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Northeastern U.S. Hurricanes and Hurricane Risk – a discussion following Hurricane Sandy (L. Braile, Nov. 11, 2012)
Hurricane Sandy began as a tropical depression south of Jamaica on October 22, 2012, becoming a tropical storm later that day. “Sandy moved
slowly northward toward the Greater Antilles and gradually intensified. On October 24, Sandy became a hurricane, made landfall near Kingston,
Jamaica, a few hours later, re-emerged into the Caribbean Sea and strengthened into a Category 2 hurricane. On October 25, Sandy hit Cuba, then
weakened to a Category 1 hurricane. Early on October 26, Sandy moved through the Bahamas. On October 27, Sandy briefly weakened to a tropical
storm and then re-strengthened to a Category 1 hurricane. Early on October 29, Sandy curved north-northwest and then moved ashore near Atlantic
City, New Jersey as a "post-tropical cyclone" (http://en.wikipedia.org/wiki/Effects_of_Hurricane_Sandy_in_the_United_States).
In the NE United States, hurricane Sandy combined with an upper level low pressure system and became a very large storm that impacted one of the
most densely populated areas of the country. Upon landfall, winds were up to 90 mph but weaken considerably with time. Because the highest
winds and greatest storm surge are usually in the NE quadrant of the storm, the hardest hit areas were north of Atlantic City, New Jersey, hitting the
northern coastal region of New Jersey and SE New York. Rainfall was intense over a wide area (Figure 18) and enhanced flooding in coastal areas
caused by the storm surge (Figure 19). Flooding and trees blown down caused significant electric power and other infrastructure interruptions that
lasted over 10 days in many areas. Millions of people were affected and tens of thousands of homes were damaged or destroyed. At least 127 people
in the U.S. died in the storm and the damage total is estimated at $50 billion.
Although Sandy was not a major hurricane, it hit a very populated area and a coastal region (coastline, bays, river estuaries and barrier islands) that
has not seen a major hurricane since 1954 (see Tables 1 and 2). Since the 1950’s population growth and increased building (largely single family
dwellings) on barrier islands and along the coast at near sea level elevations increased the hazard of hurricane in the northeastern United States. The
maps, photographs and images shown below suggest the possibility that too much building has been allowed in hazardous coastal areas. The lack of
a major NE U.S. hurricane since 1954 has caused us to minimize or ignore the hazard. However, hurricanes have hit this area in the past, so it was
just a matter of time until it would happen again. And, Sandy could have been worse if it had greater intensity when it made landfall (it was a
category 1 hurricane and category 3 hurricanes have hit the area in the past.
Additional information and opinions of effects of hurricane Sandy are contained in the USA Today editorials:
http://web.ics.purdue.edu/~braile/EAS100online/Sandy.Beach.Homes.pdf
http://web.ics.purdue.edu/~braile/EAS100online/Sandy.Power.Grid.pdf
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Figure 1. Major U.S. landfalling hurricanes, 1899-1996 (http://www.ncdc.noaa.gov/oa/climate/severeweather/hurricanes.html).
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Figure 2. U.S. landfalling hurricanes, 1950-2011 Land-falling Hurricanes (http://www1.ncdc.noaa.gov/pub/data/images/2011-Landfalling-
Hurricanes-11x17.pdf).
