Using NASA remote sensing data for coastal monitoring in the northern Gulf of Mexico: a case study

The coastal region comprising the states of Louisiana, Mississippi, and Texas is frequently impacted by meteorological events such as frontal passages and hurricanes. The region is also influenced by the Mississippi river, which is seventh largest in terms of water and sediment discharge among the major rivers of the world that strongly influences the physical and biogeochemical properties in the northern Gulf of Mexico. NASA remote sensing data such as winds from QuikSCAT, sea surface height anomaly (SSHA) from Jason-1, ocean color and sea surface temperature (SST) from MODIS satellite sensors were assessed during the period that Hurricane Rita made landfall on 24 September 2005 along the Louisiana-Texas border in the western Gulf of Mexico. QuikSCAT winds revealed the northwestward movement of the hurricane and gradients in the distribution of wind speed around the hurricane center. Altimeter data indicated changes in pattern of the SSH anomaly field and a displacement of the warm and cold core eddies following the hurricane. Although limited by cloud cover, the MODIS 8-day average chlorophyll imagery obtained before and after the hurricane indicated an offshore displacement of higher chlorophyll concentrations while the MODIS 250 m resolution true color imagery showed high levels of suspended particulate matter in the impacted coastal region. MODIS SST indicated a cooling of the surface waters around and east of the track following Hurricane Rita. The use of multiple remote sensing products provided better insights of the oceanographic response to Hurricane Rita.