Revisiting the cold season surge generating storms of the east coast in the 20th century

Tuesday, 16 December 2014
Dong Eun Lee, Columbia University of New York, Palisades, NY, United States, Yochanan Kushnir, Columbia Univ, Palisades, NY, United States and James F Booth, CUNY City College, New York, NY, United States
Cold season storms in the East coast of the United States often threaten the coastal livelihood. This is a study to connect the recorded extreme cold season surges with the storms in the past, spanning from the early 20th Century.

We find the 20th century reanalysis data (20CR) useful for this study, for its temporal coverage sufficiently overlaps with the modern tidal records. The storm tracks are obtained from the cold season (NDJFMA) sea level pressure field from 20CR, using the popular tracking algorithm by K.Hodges. In seeking for fidelity in the storm data, we made two major efforts: The climatology and the known climate signals imbedded in the track data are verified against those of ERA-interim reanalysis, and against the storms tracked by an independent algorithm (GISS-MCMS). In addition, it is statistically confirmed that the storm tracks and the sea level pressure fields based on 20CR around the east coast area exhibit temporal homogeneity.

In the Battery, we select top 100 cold season water displacement events from the 6-hour mean water height data from 1927 to 2012, with linear trend and tide removed. Among the tracks passing close enough to the Battery, we found 91 matches. Distinctive track characteristics stand out when the positive surge events are separated from the negative surge events. More characteristic parameters of the storms are investigated according to further surge classification.