TN paddy farmers unlearn traditional practices as climate change takes a toll

Climate change spares none, as the paddy cultivators of Tamil Nadu are quickly discovering.

Changing rainfall patterns and rising temperatures have been vastly impacting crop yields in the state, paddy cultivation taking the biggest hit. And, farmers in the fertile Cauvery basin are bearing Nature’s wrath like never before.

Around 49,08,941 hectares — or 37.7 per cent of the total land — in Tamil Nadu is used for cultivation. Of this, paddy is sown on nearly 45 per cent, or 22,17,269 hectares.

Cauvery districts

In the Cauvery basin, the 'Rice Bowl' which encompasses the districts of Thanjavur, Tiruvarur, Mayiladathurai, Nagapattinam, Cuddalore, Perambalur, Ariyalur and Karur, paddy is cultivated on 8,03,310 hectares, per government data.

Climate change, with the accompanying heavy rains and extreme weather events, has hit paddy cultivation in this region hard. Meanwhile, as demand remains steady, farmers from other districts are also increasingly sowing paddy.

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About 2,18,722 hectares of paddy is sown in Thanjavur, followed by 2,05,795 hectares in Tiruvarur. Non-Delta districts such as Tiruvannamalai cultivate paddy on 1,84,422 hectares. In Cuddalore, paddy accounts for 1,42,741 hectares and in Ramanathapuram, about 1,36,340 hectares.

Structural change

Supriya Sahu, Additional Chief Secretary for Environment, Climate Change and Forests Department, Government of Tamil Nadu, said the state has undergone a structural economic shift over the years.

Agriculture’s share in the Gross State Domestic Product (GSDP) has fallen to 9.93 per cent in 2023-24 from 12.11 per cent in 2011-12, reflecting a broader global trend where industrialisation and services drive economic growth.

Besides rapid urbanisation and the growth of the automobile, textiles and IT sectors, which have led to the diversification of economic activity, water stress and climate variability have made farming more unpredictable. In spite of it all, agriculture remains vital, supporting nearly 40 per cent of the state’s workforce.

"Certain districts like Coimbatore, Dharmapuri, and Kanchipuram have seen groundwater depletion while erratic monsoons and rising temperatures (+0.68°C per century) have impacted crop productivity. Finally, farmers are shifting towards high-value crops such as horticulture, oilseeds and sugarcane, which offer better income potential but contribute differently to GSDP," Sahu told The Federal.

Embracing other crops

Given unpredictable weather patterns, the popularity of cereals, pulses and other cash crops has surged.

About 31,71,953 hectares of land in Tamil Nadu is used for cereals cultivation, 39,74,053 hectares for pulses, 8,89,571 for oil seeds and 3,50,617 hectares for other cash crops.

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Rengalakshmi Raj, Development Researcher at the MS Swaminathan Research Foundation, told The Federal: "Rising maximum temperature is affecting grain development while a drop in minimum temperature affects sterility. Farmers in non-Delta districts like Villupuram and Tiruvannamalai choose to grow paddy because of heavy rainfall.

“Given the dependency of the Cauvery basin on the release of water from Karnataka, the farmers are choosing other crops that don't need as much irrigation," she added.

Crop yields hit

Tamil Nadu overall produces 79,06,373 tonnes of paddy, of which about 34 per cent is grown in the Delta districts, amounting to 29,20,793 tonnes.

However, the overall paddy productivity has seen fluctuations over two decades. From 3,196 kg per hectare in 2001-02, it dropped to 3,039 kg in 2010-11, and rose to 3,566 kg per in 2021-22.

Changing weather patterns are affecting the crop yield, said Rengalakshmi. Although the overall production might seem to be increasing, a decline in productivity is expected in the future.

Monsoon patterns

In the past few years, the northeast monsoon has extended till January, which is the harvest season. Rainfall during harvest damages the crop.

Sowing requires plenty of irrigation. If the farmers in the Cauvery delta do not get rains in June from the southwest monsoon, and if Cauvery water from Karnataka gets delayed, the yield will be poor. Or, they have to delay sowing. Many farmers gradually move to non-agricultural occupations because of poor yields.

The latest Climate Risk Assessment and Adaptation Plan of Tamil Nadu used the Decision Support System for Agro-technology Transfer (DSSAT) to project significant yield reductions for major crops under future climate conditions. These crops include rice, maize, sorghum, groundnut and black gram across various agro-climatic zones.

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Risk assessment

Among the Cauvery delta districts, Thanjavur, Nagapattinam and Tiruvarur are frequently impacted by flooding and soil salinity, affecting paddy cultivation. Ramanathapuram and Thoothukudi struggle with prolonged dry spells, limiting water availability. Dharmapuri and Krishnagiri experience heat stress, impacting maize and pulses.

Further, a climate risk assessment incorporating hazards such as floods and droughts as well as vulnerability including water availability, biophysical factors and socio-economic factors was done.

This revealed that agriculture in the districts of Ranipet, Ariyalur, Perambalur, Chengalpattu, Ramanathapuram, Dharmapuri, Kancheepuram, Cuddalore, Krishnagiri, Vellore, Thiruvannamalai, Sivagangai, Madurai and Virudhunagar showed very high agriculture risks.

Villupuram, Thiruvarur, Nagapattinam and Theni would be at high risk in agriculture due to climate change whereas Erode and Coimbatore indicate very low agriculture risk.

