New England Hurricane Climatology
By Paul Homewood
I mentioned Prof Scott Mandia’s take on the Long Island Express hurricane of 1938. Scott, who is a fully paid up member of the hockey team, also has this climatology of North East hurricanes:
New Yorkers give little thought to hurricanes since Long Island is so far from the warm, tropical oceans that feed hurricanes. However, according to the 1984 Hurricane Damage Mitigation Plan by the Long Island Regional Planning Board, several hurricanes and 15 tropical storms have made landfall in this area since 1886. According to historical record, there have been five "epic hurricanes" (Category 3 or higher on the Saffir Simpson Scale) in the years 1938, 1893, 1821, 1815, and 1635 (Hughes).
An empirical study of 20 past hurricanes that have impacted the New York City and Long Island coast regions by Scheffner and Butler (1996) found that the return period of a category 3 or greater hurricane is approximately 80 years. A strong category 3 or minimal category 4 hurricane has a return frequency of approximately 200 years. Therefore, it is not unlikely that another "epic" hurricane will strike the Long Island coastal region in the coming decades.
Research done by hurricane experts at the National Center for Atmospheric Research (NCAR) reveals that hurricane frequency in the Atlantic Ocean and Caribbean Sea regions runs on a 20-30 year cycle. (Time, 1998) The graphic to the left (Risk Prediction Initiative, 1998) clearly illustrates this cycle. The last intense period was in the 1950’s and 1960’s with a lag between 1970 and 1994. The hurricane frequency is on the upswing once again which increases the chances for landfall everywhere along the east coast of the U.S.
Unfortunately, in the past few decades, the coastal population has also increased substantially which further increases the hurricane risk. Even though more sophisticated forecasting tools such as satellites and Doppler radar are providing more lead-time for issuing warnings, the threat of massive deaths remains fairly high due to the increased coastal populations.
Source: USGS, 1998
Source: Time Magazine, 1998
The tables to the right show probability estimates for the occurrence of various disaster events (including hurricanes) that could impact the U.S. in the future. While it may not be surprising to see that there is a >99% likelihood of at least 10 deaths from a hurricane in the next 10 years, it should be noted that the data indicates a 71% probability of 1,000 deaths from a hurricane in the next 20 years!
Take good note of his first graph, showing a much reduced number of hurricanes in the 1970’s and 80’s. The 20-30 year cycle he refers to is the AMO.
Remember this fact when people claim that hurricanes have increased since we started satellite monitoring in the 1970’s.
In the meantime, we can be grateful that the North East has not since had to experience any hurricane anywhere as near as powerful as the Long Island Express, or indeed the other four “epic” hurricanes in earlier centuries. Indeed, the last hurricane to actually make landfall in New England was Bob in 1991, which came ashore as a Cat 2.