06 Jun 2013

As Extreme Weather Increases, Bangladesh Braces for the Worst

Scientists are predicting that warming conditions will bring more frequent and more intense extreme weather events. Their warnings hit home in densely populated Bangladesh, which historically has been hit by devastating sea surges and cyclones.
By brian fagan

Melting ice sheets, calving glaciers and rising sea levels: scenarios of impending inundation fill the news, while climate change skeptics assure us that these are long-term problems, part of the natural cycle of things. One thing is certain: These are multi-decade changes in a warming world, which we’re tempted to leave to future generations.

But as Hurricane Katrina and Superstorm Sandy forcibly reminded us here in the United States, warming brings more extreme weather events — and the catastrophic inundations that accompany them. In the short term, destructive and very expensive sea surges are the most immediate consequence of rising sea levels. And nothing provides a more sobering reminder of our vulnerability than the awesome cyclones that often accompany these surges in Bangladesh.

Bangladesh lies at the head of the Bay of Bengal, the world’s largest river delta formed by the Ganges, Brahmaputra, and Meghna rivers. Water covers some 10,000 square kilometers of the country, most of which lies close to sea level. An arabesque of waterways large and small cuts through
Between 1947 and 1988, 13 severe cyclones ravaged the lowlands of Bangladesh, killing thousands.
the coastal plain. In the past, a unique mosaic of beach and tidal forests, as well as dense mangrove swamps, acted as a cushion against sea surges and cyclones. Two hundred years ago, more than 11,000 square kilometers of mangrove swamps and forests protected the coast. But today, this natural coastal barrier is under threat from promiscuous forest clearance for agricultural land, from shrimp farming, and from the construction of barrages for irrigation works. Most natural coastal protection is gone.

Cyclones and their fearsome sea surges descend on Bangladesh with a furious intensity that has killed millions of people over the centuries. Between 1947 and 1988 alone, 13 severe cyclones ravaged the lowlands, causing thousands of deaths and sweeping away villages and defensive embankments. 1970’s Cyclone Bhola brought winds as high as 185 kilometers an hour. At least half a million people died, as well as a million head of cattle. More than 400,000 houses vanished. Forty-six thousand fishermen perished.

Bhola affected over three-and-a-half million people with various degrees of severity. This catastrophe moved the Bangladesh government and international agencies to organize networks of volunteers, build cyclone shelters, and develop evacuation plans — strategies that have saved countless lives in recent years.

Monsoon floods Bangladesh
Jewel Samad/AFP/Getty Images
A mother and child on the outskirts of Dhaka, after monsoon floods.
What will happen in the future, if, as scientists are predicting, warmer conditions bring stronger and more frequent cyclones, and Himalayan glaciers far to the north melt faster and swell the great rivers hundreds of kilometers downstream? Most of Bangladesh lies on the fertile alluvial plains of the Ganges and Brahmaputra rivers. Would conventional flood works provide a solution?

Expensive international schemes proposed by the World Bank envisage building nearly 8,000 kilometers of dikes to control the rivers, at a cost of $10 billion, but many local farmers oppose the scheme because it would result in forced changes to their farming methods. Nor would massive dikes like those in the Netherlands solve the problem, for the subsoil is alluvial sand and mud, which shifts constantly. In any case, Bangladesh lacks the funds to pay for such expensive projects.

The best solutions appear to lie with the people themselves and with judicious government investments in infrastructure and flood-protected housing. Numerous farmers are building houses on stilts that stand above even the most severe floods. There are smaller-scale solutions as well, among them simple dwellings built on half-meter concrete plinths to support dwellings with inexpensive jute panel walls that are easily replaced after a flood.

At the same time, CARE and other organizations are encouraging Bangladeshi farmers to use long-abandoned agricultural methods that include floating gardens, which are well suited to areas that are flooded for
For many Bangladeshis, there remains but one option — to move away completely.
long periods of time. Bamboo and dense beds of hyacinth, as well as last year’s decomposed vegetation, allow the growth of vegetables for sale in markets for most of the year. Salt-resistant rice varieties are another solution, as they are fast-growing crops that can be harvested before the monsoon rains arrive. A policy of breaching earthen dikes to encourage silt deposition as the water drains away helps the land rise and counters the effects of rising sea levels.