Dry season, intense rains

"The effects vary across crops and regions. Paddy yields in the Cauvery Delta are impacted by delayed monsoons and water stress, leading farmers to adopt short-duration and drought-resistant varieties. Maize and pulses in western Tamil Nadu are affected by heat stress while sugarcane cultivation has improved due to better irrigation access,” said Additional Chief SecretarySahu.

“Tamil Nadu’s State Climate Change Cell, in collaboration with TNAU and IMD, has conducted extensive assessments that revealed an increase in extreme hot days, affecting flowering and grain formation in crops. Shifts in monsoon patterns, impacting irrigation and crop cycles and a decline in paddy and maize productivity, particularly in vulnerable districts," she added.

The Economic Survey 2024-25 highlighted clear trends — average temperatures have risen by +0.68°C per century, and rainfall patterns have become increasingly unpredictable.

Tamil Nadu, which receives an average annual rainfall of 925 mm, now sees years of prolonged dry spells followed by intense downpours, leading to flooding, soil erosion and water scarcity.

Heat waves

A former director of the Regional Meteorological Centre, S Balachandran, said the rainfall pattern has changed and heat waves are increasing in the state.

Climate change has led to short-interval intense rainfall spells. This has become a pattern over 10-15 years. Though maximum temperatures of above 30 degree Celsius have been recorded a few decades ago, heat waves have become more common in recent years, he added.

Over the past four years, the Cauvery delta has experienced heavy rainfall from mid-December to mid-January, forcing paddy farmers to change their farming practices.

According to AP Ravindran from the Farmers Federation, "Climate change has resulted in heavy rainfall over short durations, affecting crops."

Suggested steps

Although Tamil Nadu receives sufficient rainfall during the southwest monsoon, which covers the sowing stage (June to September), the northeast monsoon during October to December brings sudden heavy spells that are short-lived.

This extreme weather pattern is a result of climate change. Ravindran emphasised the need for increased reservoir storage capacity, more water tanks and strengthened bunds to manage water effectively.

"For vegetables, heavy rainfall during the flowering stage damages the crop since flowers fall off due to heavy rains. Mist can also damage the crops due to excessive moisture retention in vegetables. Climate change is changing the ratio of sunlight and excessive rains, which reduces yield," Govindhara, a farmer from Kallakurichi, told The Federal.

Shifting sowing patterns

Farmers in various parts of the state have shifted sowing from September to October and advanced the harvest from January to mid-December to protect their yield from heavy rainfall.

The shift in seasons has led to farmers adapting to new farming patterns.

Weather blogger K Srikanth believes this is the right way forward. There is a need to unlearn and relearn agricultural practices as a delay in the withdrawal of the southwest monsoon or extended northeast monsoon can impact the crops, he said.

The postponement of sowing can be helpful, as harvesting can then be done in February. This avoids harvesting in January, which is seeing extended heavy rainfall in recent times. Particularly for the Delta districts, the sowing of crops that is done usually in June should also be postponed so that the irrigation can be done after the Mettur dam is full, say experts.

Experts also suggest embracing new farming methods and opting for climate-resilient crops such as millets, coconut and resilient variety of cereals and paddy to overcome the challenges posed by climate change.

No easy solution

According to R Rajkumar, principal scientist at the MS Swaminathan Research Foundation, new smart methods of irrigation need to be adopted such as the System of Rice Intensification (SRI) that focuses on managing plants, single seedling planting, improving soil conditions and reducing plant density to ensure productivity.

“The system of Atmospheric Water Generator (AWG) method of irrigation to provide adequate water in case of extreme heat can be helpful," he told The Federal. But he warned there were no immediate solutions to climate change.

“These methods need to be communicated to the farmers to prevent losses. We also have a system of plant clinics to provide a plan of choosing the right crop and cultivation techniques for farmers to prevent yield loss. More such dedicated centres can inform and educate the farmers," he said.

Climate-resilient crops

With the Tamil Nadu State Action Plan on Climate Change (TNSAPCC) 2.0 nearing final approval, the state is investing in climate-resilient crops, carbon-smart agriculture, and post-harvest innovations.

By integrating technology, policy and financial support, the state is ensuring that farmers don’t just survive climate change but thrive in a more sustainable future.

"The focus is on climate-smart agriculture, water conservation, and technology integration. Tamil Nadu is expanding micro-irrigation, promoting AI-based weather forecasting and strengthening post-harvest infrastructure to enhance sustainability and improve farm incomes,” said Sahu.

For better earnings

“While erratic weather, rising temperatures and water stress have made traditional farming more challenging, farmers are increasingly integrating dairy, poultry, fisheries and agro-processing into their livelihoods," she said.

She added that beyond weather forecasts, satellite-based remote sensing and AI-driven soil mapping were optimizing nutrient management and water use. Precision farming tools like drones and automated irrigation systems enhance yields.

AI is also revolutionizing post-harvest operations — predictive analytics on market trends help farmers sell at optimal prices, and AI-integrated cold storage minimizes food loss.

Weather stations

Tamil Nadu is scaling up automated weather stations, AI-powered crop insurance and digital farming platforms, ensuring a technology-driven, climate-resilient agricultural landscape, Sahu added.

Meanwhile, TNSAPCC 2.0 has successfully progressed through a rigorous national review process and is now in its final stage of approval.