A Comparison of the Impacts of Hurricane Irene and the “Friday the 13 th” Northeaster in New Jersey.
Omar L. Lopez, Jennifer Wehof and Jon K. Miller: Center for Maritime Systems, Stevens Institute of Technology,
Castle Point on Hudson, Hoboken, NJ 07030. (201) 216-5300
E-mails: olopez@stevens.edu, jwehof@stevens.edu, jmiller@stevens.edu
Hurricane Irene hit the coast of New Jersey in August 2011 and was touted as the most
significant storm to impact the region in the past 150 years. Almost two years before, in November
2009, a strong Northeaster struck the New Jersey coast and has been called the Friday the 13 th
Northeaster. Both storms resulted in a Presidential Disaster Declaration and millions of dollars in
coastal damage. Post-storm surveys conducted by the New Jersey Department of Environmental
Protection concluded that overall, the coastal erosional damage from Hurricane Irene was less
significant than that which occurred during the Friday the 13 th Northeaster. Comparing wave data for
the two storms, the Friday the 13th Northeaster exceeded the 25-year return period, while Hurricane
Irene had significant wave heights closer to a 5-year storm. Figure 1 gives a detailed look at the
interaction between the water level, wave height, and storm duration. The Friday the 13th Storm
sustained wave heights over 15 feet for four tidal cycles. Hurricane Irene had a short duration surge
accompanied with waves over 15 feet for only one tidal cycle. To compare the erosional qualities of
the two storms, several storm indices were applied. The Dolan-Davis scale and Kriebel Intensity Index
were developed for Northeasters only and categorize storms into 5 classes based on their significant
wave height and storm duration. The Kriebel Intensity Index for the Friday the 13th Storm was found to
be a class 2 storm. However, the same storm using the Dolan-Davis scale was calculated as a class 5
storm. The Miller-Livermont Storm Erosion Index (SEI) is the only applicable index found to be
accurate for both hurricanes and northeasters. This index suggests that while both storms were similar
in intensity during the height of the storm, the duration of the Friday the 13th Storm was what allowed
it to do more damage to the beach. Storm erosion simulations conducted with the storm-induced
erosion model SBEACH generally confirm this observation. The purpose of this research was to
compare the difference in coastal erosion between a hurricane and a Northeaster using the data
available from two recent major events.
Figure 1: Wave height (NOAA Buoy 44009) and water level (Atlantic City) during Northeaster (left) and Hurricane Irene (right).
References:
Dolan, R., and R.E. Davis., 1992. An Intensity Scale for Atlantic Coast Northeast Storms, Journal of Coastal Research, 8, 352-364.
Kriebel, D.L., R. Dalrymple, A. Pratt, and V. Sakovich. 1996. Shoreline Risk Index for Northeasters, Proceedings of the International Conference and
Exposition on Natural Disaster Reduction, ASCE, 251-252.
Miller, J.K., and E. Livermont. 2008. A Predictive Index for Wave and Storm Surge Induced Erosion. Proc. 31st Coastal Eng. Conf., World Scientific Press,
561-572.