Heat and Deluge Challenge Bangladesh’s Food Security

Bangladesh is grappling with a climate paradox: prolonged heatwaves and sudden deluges striking within the same cropping season. In April 2024, the country experienced its longest heatwave since 1948, lasting 30 consecutive days with temperatures exceeding 43°C in districts such as Chuadanga, Rajshahi, and Bogura. These extreme temperatures coincide with critical crop stages, including flowering and grain filling, severely reducing yields. During the 2024 Boro season, rice panicle sterility caused yield losses of nearly 20 percent in several districts, while mango orchards in Rajshahi reported up to 40 percent fruit drop. Vegetable growers in Jessore lost entire cucumber and tomato harvests due to flower abortion triggered by high day and night temperatures.

Irrigation, once a buffer against heat stress, has become increasingly unaffordable as diesel costs rise and groundwater levels decline. Farmers relying on diesel pumps face costs that can exceed 15–20 percent of total production expenses, forcing many to leave fields unirrigated.

Simultaneously, torrential rainfall strikes in sudden bursts, with over 200 mm falling in a single day in some areas, leaving soil waterlogged, seedlings destroyed, and fields submerged. In Sylhet’s haor regions, pre-monsoon floods in 2024 inundated more than 200,000 hectares of Boro rice, resulting in a national loss of nearly 1.1 million tonnes, enough to feed over 5 million people. In Khulna, saline intrusion after tidal surges compounded the damage, making replanting almost impossible. This combination of heat and deluge traps farmers in a relentless cycle of crop failure, income loss, and deepening vulnerability.

Field Realities & Farmer Struggles: Smallholder farmers, who comprise over 80 percent of Bangladesh’s agricultural workforce, are the most exposed to climate extremes. With landholdings averaging less than one hectare, they cannot diversify crops across plots. A single heatwave sterilizing rice or a flood washing away jute can erase an entire season’s income. Farmers often resort to borrowing from informal lenders at high interest rates exceeding 20 percent, selling livestock, or withdrawing children from school. Repeated crop failures have forced many to migrate to cities for daily wage labor, further weakening rural communities.

Women farmers face disproportionately higher risks. They are critical to transplanting, weeding, and post-harvest care, yet rising heat causes dehydration and heat exhaustion. Floods increase their workload as they juggle farm duties with caregiving in unsafe, waterlogged conditions. Lacking access to credit, extension services, and decision-making platforms, recovery is slow. Repeated shocks erode dignity, push households deeper into poverty, and disrupt food supplies when harvested produce spoils before reaching markets.

National Stakes: Agriculture contributes 13 percent to Bangladesh’s GDP and employs over 40 percent of the population, making it central to economic stability. A single crop failure can ripple nationwide. In 2024, flash floods destroyed over a million tonnes of rice, forcing emergency imports at higher global prices and pushing food inflation above 10 percent in urban centers. Vegetable and fruit prices, including brinjal, tomato, and green chili, doubled in Dhaka after rains cut off supply chains, compounding hardship for low-income consumers.

Heat stress alone carries macroeconomic risks. A 2023 World Bank study projected that rising temperatures could shrink GDP by nearly 6 percent by 2050 without adaptation. Losses from extreme weather, crop failures, livestock deaths, and damaged infrastructure already run into billions annually. This crisis is no longer a rural problem: it threatens food sovereignty, drives costly imports, and undermines national economic stability.

Climate Science: Bangladesh’s climate data signals a deepening crisis. Average temperatures have risen by 0.5°C over the last five decades, with heat extremes intensifying. In 2023, Chuadanga recorded 43°C, the highest in decades. Rainfall has shifted from steady monsoons to fewer but heavier downpours. In 2024, Chattogram recorded nearly 300 mm of rain in just 24 hours, triggering floods that devastated crops. These extremes reflect the global phenomenon of “compound events,” where simultaneous heatwaves and deluges become increasingly common in South Asia.

Science is stark. Rice, the staple providing two-thirds of Bangladesh’s calories, loses up to 10 percent yield for every 1°C rise during flowering. Flooding for over 10 days destroys even tolerant varieties, while heat fosters pest outbreaks like brown planthopper and stem borer. Livestock suffers as well: milk yield declines, poultry deaths increase, and waterborne cattle diseases spread rapidly. Groundwater depletion and erratic rainfall intensify these effects. Evidence and farmer experience confirm that climate change is already reshaping agriculture and threatening food security.

Policy Imperative: Addressing Bangladesh’s climate crisis demands more than ad hoc relief. Seeds remain the frontline defense. Heat-tolerant rice varieties such as BRRI dhan67 and flood-tolerant BRRI dhan51 and 52 must be produced and distributed on schedule, not weeks after disasters. Water management strategies, community ponds, rainwater harvesting, and solar irrigation can buffer both drought and deluge. Climate-informed cropping calendars, supported by SMS alerts or community radio, can guide farmers to stagger planting and reduce simultaneous crop failures.

Institutional innovation is equally urgent. A rapid crop-loss assessment unit using satellite imagery and local reporting could trigger faster response mechanisms. Index-based insurance linked to rainfall or heat thresholds should be scaled up, ensuring farmers receive timely payouts. Social protection programs can align with adaptation: cash-for-work initiatives could employ villagers to build raised embankments, dikes, and storage ponds. Investments in rural infrastructure, including elevated roads, cold storage, and flood-proof markets, will reduce post-harvest losses. Even redirecting 10–15 percent of current agricultural subsidies toward resilience (seed systems, irrigation, water management) can transform Bangladesh from reactive disaster relief to proactive food security.

Now or Never: The twin threats of extreme heat and unseasonal deluge are not merely episodic disasters; they define Bangladesh’s agricultural trajectory. Farmers are experimenting with short-duration rice, integrated cropping systems, and homestead aquaculture, yet these initiatives remain fragmented without institutional support. Adaptation is no longer optional; it is essential for sustaining food sovereignty. Inaction carries tangible costs: lost harvests, rising rice and vegetable imports, spiking food prices, and deepening rural poverty. Targeted investments in resilient crop varieties, affordable irrigation, rapid access to credit, and climate-proof rural infrastructure can transform vulnerability into resilience and secure the livelihoods of millions.

For a delta nation on the frontline of climate extremes, the choice is stark and immediate. Policymakers must implement integrated, farmer-centered strategies to safeguard the backbone of national food security. Generations of farmer ingenuity have shown remarkable resilience, but without decisive policy action, even these efforts may fail against intensifying heatwaves, floods, and saline intrusion. The window to act is narrow: delaying action risks eroding food security, destabilizing rural economies, and undermining decades of development. Immediate, coordinated policy response is imperative.


Dr. Shahrina Akhtar is 
National Consultant at 
ICCAP Project, APRACA.