Putting Haiyan's Storm Surge in a Global Context

Super Typhoon Haiyan generated a catastrophic storm surge that devastated coastal communities in the provinces of Samar and Leyte, in the Eastern Visayas region of the Philippines. As photos and videos stream in from the hardest hit areas, it appears as though the height of this surge may rival the 7.3-meter (24 foot) surge generated by the Typhoon of Samar and Leyte, on October 12, 1897. Until now, the 1897 surge event was the highest official storm surge height in the Philippines and all of East Asia, according to SURGEDAT, a global storm surge data center.

The high-water pattern in the 1897 event was quite different, however, as that storm tracked farther to the north. Therefore in 1897, the highest water marks occurred in eastern Samar, near the community of Hernani. During that storm the highest water marks near Tacloban, the epicenter of Haiyan’s surge, were approximately 4.9 meters (16 feet), near the community of Basey. It therefore appears as though Haiyan’s surge was considerably higher than the 1897 storm surge in northern portion of San Pedro and San Pablo Bay, near Tacloban.

Haiyan may have generated the highest modern-day storm surge level in all of East Asia.

Image: BBC Breaking News/ AFP

In a global context, Haiyan’s storm surge was the highest surge since Hurricane Katrina generated a 8.47-meter (27.8-foot) surge along the Mississippi Coast in the United States, in August, 2005. Haiyan’s surge is also the first surge to exceed 5 meters since Tropical Cyclone Yasi generated a 5.33-meter (17.5-foot) surge at Cardwell, Queensland in Australia, in February, 2011.

The world's largest storm surges have consistently occurred along the Bay of Bengal, particularly in India and Bangladesh. At least three surge events in this region have exceeded 12 meters (39.4 feet), the largest of which was a 13.7-meter (45-foot) storm tide that struck Bangladesh in 1876 (Dube et al. 1997). Although Haiyan's surge was likely smaller than these world record holders, images and videos from Tacloban depict a city that has been obliterated by a severe catastrophe.

 Haiyan generated the highest global storm surge level since Hurricane Katrina in August, 2005.

Image: NOAA (see: http://www.katrina.noaa.gov/helicopter/helicopter-2.html)

Unfortunately, Haiyan’s surge inflicted many fatalities. Various media sources indicate that 10,000 people may have died in the city of Tacloban alone. By comparison, Hurricane Katrina killed 1,833 people (McTaggart-Cowan et al. 2008), many of whom drowned in the storm surge.

However, we cannot say that Haiyan’s surge is the most deadly since Katrina, because Tropical Cyclone Nargis generated an extremely dangerous storm surge in Myanmar during May, 2008. Although Nargis’ peak storm surge was only approximately 4.5 meters (Fritz et al. 2011), approximately half the height of Katrina's surge, Nargis flooded a dense population that was largely unprepared. This storm inflicted an extraordinary number of fatalities, as 146,000 people died in this storm (Fritz et al. 2011), many of whom drowned in the storm surge. It is likely that Haiyan has generated the deadliest storm surge since Nargis.

Haiyan's surge may be deadliest since Tropical Cyclone Nargis killed 146,000 in Myanmar in 2008.

Image: http://davidkiyokawa.com/blog/?p=2859

The scale of Haiyan's impact be similar in some ways to the 2011 Japan Tsunami, which killed approximately 15,000 people and left 8,000 people still missing as of June, 2011 (Jaffe et al. 2011). Damage and destruction in the worst-hit areas looks comparable, as entire neighborhoods have been completely swept away. Despite the horrific scenes coming out of the Philippines, the scale of this catastrophe is still smaller than the 2004 Indian Ocean Earthquake and Tsunami, which inundated coastlines from East Asia to Africa and killed approximately 228,000 people (United States Geologic Survey 2008).

References

Dube, S.K., A.D. Rao, P.C. Sinha, T.S. Murty, N. Bahulayan, 1997: Storm surge in the Bay of Bengal and Arabian Sea: The problem and its prediction. Mausam, 48, 283-304.

Fritz, H.E., C. Blount, S. Thwin, M.K. Thu, and N. Chan, 2010b: Cyclone Nargis Storm Surge Flooding in Myanmar’s Ayeyarwady River Delta. Published in Charabi, Y., Indian Ocean Tropical Cyclones and Climate Change. Published by Springer Science and Business Media.

