Abstract
Warm Core Rings (WCRs) in the Gulf Stream (GS) region have a significant impact on the distribution of temperature and salinity in the slope and shelf seas. This study examines the seasonal and inter-annual variability of WCRs shed from the GS using oceanographic charts from 2000 to 2016. A WCR census was first developed for these 17 years to document their dates of birth and death, locations at birth and death, and their sizes at birth and near death. The seasonal pattern shows more frequent WCR formation during the months of May, June, and July in the slope sea. The spatial distribution of WCR formation showed that about two-thirds of the rings were formed between 65°W and 55°W suggesting increased amplitude of meandering here. Regionally, most ring births occurred evenly between 65°W and 60°W and 60°W and 55°W, and decreased westward. The WCR formation events between 75°W and 65°W show significant correlation (r = -0.627, P-value = 0.007) with the Gulf Stream Index (GSI, Taylor and Stephens, 1998). The WCR births do not show any significant correlation with the state of the North Atlantic Oscillation (NAO) from 2000 to 2016, in contrast to the findings of the Chaudhuri et al. (2009) study which showed a positive correlation of 0.51 between NAO and WCR. Finally, an experimental probability index has been developed for predicting the lifespan and size of a WCR at birth, given the region and the month of birth.