An estimated 17 to 40 million people in Bangladesh will be affected if current projections of the effects of sea level rise become reality. As the land is gradually lost to rising salinity and the ocean, with no prospect of recovery, there remains but one option for many Bangladeshis — to move away completely. The effects are somewhat akin to those experienced by small, low-lying islands like the Maldives or Tuvalu in the Central Pacific. In the case of Tuvalu, however, you are looking at somewhere around 10,000 out-migrants. Bangladesh has tens of millions of potential refugees, under circumstances where there is effectively nowhere for people to resettle.

Monsoon floods Bangladesh
Adi Shah/AFP
A rickshaw ride on a flooded street in Dhaka following monsoon rains.
People in the threatened areas of Bangladesh are in quadruple jeopardy because they have limited income sources, low resilience, and, above all, little capacity for adaptation, especially when, as is the case, population growth is rapid and there is great disparity in the distribution of wealth and livelihoods.

Traditionally, people from rural villages have moved to the capital of Dhaka and other cities to seek employment. However, in Bangladesh, which is one of the world’s most densely populated countries, cities and towns are already bursting at the seams, and there are few job opportunities. Given the slow nature of the environmental changes taking hold there, it’s likely that both internal and external migration will be voluntary and, at first, on a relatively small scale. It’s when the pressure increases decades from now that political and security problems will mount, especially in a country surrounded by neighbors, primarily India, with whom relations are at times tense.

The problem is by no means unique to Bangladesh. Globally, an estimated 200 million people live within five meters of sea level, including many in megacities. Shanghai, one of the world’s great cities, lies at or near sea level. The city is subsiding, and the authorities there are investing in sea defenses; but they also persist in filling in low-lying coastline for more development. Florida, with its shoreline high-rises, spends millions on coastal defenses, which are, at best, temporary palliatives in the face of destructive sea surges. Dubai’s government has invested in artificial islands in the Gulf region, which are largely delusional hubris in the face of rising sea levels. It is only a matter of time before a truly epochal disaster destroys large tracts of a coastal megacity and tens of thousands die.


In Low-Lying Bangladesh,
The Sea Takes a Human Toll

In Low-Lying Bangladesh, The Sea Takes a Human Toll
Living on shifting land formed by river deltas, the people of Bangladesh have a tenuous hold on their environment, with cyclones buffeting coastal zones and rising seas posing a looming threat. But, as this e360 video from 2010 makes clear, many Bangladeshis already are suffering as a growing population occupies increasingly vulnerable lands.
Cyclones and storm surges are nothing new in human experience. What is new is the extent of damage they can cause in a densely populated coastal world and the enormous numbers of people affected by them, often catastrophically.

The impending crisis is not just a Bangladeshi problem but also one that affects us all — for it will. We should remember Article 2.1 of the United Nations Covenant, which gives all a right to a ”means of subsistence.” Rising sea levels and their consequences threaten that right in Bangladesh and elsewhere.

The defense strategy of last resort — managed resettlement not for thousands, but for millions — may move to the front burner. At present, there are no international policies for dealing with the involuntary population movements caused by climate change. But there’s no question that they will be needed within a generation or two. The sooner we start thinking about the problem, the better.


Brian Fagan is Emeritus Professor of Anthropology at the University of California, Santa Barbara, and author of the recently published The Attacking Ocean: Sea Levels Past, Present, and Future. His other books include The Great Warming: Climate Change and the Rise and Fall of Civilizations.

SHARE: Tweet | Digg | | Reddit | Mixx | Facebook | Stumble Upon


Dear Prof. Fagan: What a pleasure to find you writing for e360. Thank you for the information packed essay on the human ecology of the Ganges Brahmaputra region. I will use your essay in my classes (along with the fascinating books of yours that I already use). BTW, my friends and I use your cruising guides for sailing to So Cal waters from SF Bay. Regards, Don

Posted by Don Strong on 06 Jun 2013

As the evidence in the article points out, the frequency of tropical cyclones in Bangledesh was higher during the cooler period between 1947 and 1988. Activity has dropped off significantly since, with only 1 cyclone (non-severe) since 1998. A similar trend is occurring throughout the rest of the world, with tropical cyclones in a relative lull over the past several years. Tornadic activity in the U.S. is also near an all-time low. Severe tornadoes have been decreasing since the relative high decades of the 1950s and 60s.

