Friday, August 1, 2014

Field Teams Collect Valuable Storm Surge Data

Last autumn, Super Typhoon Haiyan made landfall in the Philippines with maximum sustained winds of 195 mph. This was the most intense tropical cyclone at landfall on record (Masters 2014). Haiyan generated a massive storm surge that devastated the city of Tacloban, and other locations in the Eastern Visayas region of the Philippines. This catastrophic storm surge enabled Haiyan to kill at least 6,300 people (National Disaster Risk Reduction and Management Council), although the death toll may be as high as 8,000 (Aon Benfield 2014).

 Super Typhoon Haiyan generated a catastrophic storm surge that killed thousands of people last year in the Philippines. Photo: Noel Celis/AFP/Getty Images

Following Haiyan’s surge, Hurricane Hal’s Storm Surge Blog featured a series of photos provided by Aslak Grinsted, an assistant professor at the Center for Ice and Climate, Niels Bohr Institute, in Copenhagen, Denmark. These photos depicted people standing in a parking lot in front of trees with bark removed at approximately 2.5 – 3.0 human heights. After featuring these photos on the November 14, 2013 post, a Filipino man living in the United Kingdom wrote to me and identified the location of those photos as the parking lots adjacent to Tacloban Airport. Once the location was identified, I was able to estimate an approximate storm tide height of 6.5 m (21.33 ft) in this location. In this way, international collaboration occurred between people living in Denmark, the United Kingdom and the United States, which provided some of the first estimates of Haiyan’s storm surge height.

Although such collaboration provided a quick estimate of Haiyan’s storm surge height, observations provided by field work teams can help provide an extensive network of accurate high water marks. Such networks are essential for understanding localized flood patterns, particularly in areas with a limited amount of tide gauges or with localized flood patterns. Post-storm surge field work teams may observe evidence of high water levels through different methods. Some of the most common methods include observing high water marks or mudlines inside or outside buildings, as well as observing the height of rafted debris, damage trimlines or tree bark removal.

Hermann Friz, an associate professor of civil engineering at the Georgia Institute of Technology (Georgia Tech), has led several field projects to record high water marks following high-profile coastal flooding events. He has conducted field work both in the U.S. and abroad, including locations such as the U.S. Gulf Coast, and coastal locations in the countries of Oman and Myanmar.

Multiple trees on Ship Island, Mississippi, provided similar heights of tree bark removal, which revealed maximum water levels from Hurricane Katrina. Photo provided by Hermann Fritz.

Along the U.S. Gulf Coast, Fritz led a team to collect high-water marks in Louisiana, Mississippi, Alabama and Florida, in 2005, following Hurricane Katrina (Fritz et al. 2008). The team produced a unique dataset with 153 data points in these states. More than one-third of these observations were obtained on barrier islands, so this dataset is useful for validating both onshore and offshore surge heights. These high-quality data provide the latitude, longitude and height of high water, as well as the type of observation, such as mudline inside a building, tree bark removal, damage trimline or rafted debris.

A 7.65-m (25.1 ft) rod does not quite reach the height of tree bark removal on East Ship Island, Mississippi, following Hurricane Katrina. The tree bark removal at this site extended to 8.2 m (26.9 ft), indicating an extraordinarily high storm surge at this location. Photo provided by Hermann Fritz.

Damage trimline elevations on structures along coastal Mississippi reveal high water marks from Hurricane Katrina. Photo provided by Hermann Fritz.

In 2007, Fritz and a field team collected high water marks in Oman, on the Arabian Peninsula, following the passage of Tropical Cyclone Gonu, the most intense tropical cyclone on record in the Arabian Sea (Fritz et al. 2010). The team collected 25 high-water marks, which provide the location and water height, as well as the type of observation. Such work provides a pioneering effort that will be useful for validating storm surge models in a region that observes relatively few tropical cyclones and has sparse recorded data. This field team observed that relatively steep bathymetry along some sections of coastline decreased storm surge heights, but increased wave magnitudes.

Photo and quote taken from Fritz et al. (2010). Direct quote: Wadi flooding due to discharge and storm surge induced backwater at Muscat (Photo credit: Department of Meteorology, Sultanate of Oman).