Jaffe, B., B. Richmond, and H. Gibbons, 2011: International Team Studies Tsunami Deposits in Japan to Improve Understanding and Mitigation of Tsunami Hazards. Sound Waves, Coastal and Marine Research News from Across the USGS. Published by the United States Geologic Survey. Available on the Web at: http://soundwaves.usgs.gov/2011/06/SW201106-100.pdf.

McTaggart-Cowan R., G.D. Deane, L.F. Bosart, C.A. Davis, T.J. Galarneau, Jr., 2008: Climatology of tropical cyclogenesis in the North Atlantic (1948-2004). Monthly Weather Review, 136, 1284-1304.

United States Geological Survey, 2008: Largest and Deadliest Earthquakes by Year, updated July 16, 2008. Published on the Web at: http://earthquake.usgs.gov/earthquakes/eqarchives/year/byyear.php.

"The Water Was as High as a Coconut Tree"

Details are emerging about the devastating storm surge generated by Super Typhoon Haiyan in the Philippines. The images and videos streaming in from the provinces of Samar and Leyte in the Eastern Visayas are truly horrific.

Tropical Cyclone Haiyan (Yolanda) produced a catastrophic storm surge that leveled much of Tacloban, the capital of Leyte Province. 
Image: Bullit Marquez/ AP

A quick recap on the storm:

Super Typhoon Haiyan slammed into the Philippine provinces of Samar and Leyte on Friday, November 8, 2013, with catastrophic wind speeds and a massive storm surge. The cyclone made landfall near the city of Guiuan with an estimated wind speed of 195 MPH.

According to Jeff Masters’ Weather Underground Blog, such intense winds are the strongest in modern history as a tropical cyclone made landfall (Masters 2013). The former record was held my Hurricane Camille, which struck the Mississippi Coast in the U.S. back in 1969. His page ranks the cyclones with the highest sustained wind speeds, and reveals that three of five strongest storms at landfall hit the Philippines. Super Typhoons Zeb and Megi, which struck in 1998 and 2010, respectively, and produced sustained wind speeds of 180 MPH at landfall, and are tied for 4^th place on the list.

Super Typhoon Haiyan generated winds of approximately 195MPH at landfall, breaking a world record. These winds generated a massive storm surge that leveled much of Tacolban, in Leyte Province. 
Image: Buzz Feed News

Although the wind damage is extraordinary, eyewitnesses are reporting that a massive, quick-moving storm surge was responsible for much of the devastation. Tacloban City, the provincial capital of Leyte Province, appears to be ground zero for this storm surge catastrophe.

Haiyan's storm surge moved rapidly, tearing through much of Tacloban City in Leyte Province. 
Image: News Breaker; AFP/ Getty Images

Here’s what we know about the surge:

• ·      The height of the storm surge was extraordinary. Soon after the surge event, CNN was reporting surge height as high as the second story on buildings (CNN, 2013).

• ·      Others used landmarks as a measuring stick for surge height. Sandy Torotoro, a 44-year old pedicab driver, stated, “The water was as high as a coconut tree,” (Philstar, 2013). Some of the most riveting photos from Tacloban City show entire neighborhoods demolished, with just a few coconut trees remaining upright.

• ·     The surge came in very quickly. Some described it as a wall of water, and many were apparently surprised by the swift-moving surge. Philstar provides one eyewitness account of a local resident who was swept away by the surge. “One Tacloban resident said he and others took refuge inside a parked jeepney to protect themselves from the storm, but the vehicle was swept away by a surging wall of water.” (Philstar, 2013)

• ·      The surge was high enough to float large ships and tankers, and deposit them in neighborhoods of Tacloban City. Such images resemble the destruction wrought by catastrophic tsunamis, such as the 2004 Indian Ocean Tsunami, or the 2011 Japan Tsunami.

Haiyan's storm surge was high and powerful enough to float ocean-going tankers and deposit them inland. 
Image: Aaron Favila/ AP.

As more photographs and video become available from the impacted area, the maximum height of this storm surge should become more evident. At the moment it appears that Haiyan’s storm surge height may rival the 7.3-meter (24 foot) surge that struck the Philippine provinces of Samar and Leyte in 1897. That storm surge drowned 1,300 people, as it produced the highest surge in the modern history of the Philippines and all of East Asia.

