Bangladesh faces one of the worst climate change situations putting lives of millions of people, mostly in the coastal belt areas, at great risk of forced migration.

A steady seawater intrusion is threatening agriculture and food security in a roughly 700 km stretch of coastal areas of Bangladesh. Farmers, however, are preparing adaptation strategies to survive instead of leaving their ancestral homes.

Hundreds and thousands of families directly dependent on agriculture in coastal land near the Bay of Bengal face less crop production every year due to increasing salinity, studies show.

The coastal and offshore areas of this low-lying, densely populated country are increasingly becoming vulnerable to the steadily changing climate. Given this delegations from Bangladesh repeatedly demanded more allocation for climate change adaptation plans at various international forums including at the UN climate change conferences.

In a recent study, experts observed that saline water intrusion due to the reduction of freshwater flow from upstream, salinization of groundwater and fluctuation of soil salinity are major concerns and can seriously affect the country’s food production.

According to a recent study, about one million hectares, or around 70 per cent of arable lands in the southern coastal areas of Bangladesh, are affected by various degrees of soil salinity.

The study predicts that if the current trend of climate change continues, rice production could fall by 15 per cent and wheat by 35 per cent.

Bangladesh Agriculture Research Institute or BARI scientists monitoring such changes said that by the turn of this century, a major portion of the coastal areas would be lost to such saline water intrusion sending a large population to seek alternative sources of income.

“We have noticed fewer harvests of crops in the recent past in Borguna, Bhola and parts of Noakhali estuaries,” said one of the lead scientists of BARI.

He explained that temperature plays a major role in salinity in the coastal regions. If the temperature rises, the soil loses moisture and the salt from tidal or storm surges becomes concentrated, which results in crops wilting or dying – a phenomenon that is already visible.

Salinity in Bangladesh, one of the countries worst affected by decades of sea level rise, causes an unfavourable environment that restricts normal crop production throughout the year.

The freshly deposited sediment from upstream in the coastal areas of Bangladesh becomes saline as it comes in contact with the seawater and continues to be inundated during high tides and ingress of seawater through creeks.

A study found that the affected area increased from 8,330 square km in 1973 to 10,560 square km in 2009,  according to the Soil Resource Development Institute  in 2010.

Another study - Digital Evaluation Model (DEM) predicts the salinity induced by storm gushes in the coastal regions. The study compared projections for future storm surges at current and predicted sea levels.

It shows that potential storm gushes circumstances from 1 to 9 meters can impact up to 33 per cent of the southern regions. The occurrence of cyclone-related storms will increase and make cultivation and settlement in the region more difficult. The predicted sea-level rises and saltwater contamination will intensify the adverse effects of salinity.

The challenge now is to confront the rising seawater intrusion. Experts say that despite attempts to increase resilience, climate challenges continue to result in large economic crises, retarding economic growth and slowing progress in reducing poverty.

The saline water intrusion is now an alarming situation as non-coastal areas in many regions are also affected by salinity.

Many studies testify to the above. One of them is a study from 1973 to 2009 by the Soil Resources Development Institute or SRDI.

Their report said that the total amount of saline-affected land in Bangladesh was 83.3 million hectares in 1973, which had increased up to 102 million hectares in 2000 and the amount has risen to 105.6 million hectares in 2009 and continues to increase, according to SRDI.

In the last 35 years, salinity increased by around 26 per cent in the country, spreading into non- coastal areas as well.

The economic cost of climate change in Bangladesh is colossal as predicted by the World Bank. They reported that the cost of climate change is very high. A World Bank report released in 2022 shows;

-  Average tropical cyclones cost Bangladesh about $1 billion annually.-  By 2050, one-third of agricultural GDP may be lost due to climate variability and extreme events – a devastating figure as the agriculture sector represents around half of employment in the country.-  13.3 million people may become internal migrants in the next 30 years due to climate impacts on agriculture, water scarcity, and rising sea levels, with higher impacts on women.-  In case of severe flooding, GDP could fall by as much as 9 per cent.-  The costs of environmental degradation and natural disasters are predicted to rise over time, compounded by higher heat, humidity, and health impacts.

Given this report, the WB research said that Bangladesh will need at least $12.5 billion, approximately 3 per cent of GDP in the medium term for climate action. 

The financing gap can partially be covered through additional funds from budget prioritization, carbon taxation, external financing, and private investment. It will be critical to address immediate and urgent challenges for climate change and development.