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Cyclone Nargis death toll may top 100,000

By: Dr. Jeff Masters, 1:58 PM GMT on May 08, 2008

The tragedy of Cyclone Nargis' aftermath in Myanmar continues to intensify, with the top U.S. diplomat in the county now predicting a death toll of 100,000. A death toll of 80,000 has been estimated by a local official in just one district of the country--Labutta--so the death toll may go much higher than 100,000. Although the first major U.N. relief flight of emergency supplies has finally landed, the criminal indifference of the nation's leaders towards the plight of the cyclone's survivors will doom hundreds or thousands more to death or terrible suffering. One can only hope that the people of Myanmar will rise up and put an end to Myanmar's dictatorship as a result of this awful tragedy.

There is historical precedent for this sort of occurrence. The deadliest tropical cyclone of all time, the Great Bhola Cyclone of 1970, killed upwards of 550,000 people is what was then called East Pakistan (and now called Bangladesh). A statement released by eleven political leaders in East Pakistan ten days after the cyclone hit charged the government with "gross neglect, callous indifference and utter indifference". They also accused the president of playing down the news coverage. The dissatisfaction with the government response to the disaster boiled over into full-fledged civil war the next year, which ultimately led to the overthrow of the government and the establishment of the new nation of Bangladesh. As bad as the West Pakistani response to the Great Bhola Cyclone of 1970 was, the response of the Myanmar government to Nargis is far worse. The slowness of response to this tropical cyclone disaster is unprecedented in modern times.

Nargis is one of the 20 deadliest cyclones in history
Cyclone Nargis' official death toll of 22,500 ranks the storm as the 19th deadliest in world history. Fourteen of the world's twenty deadliest cyclones have been Bay of Bengal storms. Until Nargis, these storms have all affected Bangladesh and India. The bay's shallow bathymetry and low-lying, heavily populated river deltas make the Bay of Bengal the world's most notorious tropical cyclone graveyard. If Nargis's death toll does exceed 100,000, the storm will still only rank as the tenth deadliest tropical cyclone of all time.


Figure 1. This pair of images from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite use a combination of visible and infrared light to make flood waters obvious. Water is blue or nearly black, vegetation is bright green, bare ground is tan, and clouds are white or light blue. On April 15 (top), rivers and lakes are sharply defined against a backdrop of vegetation and fallow agricultural land. The Irrawaddy River flows south through the left-hand side of the image, splitting into numerous distributaries known as the Mouths of the Irrawaddy. The wetlands near the shore are a deep blue green. Cyclone Nargis came ashore across the Mouths of the Irrawaddy and followed the coastline northeast. The entire coastal plain is flooded in the May 5 image (bottom). The fallow agricultural areas appear to have been especially hard hit. For example, Rangoon (Yangon), the capital city with population over 5 million, is almost completely surrounded by floods. Several large cities (population 100,000-500,000) are in the affected area. Muddy runoff colors the Gulf of Martaban turquoise. Image credit: NASA Earth Observatory.

Nargis' storm surge
Nargis took the worst possible path, tracking right along the low-lying, heavily populated Irrawaddy River delta. Moreover, the storm hit at high tide, greatly increasing the impact of the storm surge. Tidal range in the Irrawaddy River delta is about five feet between low tide and high tide, and the death toll would have been much, much lower had the storm hit at low tide. Further amplifying the storm surge's height was the fact that Nargis was moving rather slowly--about 11 mph. Slow moving tropical cyclones can drive a much higher storm surge into narrow estuaries that connect to the ocean, since there is more time for the surge to penetrate inland. Nargis' track, forward speed, and high tide timing created a "perfect storm" able to cause an unprecedented storm surge in the Irrawaddy River delta. The only saving grace was the relatively small size of the cyclone.

I talked to Stephen Baig, the National Hurricane Center's storm surge expert, about Nargis. He confirmed that the surge from Nargis was likely about 12 feet, and that had Myanmar asked, NHC would have happily made them custom storm surge forecasts for the storm. He offered that NHC would do the same for any country in need of storm surge forecasts for an approaching storm.

Human factors helped make the storm surge worse. About 80% of the mangrove forest along Myanmar's coast has been destroyed, to make room for rice paddies and shrimp farms. Mangroves--tall, gnarly, salt-tolerant trees--act to blunt and slow down the progress of the storm surge and reduce the wave action of the ocean. Had more mangroves been left to survive, the impact of the storm surge would have been lessened. How much so, no one can say, for there are few observations of the storm surge to verify models of this. Keep in mind that the mangroves are far more effective in protecting against a sudden, powerful wave like the 2004 tsunami, than the slower, hours-long inundation of a storm surge.

Comments from Chris Burt
I've been in regular communication about this disaster with Chris Burt, author of the excellent book Extreme Weather. He has been visiting Myanmar every year for 30 years, and has much insight on the situation there:

Yet another official Chinese news agency has gone on record about the disaster, going so far as to quote the U.S Chief of Mission (the top ranking US diplomat in Myanmar since we have had no ambassador in the country for 30 years now):

http://news.xinhuanet.com/english/2008-05/08/content_8127548.htm

Again, I can tell you that this is VERY significant. China is Myanmar's only real friend in the world and when THEY begin to publish critical reports, I really am now starting to think this dreadful regime in Myanmar has met its match.

Here is a letter I received from a friend in the capital city, Yangon today:

Dear Chris,

Help received within the country is insufficient and inefficient. We need so much of outside professional, efficient help. NOT in three days. SHOULD be in three hours. Should have been in the last three days. Why are they waiting for three more days? We cannot risk any more life. The dead toll is shockingly too high and it is increasing minute by minute. Please keep me posted with international support. I will also keep you posted.


Great Plains storm chasing
Wunderblogger Mike Theiss is in Tornado Alley this week, performing his annual chase efforts. Be sure to catch his spectacular photos of the amazing storms that form over our Great Plains.

Jeff Masters
Tornado Damage 2
Tornado Damage 2
Damage from today's Tornado in Windsor, Colorado

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.