Haiyan's storm surge deposited this ship in a Tacloban neighborhood. 
Image: Aaron Favila/ AP

Although Haiyan’s storm surge may be comparable to the 1897 storm, the death toll will certainly be much higher. Many media sources are now indicating that 10,000 people may have died in Tacloban City alone, and thousands are still missing.

References:

CNN, 2013:

http://www.cnn.com/2013/11/09/world/asia/philippines-typhoon-haiyan/index.html?hpt=hp_t1

Masters, 2013: http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2576

Philstar, 2013:

http://www.philstar.com/headlines/2013/11/11/1255305/10000-dead-missing

Coastal Configuration Played a Key Role in Tacloban's Massive Storm Surge

Tropical Cyclone Haiyan generated a massive and destructive storm surge in portions of the Philippines. One of the worst hit areas was Tacloban, where the water levels reached the second story on some buildings, according to CNN. (link: http://www.cnn.com/2013/11/09/world/asia/philippines-typhoon-haiyan/index.html?hpt=hp_t1)

Images and videos now depict classic storm surge destruction, like upended cars and vans that were floated by the massive wall of water. Paula Hancocks, a CNN correspondent, indicated that she saw evidence of much water damage and the destruction was similar to what she has seen in massive tsunamis. (see video link above).

Upended cars are a classic sign of a massive storm surge or tsunami inundation. As water floats vehicles, the front part containing the engine is heavier and will sink, causing the back end of the car to rise. As a result cars appear upended. Such sights were common during Hurricane Katrina, and are seen again today in Tacloban, Philippines. Image: CNN (http://www.cnn.com/2013/11/09/world/asia/philippines-typhoon-haiyan/index.html?hpt=hp_t1)

Tacloban was located at a very vulnerable location for storm surge during Haiyan. The center of Haiyan's circulation passed to the south of this coastal city, enabling strong onshore winds to funnel water into San Pedro and San Pablo Bay. The shape of the bay magnified the surge levels, as the bay narrows near the north end. Displaced water doesn't just disappear, and when water gets funneled into narrow bays and inlets it has nowhere to go but "up", spilling out onto the land and causing much devastation.

Tropical Cyclone Haiyan (Yolanda) tracked just south of Tacloban City. After the eye of the storm passed to the southwest of the city, very intense winds from the southeast pushed a massive storm surge into the area. Image: Matthew Pace (https://twitter.com/DrMatt12News/status/399018637391953921/photo/1)

Coastal configuration, or the shape of coastal bays and inlets, often enhances surge levels in the Philippines. Maps of the island nation show numerous bays and inlets. While such coastal shapes often enhance surge levels, they also create very localized surge levels. For example, at the narrow portion of a bay, water levels may reach 5 meters (16.5 feet), while water levels may just be 2 meters (6.56 feet) a few miles away.

Coastal configuration enhanced storm surge levels near Tacloban City, Philippines. Strong southeasterly winds funneled a large storm surge into the north portion of San Pedro and San Pablo Bay, which created a wall of water two stories high in Tacloban City. Image: Hal Needham

Coastal shape and configuration is one reason why Pass Christian, Mississippi, has observed the highest two storm surges in U.S. history. This location observed an 8.47-meter (27.8 foot) surge from Hurricane Katrina in 2005, and a 7.5-meter (24.6 foot) surge from Hurricane Camille in 1969. Water tends to funnel into Bay St. Louis and get trapped, causing it spill out on the land. Unlike the Philippines, water levels in coastal Mississippi are also enhanced by very shallow offshore water depth, or bathymetry.

Tropical Cyclone Haiyan is now a category-3 cyclone headed towards Vietnam. It should impact Vietnam and portions of extreme southern China with strong winds and elevated water levels.

SURGEDAT is currently under expansion, as we are adding many new events from East Asia to our database. Our historical research is now finding many surge events in China, Japan, the Philippines and Vietnam. The database should be updated next spring, as we submit a paper on historical global storm surge observations and impacts.

Haiyan's Surge May Have Been Highest in East Asia History

Tropical Cyclone Haiyan slammed into the Philippines today, likely generating the most intense wind speeds at landfall of any tropical cyclone in recorded history, according to the Weather Underground. Jeff Master's blog stated, "Haiyan had winds of 190 - 195 mph at landfall, making it the strongest tropical cyclone on record to make landfall in world history." It appears as though Haiyan's intensity may have eclipsed the former record held by Hurricane Camille, which struck the Mississippi Coast of the United States in 1969.

