Monitoring Storm Tide from Hurricane Sandy along the coast ... · Monitoring Storm Tide from...
Transcript of Monitoring Storm Tide from Hurricane Sandy along the coast ... · Monitoring Storm Tide from...
Thomas P. Suro, P.H., CFM Hydrologist/ Engineer Act. Surface-water Specialist U.S. Geological Survey New Jersey Water Science Center
Monitoring Storm Tide from
Hurricane Sandy
along the coast of New Jersey
Photos courtesy of The Roosevelts, Orig. published 11-2-2012.
May 22, 2013 NJ Water Monitoring Council Meeting
Monitoring Storm Tide from
Hurricane Sandy
• Background on USGS coastal-monitoring program.
• Storm history for Hurricane Sandy.
• USGS sensor deployment and recovery.
• High-water mark flagging and surveying.
• Results from Hurricane Sandy documentation.
Monitoring Storm Tide from Hurricane Sandy
Past Storm-Sensor Deployment
• USGS studies effects of hurricanes and tropical
storms to better understand potential impacts on
coastal communities and habitats.
• Current storm-surge sensor deployment program
began in 2005 after Hurricane Katrina.
• USGS deployed sensors for: Rita (2005) Wilma
(2005) Ernesto (2006) Gustav (2008) Ike (2008) Earl (2010) Irene (2011) Isaac (2012) Sandy (2012)
Cat. 2 – Oct. 25
Begins to re-intensify to Cat. 1 – Oct. 28
Begins transition to
post-tropical
• Eighteenth named storm of 2012 season; tenth hurricane of season.
• Formed as a tropical disturbance on Oct. 18, named on Oct. 22 (Tropical Storm), reached peak intensity on Oct. 25 (Cat 2 Hurricane).
• Center of Sandy makes landfall near Atlantic City, NJ at around 7 P.M. on October 29th with 90-mph winds.
• Prior to landfall storm began transformation to a post-tropical cyclone.
• Gale- to storm-force winds from Sandy, lasting 12 to 18 hours caused major to record coastal flooding along the coast of New Jersey on October 29, 2012.
Monitoring Storm Tide from Hurricane Sandy Storm History and Deployment
Low – Oct 18 TS – Oct 22
Landfall near Atlantic City
Oct. 29
• Predicted unprecedented track, post-
tropical transition, and massive wind field (fetch), prompted USGS toward deployment.
• Sensor deployment needs to be decided at least 4 days before predicted landfall.
• By October 24 most NHC models predicted landfall along northern mid-Atlantic or Northeast coast.
• On October 25th USGS consults with
NWS and NHC and a decision was made to deploy.
Monitoring Storm Tide from Hurricane Sandy Storm History and Deployment
Oct. 25 – Decision made to deploy
Oct. 26 – Sensor deployment begins
Oct. 28 – Sensor
deployment complete
Oct. 29 - Landfall
• Sensors deployed by USGS along east coast from Virginia Beach, VA to Portland, ME. • 230 storm-tide sensors, • 65 barometric-pressure sensors, • 9 wave-height sensors, • 8 rapid-deployment gages, and • 921 HWM’s flagged.
• More than 14 local USGS offices and 2 storm-surge coordination centers directly involved.
• Development of online mapper to display real-time data and storm-tide elevation to NAVD88 within days of storm.
• A coordination challenge !
Monitoring Storm Tide from Hurricane Sandy East Coast Deployment
Monitoring Storm Tide from Hurricane Sandy
Data Collection and Sensor Recovery
• USGS operates 23 continuous-tide gages in NJ.
• USGS also has 32 tidal crest-stage gages in NJ.
• The USGS also operates 6 streamgages in Barnegat bay
• 10 storm surge sensors were deployed in NJ prior to Sandy.
• Highest Peak storm-tide elevations recorded in Raritan Bay.
> 13 ft
> 9 ft
> 7 ft
Monitoring Storm Tide from Hurricane Sandy
Data Collection and Sensor Recovery
• More than 900 high-water marks (HWMs) flagged along the east coast.
• About 620 were surveyed (Conn, Mass, and RI not surveyed due to lack of funding)
• In NJ 170 marks were collected and surveyed from Bergen to Cape May counties.
