Climate change poses risks to agriculture and food security through changing weather patterns and more frequent climate extremes. If not effectively managed, these risks could place increasing pressure on agricultural production.
For ASEAN Member States (AMS), lower or less reliable production in major agricultural areas could affect domestic food availability, rural livelihoods and food-price stability. When multiple production areas are impacted simultaneously, there could also be wider implications for regional food supply.
Understanding how these changes could affect agricultural production across Southeast Asia can support early adaptation and strengthen the resilience of regional food systems. Given the interconnected nature of ASEAN’s food systems, building agricultural resilience across the region can contribute to collective food security.
About ASEAN Agri Climate Impact Twenty (AACIT) Study
To examine how climate change could affect agriculture across ASEAN, the AACIT study was jointly undertaken by the Singapore Food Agency (SFA) and the Tropical Marine Science Institute (TMSI) of the National University of Singapore (NUS). The study will be presented for adoption by ASEAN Ministers at the upcoming 48th ASEAN Ministers on Agriculture and Forestry (AMAF) Meeting.
AACIT was designed to identify crops and geographical areas that may be more vulnerable to climate-related risks. It examined how future climate change may affect five major crops under the ASEAN Food Security Information System (AFSIS) – rice, maize, cassava, sugarcane and soybean – across Southeast Asia from 2025 to 2044, compared with the historical period of 1995 to 2014.
Using climate information from Singapore’s Third National Climate Change Study together with crop modelling, AACIT assessed how changes in temperature and rainfall, climate extremes such as heavy rainfall, drought and heat stress, and climate variability like El Niño could affect the production of these crops across Southeast Asia.
Key findings of AACIT
1. Climate impacts are expected to vary across the region
Southeast Asia is projected to become warmer, with more frequent and longer heatwaves. Rainfall patterns are expected to vary across locations and over time. Some areas may experience heavier rainfall and flooding, while others may face prolonged dry spells or greater drought stress. These changes could affect water availability, planting schedules and crop production.
Climate change will therefore not affect all parts of ASEAN in the same way. Adaptation measures will need to consider local conditions, crop types and their planting seasons.
2. Climate change could affect crop production differently, with variations across crops, years and locations
At the regional level, the study projects the following average changes in crop production across five crop types from 2025 to 2044:
| Crop | Average changes in crop production | Variability across favourable and unfavourable years1 |
| Rice | 3% to 5% decline | 4% increase in favourable years, 15% decline in unfavourable years |
| Maize | 5% to 6% decline | 2% decline in favourable years, 19% decline in unfavourable years |
| Cassava | 16% increase | 32% increase in favourable years, 2% increase in unfavourable years |
| Sugarcane | 1% to 4% decline | 1% increase in favourable years, 15% decline in unfavourable years |
| Soybean | 11% to 13% increase | 30% increase in favourable years, 5% decline in unfavourable years |
1Favourable and unfavourable years refer to the future years with the highest and lowest projected annual yields, respectively.
More favourable average projections for some crops do not mean that they are free from climate-related risks. Production could still be affected by variability in climate conditions in any particular year including extreme heat, heavy rainfall or drought in an unfavourable year. In addition, these regional averages do not apply equally across countries, production systems or growing seasons. Crop responses can also vary depending on soil conditions, water availability and crop management practices. All these should be considered alongside variations across favourable and unfavourable years, and some areas may also experience larger impacts than indicated by regional averages.
3. Strong El Niño events can add pressure to crop production
The study’s simulations suggest that very strong El Niño events, which often bring hotter and drier conditions to parts of Southeast Asia, can reduce regional average crop production by up to about 10%.
The extent of these impacts varies across crops, seasons, production systems and locations. For example, the study indicates that El Niño conditions generally have a greater impact on rice than on the other crops assessed. Rainfed production systems are also generally more sensitive due to their greater dependence on seasonal rainfall. This highlights the importance of preparing for year-to-year climate variability, while also planning for long-term climate change.
Why AACIT matters for ASEAN’s regional food resilience
AACIT provides science-based insights to help AMS better understand where climate-related risks to agricultural production may emerge. While the findings should not be interpreted as precise forecasts of future crop production or food supply, such early indications can support risk-informed food-security planning, source diversification and better preparedness for potential supply impact.
Potential applications include adjusting planting calendars, adopting more climate-resilient crop varieties and farming practices, improving irrigation efficiency and water management, as well as strengthening climate monitoring, seasonal forecasting and early-warning systems. Considered alongside local knowledge and national priorities, the findings can also inform agricultural planning, evidence-based policy-making, and regional dialogue on food security and climate adaptation.