 Tropical Cyclone Haiyan generated incredible winds exceeding 190MPH at landfall as it slammed into the island of Samar in the Philippines. Image Source: McIDAS.

It's very possible that Haiyan generated the highest storm surge in the history of East Asia, however, it will take time to measure the high water marks. The highest storm surges in East Asia have occurred in the Philippines, as the archipelago experiences frequent strikes from intense tropical cyclones.

Although we are looking into reports of a 10 meter (32.8 foot) surge that may have impacted the Philippines in 1968, at the moment the highest confirmed surge event in East Asia was a 7.3-meter (24 foot) storm tide that struck the Philippines in 1897 (Arafiles et al. 1978) . This cyclone, called the Typhoon of Samar and Leyte, struck on October 12, 1897, generated a peak water level at Hernani and Tanglad. Hernani is located just north of Haiyan's landfall, and would have experienced very intense onshore winds during Haiyan. The storm tide from the 1897 cyclone killed 1,300 people.

Tropical Cyclone Haiyan impacted the same area as the Typhoon of Samar and Leyte (1897), which generated the highest verifiable storm surge in the history of East Asia and drowned 1300 people. Image:  AFP PHOTO/CHARISM SAYAT/AFP/Getty Images

An interesting aspect of many Philippine storm surges is that coastal shape and configuration tends to play an important role for generating very localized surge events. This is because the Philippines is an archipelago of islands, many of which have large inlets and bays. Water tends to funnel into these areas, causing very high storm surge levels, while locations just a few miles away may observe relatively low water rises.

Take the 1897 surge event, for example. Storm surge levels varied greatly over relatively short distances, mostly because of coastal configuration. Arafiles and Alcances (1986) state, “The observed surge was 7.3 meters (24 ft.) above mean sea level at Hernani and Tanglad, Samar and the water level remained at this height for about two hours. This unusual height of the observed surge was to some extent magnified by the coastal configuration. In comparison, Pambuyan, which is better protected and had a rise of only 1.5 meters (4.9 ft.) while Guiuan, only 0.7 meters (2.3 ft.). Again to illustrate the effects of coastal topography, Basey had an observed surge of 4.9 meters (16 ft.) while Tacloban only 0.4 meters (1.3 ft.). It will be noted that there were many instances when coastal configuration played a vital role in further magnifying the total storm tide.”


Such history comes to life now, as Tropical Cyclone Haiyan has struck this same area. Haiyan made landfall on Samar, near Guiuan, and areas such as Hernani, which observed the highest storm tide levels in 1897, where located north of Haiyan’s track, and likely also observed very high water levels today. The 1897 cyclone shows us that this area has the potential to observe a surge of at least 7 meters (23 feet), and given Haiyan’s incredible intensity, we must wonder if some locations observed surge levels on par with the 1897 storm. The most positive aspect about Haiyan is that the forward speed of this story was relatively fast. Slower moving cyclones tend to build up higher storm surges.

 

Massive waves crash into the shoreline near Legazpi City, Philippines (Image: AP Photo/Nelson Salting)

A regional comparison shows that the highest surges in the Philippines have been larger than in other countries of East Asia. China’s highest storm surge was 5.94 meters (19.5 feet) at Nandu Tide Gage in 1980, while Japan’s highest storm surge occurred in the Isewan Typhoon (Vera) of 1959, when the water level reached 3.5 m (11.5 feet).

SURGEDAT has identified 113 storm surge events in East Asia, through the 2012 season. More than 25 of these events occurred in the Philippines, however, we’re still completing this dataset. Look for an updated global dataset to be uploaded to our website next spring, while we submit a paper on global storm surge observations and impacts.

The Southern Impact Planning Program (SCIPP) has funded the development of SURGEDAT, as SCIPP conducts stakeholder-driven research related to weather and climate hazards that impact six states in the South Central U.S. SCIPP has conducted much research and outreach related to storm surge, as this hazard has severely impacted the U.S. Gulf Coast. The global SURGEDAT database enables SCIPP to conduct data-driven research, such as investigating how tropical cyclone (hurricane) characteristics impact storm surge heights. Including international events in the database provides more comprehensive data and analysis, which ultimately will improve storm surge models.

