How Bangladesh adapts to erosion, floods, and rising seas

Where do people go when the water takes their land? Guided by a three-year ETH Zurich study and first-hand voices, we trace a pattern that defies the headlines: most climate migration is short and local, driven by community ties, scarce resources, and the will to stay near what remains.

If you would like to find out more about the climate challenges in Bangladesh and read the collection on climate solutions, and more stories, please visit Swissinfo Science.

Journalist: Giannis Mavris 

Host: Jo Fahy

Audio editor: Michele Andina
Distribution and Marketing: Xin Zhang

SWI swissinfo.ch is a public service media company based in Bern, Switzerland. 

Transcript

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Setting The Scene In Dhaka

Jo Fahy 0:00

Swissinfo podcasts.

Jan Freihardt 0:04

I visited Dhaka, that's the capital of Bangladesh. Bangladesh is already today one of the countries most affected by climatic changes. We always see it as a looking glass into the future of what might happen in other world regions.

Jinat Hossain 0:18

I saw flood since I was a child, right?

Jan Freihardt 0:21

Sometimes entire villages get washed away in just a few weeks.

Jinat Hossain 0:25

We grew up seeing that people are struggling and people are tackling these emergencies and they are building their own strategy.

Jan Freihardt 0:32

We definitely need to start researching also how can we live in a world where climatic conditions are changing very rapidly.

Giannis Mavris 0:39

The problem specific to the South is salinity.

Jinat Hossain 0:42

There are a lot of external people coming to do shrimp aquaculture, and they are high class, and then the people who cannot farm they become poorer and they become the labor of these high-class people.

Jo Fahy 1:11

A recent study on Bangladesh by Switzerland's Federal Institute of Technology offers some surprising answers. With more than 170 million people, Bangladesh is one of the most densely populated countries in the world. Apart from cyclones, the country regularly faces severe droughts and occasional flooding. That's partly because of higher rainfall and partly because of the glacial melt in the Himalayas, both of which make Bangladesh's approximately 800 rivers as well. So, what does climate migration in this country look like? And how could it be a role model for what's to come in other areas of the world? Our reporter, Yanis Mavris, looked into this story and visited Bangladesh recently. And Yanis joins me on the podcast today.

Giannis Mavris 2:28

Hello, Joe.

Jo Fahy 2:29

Hi Giannis, thanks for joining us. Could you tell us about what you found out while you were out in Bangladesh?

Giannis Mavris 2:34

Yes, uh, well, I visited Dhaka, that's the capital of Bangladesh. There I met Salme, a widow who lives with her son in a run-down house in Korail, which is one of the largest slans in Dhaka and home to around 50,000 people. She moved to find work in nearby Gulshan, which is the affluent business district of Dhaka. The same applies to Shah Jahan, who also lost his land on the island of Bola. He now lives with his wife and their seven children on a piece of land that technically

Bangladesh As Climate Looking Glass

Giannis Mavris 3:05

belongs to the government. This situation is difficult for him, as he told me, and I'm quoting, we are at their mercy, they could evict us at any time. Shah Jahan is a cook, but he can no longer work because he injured his arm. People relocating from the island or from any other place to the big city after a natural disaster, that is nothing unusual. However, and that is the interesting thing, it occurs far less frequently than commonly believed. I spoke about this to Jan Freihard, who is a researcher at the Federal Institute of Technology, the ETH Zurich, who studied climate-driven migration in Bangladesh for over four years.

Jan Freihardt 3:43

I felt early on that climate change is already a reality today, so we definitely need to start researching also how we can live in a world where climatic conditions are changing very rapidly. Bangladesh was the focus of our research because it's already today one of the countries most affected by climatic changes. We always see it as a looking glass into the future of what might happen in other world regions in the upcoming decades. Many of these processes are already unfolding in Bangladesh today. So, in that sense, it's a good case study to study adaptation to climatic changes and potentially what we can learn for other world regions as well.

Giannis Mavris 4:28

So, Bangladesh is kind of a role model for climate migration. And according to Ban Ki-moon, the former UN Secretary General, Bangladesh is actually a global pioneer in preparing for climate changes. The country has almost 9 million people living abroad, which makes it one of the countries with the highest amount of international migrants in the world. That migration, of course, is linked to many different reasons like work, education, marriage, family reunification. When it comes to climate change, though, Freihardt observed that people tend to migrate within the country.

