El Nino is a weather phenomenon that occurs when ocean temperatures in the central and eastern Pacific Ocean rise above normal. The warming causes changes in atmospheric patterns, leading to a weakening of the southeast trade winds that flow to the intertropical convergence zone over India. These winds are the main driving force of the Indian summer monsoon, so El Nino events are associated with weak monsoons and lower than average rainfall over the subcontinent.
El Nino affects the monsoon by disrupting the normal circulation of air and moisture over the Indian Ocean and the Arabian Sea. This reduces the amount of moisture-laden clouds that reach India and causes dry spells or droughts in some regions. El Nino also influences the formation and movement of low-pressure systems and cyclones that bring rain to India during the monsoon season.
El Nino events are categorised according to the magnitude of temperature rise above normal, as weak, medium or strong. Weather models are suggesting 2023 El Nino could be strong, which could have a negative impact on the monsoon rainfall. However, there are other factors that also influence the monsoon, such as the Indian Ocean Dipole, which is a similar phenomenon in the Indian Ocean. A positive Indian Ocean Dipole tends to enhance the monsoon rains, while a negative one tends to suppress them. The IMD has predicted the development of a positive Indian Ocean Dipole over the Indian Ocean during monsoon 2023, which could offset some of the adverse effects of El Nino.
How often does El Nino occur?
El Nino occurs every two to seven years on average. However, El Nino is not a regular cycle, or predictable in the sense that ocean tides are. El Nino events vary in intensity, duration and frequency. The last El Nino event occurred in 2019-2020 and was a weak one. The current El Nino event started in late 2022 and is expected to last until mid-2023. It could be a strong one according to some weather models.
How can we cope with El Nino induced droughts?
El Nino-induced droughts can have severe impacts on agriculture, food security, health, and livelihoods of millions of people, especially in developing countries. Coping with El Nino-induced droughts requires preparedness, partnership, and resilience. Some of the strategies that can help cope with El Nino-induced droughts are:
Improving access to and use of climate information and forecasts. This can help farmers and other stakeholders plan ahead, adjust their cropping patterns and practices, adopt drought-tolerant crops and varieties, and reduce their exposure to risks.
Strengthening social protection systems. This can help cushion the effects of drought on the most vulnerable groups, such as children, women, elderly, and poor households. Social protection can provide cash transfers, food assistance, school feeding, health insurance, and other forms of support to help people meet their basic needs and cope with shocks.
Enhancing water management and conservation. This can help reduce water stress and improve water availability for domestic, agricultural, and environmental purposes. Water management can include rainwater harvesting, irrigation efficiency, groundwater recharge, watershed management, and water allocation.
Promoting sustainable land management and agroecology. This can help improve soil health, fertility, and water retention, reduce erosion and degradation, enhance crop diversity and productivity, and sequester carbon. Sustainable land management and agroecology can include practices such as mulching, intercropping, agroforestry, organic farming, and conservation agriculture.
Building capacity and awareness. This can help empower communities and stakeholders to understand the causes and consequences of El Nino-induced droughts, access relevant information and resources, participate in decision-making processes, and adopt appropriate coping strategies.
Fostering coordination and collaboration. This can help mobilize resources, share knowledge and experiences, leverage synergies and complementarities, and enhance effectiveness and efficiency of interventions. Coordination and collaboration can involve different levels of governance, sectors, disciplines, actors, and regions.
Which countries are most affected by El Nino induced draught?
El Nino-induced droughts can affect different countries and regions in different ways, depending on their geographic location, climate variability, and vulnerability¹. However, some of the countries that are most affected by El Nino-induced droughts are:
Ethiopia. Ethiopia is experiencing its worst drought in decades due to El Nino. The drought has decimated food crops and led to poor harvests. Some 8.2 million Ethiopians – out of a population of nearly 100 million – need food aid.
Papua New Guinea. Papua New Guinea has been hit hard by poor harvests caused by lower than average rainfall linked to El Nino. The drought has affected the food security and livelihoods of millions of people, especially in rural areas.
