Satellite SST images of the Loop Current in the Gulf of Mexico

March 13th, 2010 |
MODIS Sea Surface Temperature product

MODIS Sea Surface Temperature product

AWIPS images of the 1-km resolution MODIS Sea Surface Temperature (SST) product (above) showed some intricate details in the SST structure of the warm Loop Current in the eastern Gulf of Mexico on 13 March 2010. Note the “swirl” of slightly cooler SST values (lighter orange colors) in the northern portion of the Loop Current.

A comparison of the MODIS SST product with the RTG_SST High Resolution model analysis (below) serves to illustrate how satellite data can add value in situations where even high-resolution models struggle to accurately depict some of the smaller-scale SST structures that were present in the Gulf of Mexico. For example, the RTG_SST_HR analysis placed the axis of warmest SST values over the eastern portion of the Loop Current, where MODIS SST values were in fact a few degrees F cooler than they were over the warmer western portion. The highest MODIS SST values in the western part of the Loop Current were around 80º F (darker red colors), which were about 4-5º F higher than what was indicated in that area by the RTG_SST_HR analysis.

MODIS SST product + RTG_SST Hi-Res SST model surface temperature

MODIS SST product + RTG_SST Hi-Res SST model surface temperature

Three days earlier, AVHRR SST values in the southern portion of the Loop Current were as warm as 83º F (below) — however, brisk surface winds associated with the passage of a strong cold front helped to lower the SST values a bit, due to mixing and upwelling of slightly cooler water from below the surface.

AVHRR Sea Surface Temperature product

AVHRR Sea Surface Temperature product

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