Cyclone!

I promised to pass on the story told to me on the beach of the Bay of Bengal by the postdoc from Orissa. First of all it's worth noting that Orissa is one of the least-developed regions of India and that to encounter a PhD scientist from Orissa, especially from the rural areas as was this man, is a rare event, representing a striking example of social mobility that would at one time have been unheard of in India.

Along the northern end of the Bay of Bengal, the coastal regions of Burma, Bangladesh, West Bengal, and Orissa form a continuous strip of very similar, heavily populated land, some tens of km wide. much of it no more than ten meters in elevation above high tide. The land is intensively cultivated, and in many regions there is little by way of forest or other buffer zone to protect a village from whatever cyclones the Bay of Bengal should brew up. I know very little by way of meteorology, so BadMom should jump in with a correction, but a cyclone is very much like a hurricane. My understanding is that cyclones are huge, circular tropical storms, and that hurricanes are a subset of cyclones -- if a cyclone is large enough, and has the good fortune to have been born in the gulf of Mexico, Caribbean Sea, or the waters off the eastern coast of the Americas, then it gets to call itself a hurricane. The cyclones that roar up out of the Bay of Bengal are by definition, then, not hurricanes, but the largest of the Bengal cyclones can put to shame even a Class V hurricane (think Katrina, Rita, Mitch, Gilbert, or if you're old enough, Camille).


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Half a million people died in the 1970 cyclone that hit what is now Bangladesh. Cyclones that kill 10,000 or more happen several times per decade. In a later post I'll talk about what makes cyclones so lethal in these parts, but for now, here is what the postdoc told me:

The 1999 Orissa cyclone had sustained winds over 250 km/hr, gusts to 300 km/hr. The winds and the low-pressure eye drove a storm surge (increase in sea level height) estimated to be in excess of 8 m. Storm surges are not like a momentary big wave that can be blocked by a a few rows of trees. They are a sustained increase in the depth of the water along the coast line. In the event of an 8 m surge, if you are taking shelter in a single-story house built on ground 5 meters above sea level (as could be true even if you live even 20 km or more from the coast) and if the tallest sturdy piece of furniture in your house is 1 m tall, and if you yourself are 1.5 m tall, then (5+1+1.5<8) either you drown or you take your chances on your open roof, in 250 km/h winds (if your roof hasn't blown off).

The postdoc was a teenager in 1999, and with his family was fortunate to live in a house on higher ground, so that at its peak the water rose only to the height of one meter above the floor of their single-story house. He and his family spent in total 36 hours in water. They had the foresight to bring the family cow inside as the storm arose. Unsheltered cows mostly died, as did birds by the millions. The postdoc spoke of how, as the storm came in, it was frightening but also thrilling to see the power of the winds, with birds slamming into the walls of their house and falling instantly dead. It was exciting to peek out the window and see trees topple. First the power went out, but still their battery-powered radio brought weather updates until (as they learned only later) the transmission towers blew over. When the water came in, he got very cold and the storm became less interesting. When the winds calmed and the waters receded, the family went outside and were astonished to have clear lines of sight in every direction, it seemed like forever. The winds had simply flattened many smaller trees, and most of the houses. Their neighbors lived mostly in bamboo-framed, thatch-roofed dwellings, and many of his neighbors had been killed. There was no way to cook rice, and the rest of their food had been spoiled by the filthy water, liquid cholera. But with the coconut trees blown down, there were coconuts by the tens of thousands lying around everywhere you looked. Tightly sealed against impurity, the coconuts' wholesome milk and delicate flesh was all the family had to eat or drink for three days, until at last the helicopters arrived to drop emergency supplies.

The postdoc said that he had had a relatively easy time of it compared to his friend who was earning his living as a fisherman, living some kilometers closer to the coast. His friend heard the warnings a day or so in advance, and knew of the risk, but was tired of evacuating for false alarms and so he and a number of other young men decided to stay put and ride it out. But this was no false alarm, and the waters in this village rose to much deeper than one meter, covering (or knocking over) all the buildings in the village. The friend with eight other men climbed trees to escape the rising water. The wind blew the leaves off the trees, and then it blew the clothes off the men. Some of the men lost their strength, fell into the water, and drowned. When the winds eased, there were only three men left, but the waters were still too deep to stand. The other two men, tired of clinging to branches, climbed down into the waters, but there they eventually drowned. Our postdoc's friend was the only remaining man, and he was determined to wait until the waters fully receded. Eventually they did, but when he tried to climb down, he fainted. (I speculate it was the effect of blood rushing back into his long-cramped limbs). He fell to the ground, breaking his leg. He lay there naked in the mud for some uncertain length of time. He was rescued by some returning villagers who set out to collect and dispose of corpses, but found one man alive. His leg eventually healed, according to my Orissan narrator.