4
Table 1. 20th
Century Storms making land-fall in New England (http://en.wikipedia.org/wiki/List_of_New_England_hurricanes)
Storm
Category
Season Date of landfall Peak intensity Intensity at landfall
New England Hurricane of 1938 Category 5 Category 3 1938 September 21, 1938
1944 Great Atlantic Hurricane Category 4 Category 1 1944 September 15, 1944
Hurricane Able Category 2 Tropical Depression 1952 September 1, 1952
Hurricane Carol Category 3 Category 3 1954 August 31, 1954
Hurricane Edna Category 3 Category 1 1954 September 11, 1954
Hurricane Diane Category 3 Tropical Storm 1955 August 18–19, 1955
Hurricane Cindy Category 1 Tropical Storm 1959 July 11, 1959
Hurricane Donna Category 5 Category 2 1960 September 12, 1960
Hurricane Esther Category 4 Tropical Storm 1961 September 26, 1961
Hurricane Alma Category 3 Extr. Storm 1966 June 13, 1966
Tropical Storm Doria Tropical Storm Tropical storm 1971 August 29, 1971
Hurricane Agnes Category 1 Tropical Storm 1972 June 22, 1972
Tropical Storm Carrie Tropical Storm Tropical Storm 1972 September 3, 1972
Subtropical Storm Alfa Tropical Storm Subtropical Storm 1973 July 30, 1973
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Hurricane Belle Category 3 Tropical Storm 1976 August 10, 1976
Tropical Storm Henri Tropical Storm Tropical Depression 1985 September 23, 1985
Hurricane Gloria Category 4 Category 1 1985 September 27, 1985
Tropical Storm Chris Tropical Storm Tropical Depression 1988 August 29, 1988
Hurricane Bob Category 3 Category 2 1991 August 19, 1991
Hurricane Bertha Category 3 Tropical Storm 1996 July 13, 1996
Hurricane Floyd Category 4 Tropical Storm 1999 September 16–17, 1999
Table 2. 21st century (http://en.wikipedia.org/wiki/List_of_New_England_hurricanes) So far in the 21st century four tropical cyclones have made landfall in New England. The first was Tropical Storm Hermine in 2004 which affected
southeastern Massachusetts with minimal damage. In 2006 Tropical Storm Beryl struck Nantucket, again with minimal damage. Tropical Storm
Barry in 2007 made landfall as a remnant extratropical storm which caused heavy rainfall and flooding. In 2009 Tropical storm Danny made landfall
in New England as an extratropical storm.
Storm Category
Season Date of landfall Peak intensity Intensity at landfall
Tropical Storm Hermine Tropical Storm Tropical Storm 2004 August 31, 2004
Tropical Storm Beryl Tropical Storm Tropical Storm 2006 July 21, 2006
Tropical Storm Barry Tropical Storm Extr. Storm 2007 June 4, 2007
Tropical Storm Danny Tropical Storm Extr. Storm 2009 August 29, 2009
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Figure 3. Northeast hurricanes since 1950 (http://www.msnbc.msn.com/id/12839865/ns/weather/t/ready-or-not-northeast-ripe-big-
hurricane/#.UJ_CnIbqSmQ).
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Figure 4. Google Earth image of the New York area. Upper two arrows show locations of coastal inlets that narrow and cause increase in height of
local sea level associated with the storm surge from a hurricane. Lower arrow shows location of the barrier island off the New Jersey coast that was
the site of severe damage to houses and other structures during hurricane Sandy.
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Figure 5. Google Earth image of a housing area built out into the bay (“back” side of the barrier island) near Ship Bottom, New Jersey. The houses
are just 1-2 m above seal level.
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Figure 6. Google Earth image of the Loveladies, (Long Beach Island), New Jersey area showing many housing areas built out into the bay and
illustrating the large number of houses at low elevation and near the coast. Note that the North direction is to the upper right in this rotated image.
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Figure 7. USGS topographic map (1952) of the Loveladies, (Long Beach Island), New Jersey area (upper right on the map) in 1952. Note that the
area of dense housing in the Google Earth image (Figure 6) was not developed until after 1952. Existing buildings in 1952 are noted by small black
squares. The topographic contours shown on the map indicate that the majority of the land area shown is less than 3 m (10 ft) above sea level.
Photos (below, Figures 8, 10, 12, 14, and 16) of the New Jersey coastal town of Mantoloking, just north of where Hurricane Sandy made landfall,
taken on October 31, 2012 shows the damages caused by Hurricane Sandy
(http://www.nasa.gov/mission_pages/hurricanes/archives/2012/h2012_Sandy.html). Credit: Aerial photography courtesy of the NOAA Remote
Sensing Division. Similar-area Google Earth images from before Sandy are shown (below) in Figures 9, 11, 13, 15, and 17.