Central America. Central America, particularly Guatemala, El Salvador, Honduras and Nicaragua, have recorded below average rainfall this year due to El Nino. This has resulted in widespread damage to crops and rising food prices, affecting an estimated 2.3 million people who need food assistance.
Indonesia. Indonesia has suffered from a prolonged dry season exacerbated by El Nino, which led to forest fires smouldering across the archipelago in October and November. The fires caused severe air pollution, health problems, and environmental damage.
Southern Africa. Southern Africa, including Angola, Botswana, Lesotho, Malawi, Madagascar, Mozambique, Namibia, South Africa, Swaziland, Zambia and Zimbabwe, have experienced an extended period of reduced rainfall due to El Nino. This has resulted in water shortages, crop failures, livestock deaths, and increased hunger and malnutrition.
What are some examples of successful coping strategies?
Some examples of successful coping strategies for El Nino-induced droughts are:
Using climate information and forecasts to plan ahead. For example, farmers in Indonesia have used seasonal climate forecasts to adjust their planting dates, crop varieties, and fertilizer use to cope with El Nino-induced droughts. This has helped them reduce crop losses and increase yields.
Implementing social protection programmes to support the most vulnerable. For example, UNAIDS and its partners have supported countries in eastern and southern Africa to provide cash transfers, food assistance, school feeding, health insurance, and other forms of support to people living with and affected by HIV who are also facing El Nino-induced droughts¹. This has helped them meet their basic needs and cope with shocks.
Promoting sustainable land management and agroecology to improve soil health and water retention. For example, farmers in Papua New Guinea have adopted practices such as mulching, intercropping, agroforestry, organic farming, and conservation agriculture to cope with El Nino-induced droughts. This has helped them improve soil health, fertility, and water retention, reduce erosion and degradation, enhance crop diversity and productivity, and sequester carbon.
Building capacity and awareness among communities and stakeholders. For example, UNAIDS and its partners have conducted workshops and trainings for communities and stakeholders in eastern and southern Africa to enhance their understanding of the causes and consequences of El Nino-induced droughts, access relevant information and resources, participate in decision-making processes, and adopt appropriate coping strategies. This has helped them empower themselves and take action to mitigate the impacts of El Nino-induced droughts.
Fostering coordination and collaboration among different levels of governance, sectors, disciplines, actors, and regions. For example, UNAIDS and its partners have facilitated coordination and collaboration among different levels of governance, sectors, disciplines, actors, and regions in eastern and southern Africa to mobilize resources, share knowledge and experiences, leverage synergies and complementarities, and enhance effectiveness and efficiency of interventions to cope with El Nino-induced droughts. This has helped them create a more coherent and comprehensive response to El Nino-induced droughts.
What are some benefits of El Nino?
El Nino is not all bad. It can also have some benefits for certain regions and sectors, depending on the location, timing, and intensity of the phenomenon. Some of the benefits of El Nino are:
Milder winters in some parts of North America. El Nino usually brings warm, dry weather to southern Canada and northern continental United States, which can reduce heating costs, snow removal expenses, and winter-related accidents and illnesses.
Reduced hurricane activity in the Atlantic Ocean. El Nino tends to suppress the formation and intensification of hurricanes in the Atlantic Ocean by creating unfavorable wind shear and atmospheric stability conditions. This can lower the risk of coastal damage, flooding, and casualties from hurricanes.
Increased rainfall in some parts of South America. El Nino usually brings more rain to the west coast of South America, especially Peru and Ecuador, which can relieve droughts, replenish water resources, and boost crop production. However, too much rain can also cause floods and landslides in these regions.
Improved air quality in Southeast Asia. El Nino can reduce the occurrence and severity of forest fires in Indonesia and other parts of Southeast Asia by increasing rainfall and humidity. This can improve air quality, reduce health problems, and protect biodiversity from fire damage.
Increased fish catch in some parts of the Pacific Ocean. El Nino can create favorable conditions for some fish species to thrive in some parts of the Pacific Ocean by altering ocean currents, temperatures, and nutrient availability. For example, El Nino can increase the abundance of tuna and swordfish in the eastern Pacific Ocean near South America.