Sea surface temperature
Ocean temperatures can have both direct and indirect effects on a wide range of ecosystem components. Temperature has already appeared to be a factor in preference-driven shifts in fish distributions in the Gulf of Mexico over recent decades (Pinsky et al. 2013, Fodrie et al. 2010). Species that are immobile such as corals may be subject to mortality when exposed to changes in temperature; indeed, Gulf corals have experienced bleaching and death in recent years in response to rising ocean temperatures (Coles and Riegl 2012). Temperature shifts may also have indirect effects on human communities; for example, by inducing disease outbreaks in commercially important shellfish species (Harvell et al. 1999).
Here we report average monthly SST indices, calculated for select regions within the GoM, using the one-quarter degree Daily High-Resolution Blended SST Analysis product (AVHRR product). A principal components analysis was used to analyze spatial patterns in SST variability across time, and formed the basis of defining subregions. In all three regions, temperatures have increased gradually over three decades, although the West has warmed more rapidly than the East. The Texas subregion has increased at a linear rate of 0.31 degrees Celsius per decade, whereas the rate of increase has been slightly lower for the Louisiana shelf and West Florida shelf subregions (0.22 and 0.20 degrees Celsius per decade, respectively).