Abstract
The distribution of particulate matter (PM) and particulate organic carbon (POC) was determined during the Northeast Gulf of Mexico Chemical Oceanography and Hydro-graphy program (NEGOM). The hydrography and physical forcing functions were examined to explain particulate matter distribution. PM and POC were determined for discrete samples, and PM was also compared with in situ beam attenuation measure-ments in order to make estimations of continuous particle concentration profiles. Measurements were made three times per year for three years, during 1997-1998, 1998-1999, and 1999-2000, but only the first two years' worth of results are reported here. PM distributions vary seasonally and interannually. General patterns tend to be fairly consistent spatially and temporally during fall and spring, but intensity changes accord-ing to season. Differences present at the surface appear to be due mainly to riverine input of nutrients and particles from the several major rivers that flow into the northeastern Gulf of Mexico. Wind-forced circulation appears to be a minor influence on surface particulate distribution. Secondary eddies can have an effect upon distribution, as seen with an anticyclonic feature over the upper slope during Summer 1998 which entrained less saline, high particulate river water offshore. A similar effect was noted during Summer 1999, but to a lesser degree. A shelf edge current associated with anticyclonic flow seems to be a mechanism responsible for the appearance of nepheloid layers on the outer shelf.
Bernal, Christina Estefana (2001). Spatial and temporal distributions of particulate matter and particulate organic carbon, Northeast Gulf of Mexico. Master's thesis, Texas A&M University. Available electronically from
https : / /hdl .handle .net /1969 .1 /ETD -TAMU -2001 -THESIS -B47.