In 2008, Fritz and a team of researchers constructed a storm surge dataset in Myanmar, following Tropical Cyclone Nargis, which killed more than 138,000 people (Fritz et al. 2009). The storm surge peaked at over 5 m (16.5 ft) near the landfall location, and storm surge inundation traveled inland more than 50 km (31 miles). This team took on quite an adventure, as they encountered poisonous snakes, and had to avoid areas that might be infested with saltwater crocodiles. The extent of coastal erosion in this area was perhaps best depicted by a golden Buddhist stupa, which was originally built on land, but was seen 150 m (492 ft) offshore.

Hermann Fritz and a team of researchers collected high water marks in coastal Myanmar, following Tropical Cyclone Nargis in 2008. Note the Buddhist Stupa protruding from the water in the upper left of this image, approximately 150 m (492) offshore. This structure was originally build on land. Photo provided by Hermann Fritz. 

Various other organizations have deployed field teams to collect storm surge data during the past decade. The Federal Emergency Management Agency (FEMA) is a government agency in the U.S. that has conducted outstanding field work. FEMA has contracted URS Group, Inc. to collect data in Louisiana, Mississippi and Alabama following Hurricane Katrina. They completed three reports, which provide more than 1,000 high water marks (URS 2006a; URS 2006b; URS 2006c). FEMA also provides nearly 400 observations from Hurricane Ike’s storm surge in Texas and Louisiana (Federal Emergency Management Agency 2008). FEMA used such observations to construct surge elevation contour maps, which estimate maximum surge heights along the coast. For example, see:

Regional overview map for Hurricane Katrina's surge elevation contour maps, which are provided for each of the green squares. The area in yellow depicts the inundation zone. These maps are based upon the surveyed coastal high water mark elevations. Source: FEMA.


Aon Benfield, 2014: Annual Global Climate and Catastrophe Report. Available at:
Federal Emergency Management Agency, 2008: Hurricane Ike in Texas and Louisiana. Mitigation Assessment Team Report. Available on the web at:
Fritz, H.M., C. Blount, R. Sokoloski, J. Singleton, A. Fuggle, B.G. McAdoo, A. Moore, C. Grass, and B. Tate, 2008 : Hurricane Katrina Storm Surge Reconaissance. Journal of Geotechnical and Geoenvironmental Engineering, 134, 5, 644-656.
Fritz, H.M., C.D. Blount, S. Thwin, M.K. Thu, and N. Chan, 2009 : Cyclone Nargis storm surge in Myanmar. Nature Geoscience, 2, 448-449.
Fritz, H.M., C.D. Blount, S. Thwin, M.K. Thu, and N. Chan, 2009 : After the Storm. Backstory in Nature Geoscience, 2, 528.
Fritz, H.E., C. Blount, F.B. Albusaidi, and A.H.M. Al-Harthy, 2010: Cyclone Gonu Storm Surge in the Gulf of Oman. Published in Charabi, Y., Indian Ocean Tropical Cyclones and Climate Change. Published by Springer Science and Business Media.
Masters, J., 2014: Super Typhoon Haiyan: Strongest Landfalling Tropical Cyclone on Record. Dr. Jeff Masters’ Blog on Weather Underground, posted November 7, 2013. Available on the Web at:
National Disaster Risk Reduction and Management Council, 2014: NDRRMC Update: Updates re the Effects of Typhoon “YOLANDA” (HAIYAN). Republic of the Philippines, Quezon City, Philippines. Report issued April 17, 2014. 2 pp. Available on the Web at:
URS, 2006a: Final Coastal and Riverine High Water Mark Collection for Hurricane Katrina in Mississippi. Prepared by URS Group, Inc. for the Federal Emergency Management Agency. Final edition completed March 14, 2006. Available at:
URS, 2006b: High Water Mark Collection for Hurricane Katrina in Louisiana. Prepared by URS Group, Inc. for the Federal Emergency Management Agency. Final edition completed March 30, 2006. Available on the web at:
URS, 2006c: High Water Mark Collection for Hurricane Katrina in Alabama. Prepared by URS Group, Inc. for the Federal Emergency Management Agency. Final edition completed March 3, 2006. Available on the web at:

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