• HWMs verified recorded peak storm-tide elevations and added valuable information in all of NJ’s coastal counties
12-14 ft
9-11 ft (waves 17- 19 ft)
6-9 ft
Monitoring Storm Tide from Hurricane Sandy
Peak storm tide data
• USGS tide gage network not designed for hurricane monitoring.
• Data estimated when peak tide levels exceeded maximum recordable limits.
• HWM data collected to verify peak storm tide elevations at USGS gages and along the entire coast.
Monitoring Storm Tide from Hurricane Sandy
Peak storm tide data
• Peak storm tide elevations greater than 12 ft recorded in and around Raritan Bay.
• Peak storm tide elevations generally 8-12 ft from Sandy Hook to Toms River.
• Peak storm tide elevations generally 6-8 ft south of Atlantic City.
Note: Peak storm tide was recorded by tide gages, surge sensors and wave sensors.
Monitoring Storm Tide from Hurricane Sandy
Flood extent and inundation
• USGS tide gages, storm sensors, and HWM data were used to calibrate flood extents.
• The USGS worked in cooperation with FEMA, NJDEP and NJDOT to develop a documentation plan for extent of flooding.
Raritan Bay had highest storm tide
Sandy Hook completely inundated
SeaBright peak 2 ft. greater than 1992
Atlantic City worst flooding since 1962
Monitoring Storm Tide from Hurricane Sandy
Comparison to previous storms
• Hurricanes in the northeast have been recorded back to the 1600’s.
• In 1893 back to back August hurricanes hit NJ and the northeast.
• In Sept. 1938 the Great New England Hurricane passed along the NJ coast and made landfall on Long Island.
• In Sept. 1944 “The Great Atlantic Hurricane” hit New Jersey much worse than the 1938. (winds of 60-70 MPH with gusts > 80-90 MPH) NOTE: Second year of hurricane reconnaissance : B25 used to fly into the storm.
• The March 1962 storm was the most widespread and devastating to hit the region during that century. (Named the “five-high” storm because of five consecutive high tides.)
• The December 1992 “ Great Nor’easter” was a slow-moving nor’easter that produced record setting storm tides at most USGS tide stations along the coast at New Jersey and New York. (only exceeded by 1962 storm in a few locations)
“Sandy” was not the first major Hurricane to Hit New Jersey and the northeast.
Monitoring Storm Tide from Hurricane Sandy
Comparison to previous storms
Sta No. Sta. Name March 1962 (ft. NAVD 88)
Dec. 1992 (ft. NAVD 88)
Aug 2011 (ft. NAVD 88)
Oct 2012 (ft. NAVD 88)
“Sandy”
01406700 Ratitan River at Perth Amboy, NJ
-- 9.41 7.82 13.4
01407600 Shrewsbury River at Sea Bright, NJ
5.61
7.31
6.29
9.56
01409135 Barnegat Bay at Loveladies, NJ
4.83 4.23 2.84 5.01
01409285 Little Egg Harbor at Beach Haven, NJ
5.91 5.67 3.60
7.47
01410100 Mullica River at Port Republic, NJ
6.61 5.86 3.77 8.1
Note: some HWM’s from 1962 show 7-10+ ft peak storm-tide elevations south of AC to Cape May.
Monitoring Storm Tide from Hurricane Sandy
Summary of data
• USGS data is being used by FEMA to verify flooding. (Sandy elevations generally 0.5 to >3 ft higher than previous record)
• USACE and NWS have access to the data for storm tide/surge modeling. (Peak storm-tide pattern for Sandy was similar to 1992 but different than 1962)
• State and local government can use the data to verify flood prone areas and inundation, peak storm-tide elevations etc.. (USGS data for “Sandy” available at nj.usgs.gov – click link for “Information on Hurricane Sandy”).
• The USGS is also trying to work with the Natural and Cultural Resources group at FEMA and representatives from other government agencies including NPS and USACE on the topics of coastal restoration and monitoring.
What does this mean?
“Sandy” reset the current standard for preparedness. New Jersey has been battered by hurricanes in the past, so we need to better prepare for the future.
Monitoring Storm Tide from Hurricane Sandy
Access to data and reports
Initial USGS storm tide monitoring report available : http://pubs.usgs.gov/of/2013/1043
USGS Scientific Investigation Report for New Jersey is in progress….
http://water.usgs.gov/floods/events/2012/sandy/sandymapper.html
http://nj.usgs.gov