Jan Freihardt 5:09

Most people migrate within the country, and that's also the case in Bangladesh. We conducted our study along the Jamuna River, which is one of the three main big rivers in Bangladesh. So Bangladesh in total has around 8 to 900 rivers. It's one of the most, on the one hand, densely populated country, but also very densely traversed by a lot of rivers, one of the biggest river deltas in the world. So basically there's water and rivers everywhere. And we studied in particular the Jamuna because it has a lot of riverbank erosion and flooding that is occurring each year during the monsoon season between June and September. This erosion and flooding are the two environmental changes that we picked for our study as a case study to understand what people do if they lose their house and their belongings and potentially also their agricultural land due to the erosion. Because the erosion, maybe also there to give some context, it's happening on a different scale than what we might be used from from Europe, where of course rivers also have some erosion, but usually it's maybe a few centimeters each year, maybe on severe years 10-20 centimetres. But in Bangladesh, it can really be in along this Jamuna River, maybe two-three hundred meters in just a few weeks, because the soil is very sandy, so it has very little resistance to the flow of water when it increases during the monsoon.

Lives Upended By River Erosion

Jan Freihardt 6:40

And so that basically means that sometimes entire villages get washed away in just a few weeks.

Giannis Mavris 6:47

So there are many different reasons for migrating. It's not an easy task to find out what the influence of climate change on migration numbers and patterns are.

Jan Freihardt 6:55

We picked around 36 villages along this Jamuna River, and then over time, with the upcoming monsoon season, some of these villages they were affected by erosion and some were not. And that setting basically allows us then later on, in a statistical sense, to compare how many people moved in the villages that were not affected. And let's say there we maybe find, I just now say a random number, let's say 10% of people moving. And then in the treated villages, those that have experienced erosion, maybe 13 or 14% migrate. And then these differences, 3 to 4 percentage points. This is then now the effect of erosion and flooding on migration. But the study went far beyond numbers for statistics. So we had a large team of Bangladeshi students, and we conducted a study over a time period of three years between 2021 and 2024, and once a year traveled to the villages to interview our 2200 respondents. Once people started moving, that's of course where it becomes, on the one hand, interesting, but also tricky to find them and took a lot of effort on the side also of our team and students who really invested a lot of energy in traveling to the new home of our respondents to interview them there. And so we now have a three-year history basically of these 2,200 people, how their lives evolved, both in terms of whether they were affected by erosion and flooding, and also whether they moved or not, and if they moved, where to, and how then their lives evolved, both in economic sense, but also in terms of whether they're happy or not, whether they're satisfied with their lives. And then also in between these in-person surveys, we had shorter phone surveys every six to eight weeks to also get a fine-grained understanding of when does movement happen during the monsoon, because that's often the also very challenging period in the villages when the flood water comes and there's maybe half a meter of water in the villages. It's very difficult for people to maintain their daily life. You can imagine there's sometimes even water in the houses, so they have to shift all the belongings to storage space below the roof, but then cooking gets more and more difficult, etc.

Jo Fahy 9:16

At this point, we should say that these kind of environmental changes along the Jamuna are not primarily climate-driven. They happen to a great part due to the geological situation. The monsoon seasons are also a natural pre-climate change phenomenon. However, climate change also has an impact. It changes the monsoon patterns, leading to heavier rain during the monsoon season, but less during the dry season. And it also melts the glaciers in the Himalayas, which feed the Jamuna River.

Giannis Mavris 9:46

Exactly. That's also what Jan Freihart pointed out to me. Still, Bangladesh is an ideal case study for him since it shows what happens to people when their land at homes get washed away. And that's something other parts of the world will have to face as sea levels rise, and of course the coastal erosion that comes with that.

Jo Fahy 10:04

So what did the researchers find out?

Giannis Mavris 10:07

Well, Freihart told me that the findings were actually a bit of a surprise to them.

Jan Freihardt 10:12

Starting the study, we had this hypothesis, okay, when people lose their land, they just pack their things and they move to the next city, or maybe even to the capital, Dhaka. But in our case we observed a very different pattern that actually many people or most of our people who had lost their house and their land, they stayed within the village. So they maybe just shifted two, three hundred meters inland, they took whatever they could still save before the erosion happened, basically dismantled the house, carried it a few hundred meters inland, rebuilt it. And then maybe next year the erosion came again, so the river again came closer, so they again shifted a few hundred meters inland. So this pattern of very short distance moves that

Inside The ETH Longitudinal Study

Jan Freihardt 10:56

happened repeatedly over the years.