11
Figure 8. NOAA aerial photograph (close-up) of damage from hurricane Sandy to houses on the barrier island north of the coastal town of
Mantoloking, New Jersey. See Figure 9 for similar-area Google Earth image from before the hurricane. House A is located on both this Figure and
Figure 9 for reference. The original high resolution photo can be viewed at
http://www.nasa.gov/mission_pages/hurricanes/archives/2012/h2012_Sandy.html.
A
12
Figure 9. Google Earth image (from before hurricane Sandy) of similar area as the aerial photograph shown in Figure 8.
A
13
Figure 10. NOAA aerial photograph (close-up) of damage from hurricane Sandy to houses on the barrier island north of the coastal town of
Mantoloking, New Jersey. See Figure 11 for similar-area Google Earth image from before the hurricane. House B is located on both this Figure
and Figure 11 for reference. The original high resolution photo can be viewed at
http://www.nasa.gov/mission_pages/hurricanes/archives/2012/h2012_Sandy.html.
B
14
Figure 11. Google Earth image (from before hurricane Sandy) of similar area as the aerial photograph shown in Figure 10.
B
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Figure 12. NOAA aerial photograph (close-up) of damage from hurricane Sandy to houses on the barrier island north of the coastal town of
Mantoloking, New Jersey. See Figure 13 for similar-area Google Earth image from before the hurricane. House C is located on both this Figure
and Figure 13 for reference. The original high resolution photo can be viewed at
http://www.nasa.gov/mission_pages/hurricanes/archives/2012/h2012_Sandy.html.
C
16
Figure 13. Google Earth image (from before hurricane Sandy) of similar area as the aerial photograph shown in Figure 12.
C
17
Figure 14. NOAA aerial photograph (close-up) of damage from hurricane Sandy to houses on the barrier island north of the coastal town of
Mantoloking, New Jersey. See Figure 15 for similar-area Google Earth image from before the hurricane. House D is located on both this Figure
and Figure 15 for reference. The original high resolution photo can be viewed at
http://www.nasa.gov/mission_pages/hurricanes/archives/2012/h2012_Sandy.html.
D
18
Figure 15. Google Earth image (from before hurricane Sandy) of similar area as the aerial photograph shown in Figure 14.
D
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Figure 16. NOAA aerial photograph (close-up) of damage from hurricane Sandy to houses on the barrier island north of the coastal town of
Mantoloking, New Jersey. See Figure 17 for similar-area photograph from before the hurricane. House E is located on both this Figure and Figure
17 for reference. The original high resolution photo can be viewed at
http://www.nasa.gov/mission_pages/hurricanes/archives/2012/h2012_Sandy.html.
E
20
Figure 17. Aerial photograph (from before hurricane Sandy; http://www.nasa.gov/mission_pages/hurricanes/archives/2012/h2012_Sandy.html) of
similar area as the aerial photograph shown in Figure 16.
E
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Figure 18. This TRMM rainfall analysis indicates that the heaviest rainfall totals of greater than 260mm (10.2 inches) were over the open waters of
the Atlantic Ocean. Rainfall totals of over 180mm (~ 7 inches) are also shown over land in many areas near the Atlantic coast from New Jersey to
South Carolina. Hurricane Sandy's track over the Atlantic Ocean is shown overlaid on this analysis in white. Credit: SSAI/NASA, Hal Pierce
(http://phys.org/news/2012-11-nasa-hurricane-sandy-rainfall-space.html).
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Figure 19. Tide gage record for The Battery, New York showing the hurricane Sandy local storm surge sea level (red symbols). Note that the
observed sea level is the sum of the normal tide (blue line and the surge (residual, green line). Because the maximum surge occurred
(coincidentally) during high tide, it was larger than if it had occurred during normal or low tide. From:
http://www.washingtonpost.com/blogs/capital-weather-gang/post/hurricane-sandy-recap-historic-storm-from-storm-surge-to-
snow/2012/10/31/9a7c56d8-2362-11e2-ac85-e669876c6a24_blog.html.
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Figure 19. Google Earth image of The Battery, New York City, New York.