GOÑI, Gustavo J., Dr.

Gustavo Jorge Goni

Gustavo.Goni “at” noaa.gov

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My publications provide a good reference to my research work.

Analysis of some of the satellite-derived products provides the motivation for my research.

Tropical Cyclone Heat Potential (link)

The intensification of tropical cyclones involves a combination of different favorable atmospheric conditions such as atmospheric trough interactions and vertical shear, which lead to good outflow conditions aloft. As a result of this, inflow conditions in the near-surface layer are enhanced. Clearly, as this process continues over the scale of the storm, the upper ocean provides the heat to the atmospheric boundary layer and the deepening process. In this scenario, the upper ocean thermal structure has been thought to be a parameter that only played a marginal role in tropical cyclone intensification. However, after a series of events where the sudden intensification of tropical cyclones occurred when their path passed over oceanic warm features, it is now being speculated that it could be otherwise. While the investigation of the role of these rings and eddies is a topic of research in a very early stage, preliminary results have shown their importance in the intensification of hurricane Opal (Shay et al, 2000). Therefore, the monitoring of the upper ocean thermal structure has become a key element in the study of hurricane-ocean interaction with respect to the prediction of sudden tropical cyclone intensification. These warm features, mainly anticyclonic rings and eddies shed by the Loop Current, are characterized by a deepening of several tens of meters of the isotherms towards their centers and with different temperature and salinity structure than the surrounding waters.

Time Series of surface currents (link)

North Brazil Current and rings (link)

The North Brazil Current (NBC) is a western boundary current that flows off the coast of northeast Brazil and retroflects between 4°N and 10°N. The NBC sheds large anticyclonic rings that move northwestward along the continental break. (Didden and Schott, 1993). These warm rings could play an important role in the net meridional transport of warm water in the upper layers of the Atlantic Ocean as part of the meridional overturning circulation (MOC).

Agulhas Retroflection (link)

The transfer of warm water from the Indian Ocean to the South Atlantic subtropical gyre takes place mostly in the form of rings and filaments formed when the Agulhas Current retroflects south of Africa between 15°E and 25°E. It has been observed a closed correlation between the transport of this current and the shedding of rings (Goni et al, JMR, vol.55, 861-883, 1997). Monitoring both the Agulhas transport into the South Atlantic in the upper kilometer of the ocean and the number of rings shed at its retroflection provides a means of detecting any substantial changes in the inter-ocean water exchange.

Brazil-Malvinas Confluence (link)

The subtropical gyre in the South Atlantic is the dominant and permanent large-scale feature characterized by its anticyclonic circulation. The upper ocean circulation in this region is characterized by a complex number of flows at different spatial scales [Peterson and Stramma, 1991]. The southern branch of the South Equatorial Current, the northern limb of the gyre, bifurcates off Brazil at approximately 15°S with its southern branch forming the Brazil Current, a western boundary current that is the southwestern branch of the gyre. The eastward flowing South Atlantic and the northward flowing Benguela currents complete the main circulation feature in the gyre.