The Effects of Low-Frequency Climate Oscillations on Interannual Variations in East Coast Winter Storm Tracks

• Main Author: Saslo, Seth
• Format: Thesis
• Language: English
• Published: 2012
• Subjects: Arctic; Pacific; North Atlantic; North Atlantic oscillation
• Online Access: https://hdl.handle.net/1813/29091

Correlations between low-frequency climate oscillations and East Coast Winter Storm location are explored using the Hirsch et al. (2001) definition of ECWS and NCEP Reanalysis data. Relevant climatic factors are identified, and comparisons are drawn in ECWS geographic frequency between significant positive and negative phases of these climate oscillations through an automated procedure. It is found that the Multivariate ENSO Index, the North Atlantic Oscillation, the Arctic Oscillation, and the Pacific Decadal Oscillation are significantly correlated to ECWS frequency at specified grid points along the East Coast. Furthermore, it is apparent that select modes of these climate oscillations have a more profound effect on ECWS frequency than others: A positive ENSO keeps storms on a more southerly route; A negative NAO and AO confine storms to the mid- and north coast; and a negative PDO moves storms to the north. Maps of average 500 mb heights during these storm days are created and sorted by sign and magnitude of climate index, and aid to an explanation of storm motion through temperature and height gradients as well as trough axis position.