Lobster settlement data from eleven regions across New England were compared to monthly geopotential height, wind field, and temperature data extracted from NCEP North American Regional Reanalysis dataset. Geopotential heights in September were the best indicator of lobster settlement. The strongest correlations were found in northern Massachusetts (r=0.92, p<0.001) and in New Brunswick (r=0.71, p=.005). The correlation between settlement and geopotential height was weaker between these sights, but still significant (r=0.58, p=0.019). Settlement in Rhode Island occurs earlier in the summer, and the best correlation with geopotential heights was from July (r=0.62, p=0.014). Years of high settlement are characterized by onshore winds or onshore Ekman transport. Northerly winds over New England, rotating cyclonically to southwest winds over the Atlantic, prevail for years with poor settlement.
The specific driver connecting geopotential height to lobster settlement is still not clear. Geopotential height fields will affect surface winds, forcing ocean surface currents and Ekman transport. Clear skies associated with high pressure would enhance the sea breeze, possibly further driving lobster larvae to the shore.
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