How High Was Phailin's Storm Surge?

How high was Phailin's storm surge? Some storm surge observations from different locations are just starting to be reported, but it may be days or weeks or until we have a full assessment of maximum surge levels.

Tropical Cyclone Phailin generated a large storm surge and destructive waves along the coast of India. Image source: http://www.abc.net.au/news/image/5018642-3x2-940x627.jpg

That said, a few observations are just starting to come in...

An article from the BBC states...

"The Times of India reported that a storm surge more than 3m (9ft) high had inundated areas of Ganjam, Khurda, Puri and Jagatsinghpur districts of Orissa and the Srikakulam district of Andhra Pradesh." See: http://www.bbc.co.uk/news/world-asia-india-24510464

Also, the closest INCOIS tide gauge, located in Paradeep, which is well east of the area of peak surge, has reported surge levels exceeding one meter. The graphic below provides water levels from the past 24 hours. The top graphic depicts observed water levels (dots) compared to astronomical tide levels (if there were no storm). The difference between these two levels is essentially a storm surge, and often called a residual, on such graphs.

Note that between 0900 and 1000 UTC, some residual levels exceeded 1.5 m. However, these high values may include some wave action, so they may not be purely storm surge levels.

Observed water levels vs. astronomical tide levels for the past 24 hours at Paradeep, India. Source: http://tsunami.incois.gov.in/ITEWS

Residual water levels from the past 24 hours at Paradeep, India. These levels represent the difference between observed water levels and astronomical tide levels, and essentially represent storm surge observations. Source: http://tsunami.incois.gov.in/ITEWS

Please send any storm surge observations from this storm to me by:

1) Replying to this or other blog posts

2) Sending me a tweet at @hal_needham

3) Emailing me at hal@srcc.lsu.edu

Thank you so much and stay safe, everybody!

-Hurricane Hal

Phailin Made Landfall as a Category-4 Tropical Cyclone; Onshore Hurricane-Force Winds Still Generating a Massive Surge

Tropical Cyclone Phalin made landfall on Oct 12 around 1330 UTC, or about 1900 local time. A wind profile produced by NOAA at 1200 UTC, just before landfall, placed the maximum sustained winds at the time of landfall around 122 knots, or 140 MPH, which made the storm a category-4 tropical cyclone at landfall.

A NOAA wind profile map indicates Phailin was a category-4 tropical cyclone just before landfall. Source: http://www.ssd.noaa.gov/PS/TROP/mtcswa.html?storm=IO022013&id=PHAILIN&timeDiff=6

Although the center of circulation is now over land, the storm continues to generate hurricane-force winds that are blowing onshore to the east of the circulation center. This is certainly continuing to pile up storm surge along the coast near and to the east of Gopalpur. Storm surge inundation often lasts for many hours, especially if strong onshore winds persist.

The map below depicts wind profiles as of 1800 UTC. The contour lines show wind speed in knots. The area shaded in yellow contains wind speeds of greater than 35 knots, or approximately 40 MPH (tropical storm strength), while the area within the 65-knot contour is essentially experiencing hurricane force winds in excess of approximately 74 MPH.

As of 1800 UTC, Phalin's center of circulation is inland, but hurricane-force winds continue to blow onshore, perpetuating coastal flooding east of Gopalpur. Source: http://www.ssd.noaa.gov/PS/TROP/mtcswa.html?storm=IO022013&id=PHAILIN&timeDiff=0

Phailin Approaches Landfall near the Orissa/ Andhra Pradesh Border

Tropical Cyclone Phailin is approaching landfall near the border of Orissa and Andhra Pradesh. Track the movement of the eye on Brian McNoldy's radar website at: http://andrew.rsmas.miami.edu/bmcnoldy/tropics/radar/

Tropical Cyclone Phailin approaches landfall, as seen on this radar image from Brian McNoldy at the Univ of Miami

Expect the highest storm surge levels to occur to the northeast of the point of landfall. The region of peak surge will most likely extend from Ichchapuram to Puri, however, coastal flooding will occur along the coast for hundreds of kilometers. Surge levels may be particularly high near the coastal community of Gopalpur, east of Brahmapur.