Giannis Mavris 10:58

The researchers found two reasons for this behavior. Either people simply lacked the means for relocating, given that they had lost everything during natural disaster, or, and this was the vast majority of those staying, they simply didn't want to move away from their communities, families, or what was left of their land.

Jan Freihardt 11:15

The takeaways that I now draw from that Bangladesh study is very clearly there is an influence of environmental changes on migration, that in the villages that have erosion, more people migrate out of the village. But then basically all of them remain within Bangladesh. So we also have some people who left the villages abroad, but this is classical labor migration. So they go to Qatar or to Saudi Arabia for a job purpose, and this is also, I think, can be explained why this is rarely happening, that it's really the erosion that leads to international migration, because as mentioned, erosion usually takes a lot of the resources and the wealth of people. So it already comes at a cost to even get the work permit, the passport, the flight tickets, etc., to go to Saudi Arabia. And I think this also extrapolates to many other world regions, like many studies in other countries that I've read, they find very similar things that those affected by climate change, they usually move very short distance. And so I think this narrative of climate change will lead to massive international migration flows and millions of people will move into Europe or into North America due to climate change. I think this is right now not supported by what the literature finds. I think if that migration happens, then it's primarily due to economic inequalities. So if we are somehow concerned about these huge international migration flows, then I think it's uh it's also important to look at these global inequalities and where they come from and not to focus solely on climate change.

Jo Fahy 12:54

And Yanis, are the authorities in Bangladesh doing anything to help these people?

Giannis Mavris 12:59

Yes, uh actually they have started to build embankments and to reinforce some of the riverbanks. However, it seems that some villages are getting the support while others do not. And this is what Freihart wants to look at in a follow-up project on the justice implications of climate adaptations.

Jo Fahy 13:17

Okay, interesting. So we might hear more from Freihart's research in the future. But now we're going to the south of Bangladesh, to the Sundarbans, an area in the Ganges Delta, which features the largest mangrove forests in the world. And Yanis, you told me that the climate-related problems here are a bit different from the ones we just heard about happening in the north of the country.

Giannis Mavris 13:37

Yes, exactly. I got to speak to Gina Hosin, who's from Bangladesh herself and works as a research fellow at the University of Zurich. And she's conducting several studies in the St. Urbans.

Jinat Hossain 14:19

So it's difficult for the people to be there when there is a cyclone or flood and they have to relocate or

Climate Signals Vs Monsoon Baseline

Jinat Hossain 14:25

they are forced to relocate in some cases. But also sometimes they volunteer to live on those places and survive within these uh catastrophic causes.

Giannis Mavris 14:37

So people in the south face similar environmental problems to the ones people face up north. The problem specific to the south, though, is salinity.

Jinat Hossain 14:45

There are sea level rise, and then in the 1980s, around that time, people started aqua farming, prominently shrimp aquaculture, independently, but then it was supported by government and uh donors and NGOs because they thought they should use the saline water for bigger purpose, commercial purpose, like commercial shrimp aquaculture, and now it is spread a lot in the last few decades. And that made even the situation worse because the salt is everywhere. Uh, people cannot grow now the rice. People don't have agriculture anymore, so they have to go for other alternative livelihood options. So they uh migrate to the nearby cities or nearby uh districts for doing some other works like day labor or rickshaw pulling or working in the brick factory, which is very popular. Many migrate to Dhaka for the textile industry because you might know that uh we host uh the second largest textile industries in the world, and there's a huge option for the women to work there. Also, it's possible that they migrate abroad in the Middle East as labor, because that's also a big uh source of our national economy. Uh, this immigration and labor migration in the Middle East. Climate is one of the factors because most of the cases people lose their household, their belongings uh in cyclone or longer flood or waterlogging. But also, there are many other factors actually triggered them to make the decision of uh leaving their home and go for some other places.

Giannis Mavris 16:19

And uh can you tell us, is there some kind of uh government help for people that uh want to or have to dislocate or to even migrate within the country?

Jinat Hossain 16:29

So for the government we have cyclone center, most of the digester-prone area. So you can temporarily go and have shelter there. Uh, but the area where I work in Shatkira and Kulna, that region, I didn't find any permanent solution for this relocation. So there are uh projects called Astrayon uh projects that's like you give um uh household to the poor people, not only the climate migrants, but in general poor people. And that's everywhere uh nationwide. So that's not something specifically for the climate displaced or climate migrant people. But apart from that, what I observed during my uh field study that people actually rely on their social network mostly to take shelter when the cyclone center is not accessible, or maybe it's longer term and you cannot just stay in the

The Surprise: Short-Haul Migration

Jinat Hossain 17:23

cyclone center for for like years. So they try to get help from their social network, and that really helped them to um start again, like restart their life. And that is very inspiring that we see that where um the government or the adaptation governance sometimes is not so supportive, or I would say weak for the marginal community, uh, then how this marginal community or this vulnerable community really find a way with their social network to move forward, and I think super inspiring for the other countries who are struggling with the same reason.

