Spatial and temporal variability of sea surface temperature and fisheries distribution with the North Atlantic Oscillation

Abstract

Increasing evidence supports relationships between fisheries distribution and climate variability. The main driver of climate variability in the North Atlantic Ocean is the North Atlantic Oscillation (NAO). Fisheries distribution is influenced by sea surface temperature (SST), which displays a dynamic relationship with the NAO. To assess these relationships, we conducted a spatial and temporal analysis of SST, fisheries distribution, and the NAO from 1986 to 2008 in the Northwest Atlantic and Gulf of Mexico. We conducted a pixel-level linear regression analysis with the USGS Curve Fit tool in ArcMap to examine the spatial patterns of correlation coefficients and goodness of fit between monthly SST and monthly NAO index. We identified five regions in the Northwest Atlantic, and two regions in the Gulf of Mexico, where coefficients demonstrated relatively significant correlation between SST and the NAO. These regions were consistent with local ocean circulation patterns. To assess the relationship between the NAO and fisheries distribution in the identified correlation regions, we calculated linear regressions between tuna and swordfish catches and effort distribution with the NAO as the explanatory variable. Our results suggest that our linear model with the NAO as the single explanatory variable was too simplistic to explain fisheries catch and distribution variability. Further study using different models and explanatory variables may elucidate significant relationships between SST, fisheries distribution, and the NAO. Trends between fisheries and the NAO may provide insight into future effects of climate change on fish stocks with implications for fisheries management.