The La Niña weather phenomenon, characterised by cooler-than-average sea surface temperatures in the central and eastern Pacific Ocean, has been anticipated to exert its influence on weather patterns worldwide since August 2024. El Niño and La Niña are opposite phases of the weather phenomenon known as the El Niño-Southern Oscillation (ENSO). When La Niña occurs, the weather effects are opposite to those of El Niño. Areas that experienced drought and heat during El Niño often see a shift to wetter conditions during La Niña. Conversely, regions that faced abnormal amounts of rainfall during El Niño may turn dry and experience drought-like conditions during La Niña.
La Niña typically brings wetter-than-average conditions to the Pacific Northwest and northern United States, while the southern United States may face drier and warmer weather. In South America, La Niña often results in above-average rainfall in northern regions, contrasting with drier conditions in southern areas. Across the Asia-Pacific and Africa regions, impacts vary, with increased rainfall expected in parts of Southeast Asia and Australia, while other areas may experience reduced precipitation. Its impacts extend beyond weather phenomena and affects various socioeconomic sectors, including agriculture, water management, energy demand, and commodity markets.
In ASEAN+3, each country is impacted by La Niña. For example, La Niña brings increased rainfall to most parts of Thailand and slightly lower temperatures across the country. Besides Thailand, Indonesia, the Philippines, and Viet Nam also typically experience heightened rainfall during La Niña. This increased rainfall can benefit agriculture by replenishing water reservoirs and improving soil moisture. However, excessive rainfall can lead to flooding, landslides, and waterlogging, causing significant damage to crops, infrastructure, and livelihoods. In other countries such as China, Japan, and the Republic of Korea, La Niña's influence can result in varied weather patterns. The increased rainfall during La Niña can be advantageous for rice cultivation by ensuring sufficient water supply, but it also heightens the risks of flooding and waterlogging in some areas. Conversely, colder temperatures and reduced precipitation during La Niña events can adversely affect winter wheat and other crops that rely on adequate moisture and moderate temperatures during their growing seasons. Moreover, increased snowfall in specific regions can disrupt agricultural planning, practices, strategies, and crop outcomes. Consequently, farmers in these regions often face challenges in balancing water availability with crop requirements.
To mitigate La Niña's impact on agriculture and enhancing resilience against its weather variability, effective water management, diversified crop practices, and improved forecasting are crucial. Investments in irrigation infrastructure, water storage facilities, and drainage systems can help regulate water supply and reduce the risk of water-related disasters. Diversifying crop production can enhance resilience to La Niña-induced weather variability. Farmers can explore drought-resistant crop varieties, shift planting schedules, and adopt agroforestry and intercropping practices to improve soil health and water retention. In addition, strengthening early warning systems and weather forecasting capabilities is essential for enabling farmers and policymakers to anticipate La Niña's onset and prepare accordingly.
As La Niña takes hold in 2024, its impacts on global weather patterns underscore the interconnectedness of Earth's climate system. It emphasises the importance of preparedness and adaptation to natural variability. Monitoring and understanding these phenomena are essential for building resilience and mitigating risks in an ever-changing climate. Particularly in the ASEAN+3 region, investing in adaptive strategies, strengthening resilience, and fostering regional cooperation can empower the agricultural sector to mitigate risks, seize opportunities, and contribute to sustainable development goals amidst a changing climate landscape.
Bussapailyn Shimphalee*
18 July 2024
* This article is a product of the APTERR Secretariat. The views and opinions expressed in this article are those of the author and do not necessarily reflect the views of the APTERR Secretariat and its APTERR members.