20th Century variability of the Gulf of California SST

Annually averaged sea surface temperature anomalies at four 2°x2° quadrants at the Gulf of California, Mexico) were constructed using ICOADS (International Comprehensive Ocean-Atmosphere Data Set) and ERSST (NOAA Extended Reconstructed SST data set), contrasted to similar latitudinal quadrants at the Pacific coast of the Baja California peninsula to assess their independent variation, given the way ERSST data are constructed by geographical interpolation and their close vicinity to the Pacific coast. Later they were compared to large scale environmental indices (Pacific Decadal Oscillation index, PDO; and Nino 3 index, N3) to examine their relationships. Hamming filters were utilized to isolate high ( 20 years) frequencies for comparison. The relationships of the decadal scale variation and the relative abundance of stocks being harvested by two outstanding fisheries (penaeid shrimps and California sardine) are explored given their strong response to environmental variations because of their short life cycle and fast growth.