Some aspects of the oceanography of the Gulf of Mexico using satellite and in situ data

Abstract

Satellite infrared data and in situ data were combined to study synoptic-scale and mesoscale fronts in the Gulf of Mexico in the period 1973-1977. Deep northward penetrations of the Loop Current were noted in the winter, and a major warm gyre developed in the winter, 1974. Other major warm gyres were seen to develop in the early spring (1974 and 1977). In all cases, a very large meander developed off the southern part of the west Florida shelf prior to the development of the major warm gyre. Smaller meanders were seen to move along the Loop Current boundary at an average speed of 28 kin/day and with an average wavelength of 210 kin. I present affiliation: theAtlantic Oceanographic and Meteorological Laboratory, Miami, Florida 33149. Paper number 9C 1319. 0148-0227/79/009C-1319501.00 coordinates), and the feature was transferred to a scaled map of the region of interest. Because there were a considerable number of landmarks in the Gulf of Mexico, it is estimated that there was, at most, a 10%-km error in gridding the satellite images and transferring features to scale maps. The analyses of the scale maps are used to develop statistics on the perturbation of interest (e.g., lifetime, speed, stationarity, maximum and minimum dimensions, etc.).In some months, particularly June-September (but in some cases May and October also), the thermal contrast at the surface was not sufficient to detect oceanic features using satellite infrared radiometry. This does not mean that features, such as the Loop Current or boundary eddies, did not exist, but simply means that there was no thermal manifestation of the feature at the surface. For example, it has been shown that a well-developed Loop Current exists in the Gulf of Mexico in the summer. Meanders and eddies associated with the Loop Current would also exist at that time of year; the fact that statistics on such features were determined for the fall, winter, and spring should not be interpreted to mean that such features did not exist in the summer or are necessarily more common in the fall, winter, and spring.The infrared imagery yields the relative variation of sea surface temperature and was used to define ocean surface thermal boundaries (fronts) quite well. In order to obtain absolute values of temperature from the IR data, ground truth calibrations were required. The ground truth calibrations were determined from in situ surface and subsurface temperature data, for the period 1973-1977, obtained from the National Oceanographic Data Center (NODC) and the National Climatic Center (NCC). The in situ data were used to determine specific magriit.udes of sea surface temperature for perturbations of interest. In order to accomplish this, areas on the cold and warm side of specific thermal perturbations were defined by noting latitude and longitude boundaries of each area. The latitude and longitude boundaries, together with information on the period (day, month, and year), were used as input parameters for an algorithm that searched the in situ data files to determine whether ...

The Interaction between Hurricane Opal (1995) and a Warm Core Ring in the Gulf of Mexico

“…This cold water represents the filamentation process where streamers of colder west Florida shelf water are entrained into the loop current and WCR, which has been realistically reproduced by MOM2. The physical effect compares well with the analysis of Vukovich and Maul (1985).…”

“…2). This situation was due to strong solar heating that occurs during the summer months, particularly June-September (Shay et al 1992;Vukovich et al 1979). The strong solar heating creates a thin layer of warm water, thereby masking the underlying features.…”

A comparison of sampling methods for larvae of medium and large epipelagic fish species during spring SEAMAP ichthyoplankton surveys in the Gulf of Mexico

“…Major circulation patterns in the deep Gulf, off continental shelves, are defined by dynamics of the Loop Current and anticyclonic and cyclonic eddies (Vukovich et al 1979;Vukovich and Crissman 1986;Biggs 1992;Castellanos and Gasca 1999), and by wind-driven and convective mixing (Muller-Karger et al 1991;Melo Gonzalez et al 2000). Previous studies have associated increased larval pelagic abundance with some of these specific mesoscale features (Richardson et al 2009;Muhling et al 2010;Rooker et al 2012;Lindo-Atichati et al 2012).…”

Gymnodinium breve red tide blooms: Initiation, transport, and consequences of surface circulation

“…1). The extent of northward penetration of the Loop Current (Maul 1977;Vukovich et al 1979), its spinoff eddies (Dietrich and Lin 1994;Sturges 1994), and its intrusions onto the west Florida continental shelf vary seasonally (Huh et al 198 1) and greatly affect the potential of bloom initiation, transport, and retention (Haddad and Carder 1979;Haddad 1982;Lee et al 1994). Rotating eddies can be shed from the Loop Current and propagate westward across the gulf (Liepper et al 1972;Maul and Vukovich 1993).…”