Investigating Annual Relationships between Climate Indices and Tropical Cyclone ACE Values for the North Indian, North Pacific, and North Atlantic Oceans

• Other Authors: Sala, Christopher Michael (authoraut)
• Format: Bachelor Thesis
• Language: English
• Subjects: Indian; Pacific; Soi; North Atlantic
• Online Access: http://purl.flvc.org/fsu/fd/FSU_libsubv1_scholarship_submission_1617980978_c7b921fd; http://fsu.digital.flvc.org/islandora/object/fsu%3A763300/datastream/TN/view/Investigating%20Annual%20Relationships%20between%20Climate%20Indices%20and%20Tropical%20Cyclone%20ACE%20Values%20for%20the%20North%20Indian,%20North%20Pacific,%20and%20North%20Atlantic%20Oceans.jpg

This study examined statistical relationships in seasonal tropical cyclone activity among Northern Hemisphere ocean basins, in particular the North Indian Ocean. Activity in each basin is measured by the seasonal accumulated cyclone energy (ACE), defined as the sum of the squares of the maximum sustained surface wind speed in knots measured every six hours for all named storms while they are at least tropical storm intensity (≥ 34 kt). Specifically, we used annual ACE time series for 1982–2016 (35 years) for the North Indian, North Pacific (and subdivided into eastern and western), and North Atlantic Oceans. We augmented the ACE values with 15 teleconnection indices for 1989–2011 (23 years) from various sources. Although ACE is anticorrelated between the North Pacific and the North Atlantic, annual ACE values for the North Indian Ocean show negligible simultaneous correlation with ACE values for either the North Pacific or North Atlantic Oceans. However, North Indian Ocean ACE is lag correlated with Pacific activity. North Indian Ocean ACE has correlations of 0.44, 0.33, and 0.21 with the eastern North Pacific Ocean ACE for 1, 2, and 3 years earlier. Therefore, ACE for the Northeast Pacific has a modest predictive value for North Indian Ocean ACE. The two largest simultaneous correlations with North Indian Ocean ACE were with West Pacific (WP) teleconnection pattern and the May-November values of the first primary component of the velocity potential Madden-Julian Oscillation (VPM1). The North Pacific Ocean ACE was the ENSO Index (MEI.v2) for the annual and June-November time scales. The North Atlantic Ocean’s largest simultaneous correlations were the VPM1 for the annual time scale and Southern Oscillation Index (SOI) for the June-November time scale. Meteorology, Indian Ocean, Atlantic Ocean, Pacific Ocean, West Pacific teleconnection pattern, ACE, hurricane, tropical cyclone