Giannis Mavris 18:01

I asked Jinat how she sees Bangladesh's role as a pioneer. Could solutions here work for other regions too?

Jinat Hossain 18:07

In terms of governance, yes, we have good projects and good initiatives, and those can be, of course, example for the other parts of the world. But I would say, as a researcher, I'm also critical about some of the initiatives that the government has taken because there is a lot of um tendency of using climate change as a fundraising mechanism for the government and NGOs. And I think some benefits go to the people who are victims, but uh some also we heard that being corrupted or um used for other purposes. And the projects they are taking often in my analysis, it uh I found that they are promoting new liberal mechanisms. For example, I give example of the shrimp aquaculture, which has been taken as climate change adaptation measures by the government and by donors and NGOs, but now we see that that has a huge trade-off, uh, social ecological trade-off. One is the soil quality is degrading because you cannot produce any rice or vegetables anymore. On the other hand, there's a huge social impact because people are unemployed, they lose their farms, they lose their ponds and domestic animals, and they have to migrate, or they have to find some alternative livelihood options, especially for the women who are living on farmlands. So that's a huge gender and class impact, and that actually changed the whole situation in that area because there are a lot of external people coming to do shrimp aquaculture, having the shrimp factory, and they are high class, and then the people who cannot farm, they have to give over their land and they become poorer and they become the labor of these high-class people. So the even the class structure is shifting. I think that has a big social uh consequence in the society that we need to consider also when we design climate migration program.

Jo Fahy 19:58

The topic is really complex, isn't it? Some climate adaptation projects like the shrimp farms might seem like a good idea at first, but then there are negative social and perhaps also environmental consequences that have to be taken into account as well.

Giannis Mavris 20:12

Yes, and not only that, it also reinforces gender inequality.

Jinat Hossain 20:16

For example, when the men migrate, either seasonally or permanently, he left the families, and the family now start leading by the women, and the women has to find some job option or livelihood option because their option of household agriculture is now gone. So they have to go out, either work in the shrimp factory or catching, fetching some uh shrimp baby shrimp to sell in the market, and the market is exploitative for the women, and if they work as a daily, they are getting less payment than the male. So all these exploitation actually even getting higher when women are in the in the market and in the public sphere. On the other hand, when men go to other places, often they disappear or they have uh another wife there, and then more single-headed or female-headed households are appearing, and these women are leading the whole household alone, and there are more vulnerabilities.

Jo Fahy 21:28

Do recent cutbacks on money for development aid, I'm thinking from US aid, for example, that's been a very big topic that's been going on in the past few months, do these cutbacks have an impact on the situation in Bangladesh?

Giannis Mavris 21:42

Yes, not just the US aid cuts, but many others as well, especially from Western countries. Switzerland, for example, has been engaged in Bangladesh for five decades, and tackling the negative effects of climate change has been a key pillar of its bilateral support. But now Switzerland's international development Cooperation has fallen victim to the country's austerity measures. Around 430

Policy, Embankments, And Justice

Giannis Mavris 22:05

million Swiss francs have been cut from the budget for the next few years. And as a consequence, the Swiss Agency for Development and Cooperation will phase out its bilateral development programs in Bangladesh by the end of 2028. So that's a lot of money and that will be missing in some places.

Jo Fahy 22:24

Absolutely. We're going to have to see how things develop in the future. So thank you, Yanis, for this very interesting story and also for joining us on the Swiss Connection Podcast for the first time.

Giannis Mavris 22:33

You're welcome. Thanks a lot.

Jo Fahy 22:36

In the next episode of the Swiss Connection Science Podcast, we'll find out why Switzerland is so keen to get into the business of semiconductors. They're an essential but difficult to produce piece of tech. Hit subscribe now in your podcast feed to make sure you don't miss out. For more science stories, you can visit our website swisinfo.ch, and you can help others to find our podcast by leaving us a five-star review or sharing our podcast with a friend. Today's episode was recorded and edited by our science and video Michele Andina journalist For more content, check out our website swisinfo.ch. I'm Jo Fahy. Thanks for listening.