Variability of the North Atlantic Subtropical High in the Year’s Wet Season and Its Relationship with the Tropical Cyclonic Activity

Abstract

The variability of the North Atlantic Subtropical High and its influence on the behavior of tropical cyclogenesis are characterized and analyzed. The database of the Center for Environmental Prediction and the Center for Atmospheric Research was consulted for the months of May to October between 1950 and 2019. The variables used were the central pressure to determine the position of the North Atlantic Subtropical High on the surface and the geopotential to obtain the position of the anticyclonic center at 850 hPa, as well as the geopotential at 500 and 200 hPa over the region of the anticyclone on the surface. This system weakens at the surface level and intensifies at other tropospheric levels. The relationship with tropical cyclone activity in the Atlantic basin was assured and updated. Low levels play an important role in tropical cyclogenesis; the position and extension of the anticyclonic ridge at this level are the parameters with the highest coincidence, and in the present century, the anticyclone parameters in the months of June and July have increased their significance.

Keywords

• North Atlantic Subtropical High
• tropical cyclone activity
• seasonal forecast
• climate variability