Posted by Daniel on 07 Jun 2013

Very interesting and informative post Brian Fagan.

Climate change poses significant risks for Bangladesh. The impacts of higher temperatures, more variable precipitation, more extreme weather events, and sea level rise are already felt in Bangladesh and will continue to intensify. The impacts result not only from gradual changes in temperature and sea level but also, in particular, from increased climate variability and extreme events, including more intense floods, droughts, and storms.

It is predicted that climate change could have devastating impact on agriculture. Agriculture is a key economic driver in Bangladesh, accounting for nearly 20 percent of the GDP and 65 percent of the labor force. The performance of this sector has considerable influence on overall growth, the trade balance, and the level and structure of poverty and malnutrition. Moreover, much of the rural population, especially the poor, is reliant on the agriculture as a critical source of livelihoods and employment.

The impacts of climate change could affect agriculture in Bangladesh in many ways:

- The predicted sea-level rise will threaten valuable coastal agricultural land, particularly in low-lying areas.
- Biodiversity would be reduced in some of the most fragile environments, such as Sundarbans and tropical forests.
- Climate unpredictability will make planning of farm operations more difficult.

The effects of these impacts will threaten food security for the most vulnerable people of Bangladesh. The country’s agriculture sector is already under stress from lack of productivity and population growth. Any further attempt to increase productivity will likely to add pressure to available land and water resources.

These changes are already having major impacts on the economic performance of Bangladesh and on the lives and livelihoods of millions of poor people.

Various models predict the nations vulnerability. Bangladesh is the most vulnerable nation due to global climate change in the world according to German Watch’s Global Climate Risk Index (CRI) of 2011. This is based on the analysis of impacts of major climate events that occurred around the world in the twenty year period since 1990. The reasons are complex and extremely intertwined. Located at the bottom of the mighty GBM river system (Ganges, Brahmaputra and the Meghna) there are a total of 57 trans-boundary rivers coming down to it 54 from neighbouring India and 3 from Myanmar. The country which has no control of the water flow and volume drains to the Bay of Bengal over 90 percent of the total run-off generated annually. Coupled with the high level of widespread poverty and increasing population density, limited adaptive capacity and poorly funded, ineffective local governance has made the region one of the most adversely affected in the planet. There are an estimated one thousand people in each square kilometre with the national population increasing by 2 million people each year.

By 2020, anywhere from 500- 750 million people are projected to be affected by water availability due to climate change around the world. Low-lying coastal regions, such as Bangladesh are vulnerable to the Sea level rise and increased occurrence of intense, extreme weather conditions such as the cyclones from 2007–2009. In most countries such as Bangladesh, yields from rain fed agriculture could be reduced to 50 percent by 2020. And for a country with increasing population and hunger, this will have an extremely adverse effect on food security. Although effects of climate change are highly variable, by 2030, South Asia could lose 10 percent of rice and maize yields, while neighbouring states like Pakistan could experience a 50 percent reduction in crop yield.

As a result of all this, Bangladesh would need to prepare for long term adaptation, which could be as drastic as changed sowing dates due to seasonal variations, introducing different varieties and species, to practicing novel water supply and irrigation systems. In essence, we
have to identify all present vulnerabilities and future opportunities, adjusting priorities, at times even changing commodity and trade policies in the agricultural sector while promoting training and education throughout the masses in all possible sphere.

Dr. A. Jagadeesh Nellore (AP), India

Posted by Dr.A.Jagadeesh on 08 Jun 2013

Cyclone and hurricane frequency.

Recent trends in cyclone and hurricane frequency are no reason for decreased concern about these powerful storms. We have now and will continue to have plenty of them (ca 87/yr on average (Frank, W. M., and G. S. Young (2007), Frank&Young, 2007. The interannual variability of tropical cyclones, Mon. Weather Rev., 135, 3587–3598, doi:10.1175/).

The devastation suffered by shore dwelling people is certainly not abating, “Philippine Death Toll Rises in Worst Cyclone in Three Years”

Time series records of hurricanes are short, but there is no indication that their current frequency is not within long-term historical ranges. Emmanuel, K 2010. J. Adv. Model. EarthSyst., Vol. 2, Art. #1, 12 pp.

