Variability in the Occurrence of Tropical and Extratropical Cyclones in the Atlantic Ocean and Its Climatic and Hydrological Determinants

The main objective of this study was to investigate the variability in annual counts and northern extent cyclones North Atlantic years 1970–2019. Cyclones were divided into tropical (TCs), called hurricanes Atlantic, extratropical (ETCs), transformed from TCs. Linear regression methods Pearson’s correlation coefficient applied. trend numbers is upward for both types cyclones. maximum TCs shows a decreasing trend, while that ETCs clearly increasing. Hurricane show moderate positive (correlation 0.31) with Southern Oscillation Index (SOI) negative (−0.34) (NAO) index. For SOI months second half year, there strong (up 0.51) number September–October. highest (0.65) observed between Multi-decadal (AMO). have been shown correlate positively water temperature western Pacific, negatively eastern Pacific Ocean. A significant relationship has also recorded SST north east 0.4 0.6).