| Summary: | Tropical cyclones (TCs) are responsible for the destruction of millions of dollars in property and potentially the loss of hundreds of lives each year. Although essentially a stochastic meteorological phenomena, they owe their genesis, existence and fate to many natural modes of climate variability. As such, TCs are often subject to the larger phenomena governing them or in proximity, including but not limited to sea surface temperatures (SSTs), large-scale atmospheric circulation patterns, wind shear, and the detailed meteorological situation in the basin in which they develop. Thus, despite the independent nature of hurricanes and their course through any given basin, a large degree of their genesis and propagation results from several key factors, which allows for ease in forecasting of intensity and movement. One such factor as sea level pressure (SLP) teleconnections govern mesoscale to hemispheric weather and climate patterns, and have been shown to correlate with temperature and precipitation patterns across the globe. They are often seen responsible for fluctuations in storm patterns and movement, as is the case with the North Atlantic Oscillation (NAO). NAO, which measures the intensity between the Bermuda or Azores high and the Icelandic low, is thought to shift climate in the North Atlantic (Gray 1984). The positive phase includes a stormy Sargasso Sea (western Atlantic between Bermuda and the East Coast) with a wet East Coast and Europe when both pressure regimes are strong. The negative phase includes a southerly shifted storm flow and contrary climate when both pressure regimes are weak. Investigations into the phase relation between NAO and North Atlantic (NA) TCs have shown little or no correlation, but these studies lack detailed examination. This study aims to analyze the temporal and spatial patterns between thepositive, negative and neutral phases of NAO and NATC frequency and intensity over monthly, multi-monthly, and seasonal time intervals. NAO indices were analyzed and divided by year for ...
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