulation model (CGCM) with the ultimate goal of improving operational seasonal to interannual climate predictions through ensemble forecasting and data assimilation. This is the first attempt to isolate the evolving ENSO instability and its corresponding global atmospheric ...