In some areas, frequency has increased greatly,

Recent decreases in frequency are part and parcel of ENSO fluctuations, and when the El Nino conditions return, the frequency will increase. (Accumulated Cyclone Energy, ACE), “considerable variability in tropical cyclone ACE is associated with the evolution of the character of observed large-scale climate mechanisms including the El Nino Southern Oscillation and Pacific Decadal Oscillation. In contrast to record quiet North Pacific tropical cyclone activity in 2010, the North Atlantic basin remained very active by contributing almost one-third of the overall calendar year global ACE.” Maue, R. N. 2011. Geophysical Research Letters 38, L14803

Posted by Don on 09 Jun 2013

The North Atlantic and North Pacific are typically out of sync with regards to tropical cyclone activity. The frequency of Atlantic hurricanes is greater during La Nina years, such as this year. This has been the case for the past several years. But remember, the Pacific contributes much more in accumulated cyclone energy than the Atlantic. Even though the Atlantic has generated more storms in recent years, fewer have become major storms, and none have hit the coast of North America since Felix came ashore in Nicaragua in 2007.

Posted by Daniel on 10 Jun 2013

Daniel: Indeed, indeed. I lived thorough Gulf Coast in Hurricanes during the 1990s. One would be
incautious not to expect more intense storms to return when ENSO shifts.

Posted by Don on 10 Jun 2013

All of science agrees: “Climate change is real and is happening and could lead to unstoppable warming.”

Wouldn’t REAL planet lovers WANT the scientists to end the debate by saying it “will be” a crisis instead of delaying CO2 mitigation with 28 more years of just “could be” a crisis? How close to the point of no return from unstoppable warming will science lead us before they take their own crisis seriously?

Not one single IPCC warning says it WILL be a crisis.
Not one single IPCC warning is NOT swimming in maybes.
Science can end the debate instantly by saying their crisis will happen, not just might happen.

Posted by David Nutzuki on 13 Jun 2013


Of course, we all would love to see something definite. However, we have not reached that stage yet. Hence, we are presented with several potential scenarios, depending on which factor exert the greatest influence. Of course, if we ever do resolve the debate, then the amount of money spent researching the "crisis," will dry up, and we can proceed to whatever mitigation efforts are deemed necessary.

Posted by Daniel on 14 Jun 2013

Great article regarding information about Bangladesh flood. I am a research student of disaster management in Pakistan. it will help me to explore my findings...
Posted by Muhammad Naseem Akhtar on 04 Mar 2015

What about the position of West Bengal coastal area and Kolkata?
Posted by Dr.Abhijit Ghose on 30 May 2015



How Far Can Technology Go To Stave Off Climate Change?
With carbon dioxide emissions continuing to rise, an increasing number of experts believe major technological breakthroughs —such as CO2 air capture — will be necessary to slow global warming. But without the societal will to decarbonize, even the best technologies won’t be enough.

Republican Who Led EPA Urges Confronting Trump on Climate
William K. Reilly, a Republican and one-time head of the EPA, is dismayed that a climate change skeptic has been named to lead his former agency. But in a Yale e360 interview, he insists environmental progress can be made despite resistance from the Trump administration.

The Legacy of the Man Who Changed Our View of Nature
The 19th-century German scientist Alexander von Humboldt popularized the concept that the natural world is interconnected. In a Yale e360 interview, biographer Andrea Wulf explains how Humboldt’s vision helped create modern environmentalism.

A Drive to Save Saharan Oases As Climate Change Takes a Toll
From Morocco to Libya, the desert oases of the Sahara's Maghreb region are disappearing as temperatures rise and rainfall decreases. Facing daunting odds, local residents are employing traditional water conservation techniques to try to save these ancient ecosystems.

An Unusually Warm Arctic Year: Sign of Future Climate Turmoil?
This year will almost certainly go down as the warmest on record in the Arctic, with autumn temperatures soaring 36 degrees F above normal. In a Yale e360 interview, climatologist Jennifer Francis explains why a swiftly warming Arctic may have profound effects on global weather.


Donate to Yale Environment 360