NEWS & EVENTS

Expected Impacts from El Niño
in Indonesia, Philippines, and Vietnam

With the El Niño looming as a possibility this year, ECE's partner countries may draw on their research of the past 30-40 years of extremeclimate events and variability to get prepared for the impacts they might experience. Below is a brief summary of the impacts on the agriculture, water resources, and public health sectors. For detailed information on Vietnam and Indonesia, please check out the ECE Reports.

Using ENSO Forecasts for Anticipating Impacts on Agriculture

Extant climate impact assessment methodologies in the agricultural sector rely on indicators like rainfall distribution, crop monitoring, and water level positions in reservoirs, which give little lead-time before harvest to make resource management and disaster preparedness strategies. Upon receipt of climate information from meteorological departments, the agriculture departments need the capacity to interpret the data for use in decision-making. For example, in Indonesia, there is no specific unit in the Ministry of Agriculture to deal with climate. However, through its involvement with ECE, Indonesia has assembled a multi-sectoral team to produce ENSO forecasts and determine how the various scenarios would impact the agricultural sector.

In the Philippines, the ECE research study enabled the Bureau of Agricultural Statistics to assess the impact of ENSO on crop production by utilizing past data and cross-referencing it with ENSO indices. One particular study was conducted to attribute area-specific impacts to extreme climate event indicators, in order to develop planning tools. Results show that declines in gross value added (GVA) and production volume of four principal crops (rice, corn, sugarcane and coconut) coincide with El Niño years. The sharpest falls in GVA and production volumes of these crops occurred in 1982-83 and 1997-98, years with the strongest El Niño events of the century. On the other hand, the study also showed that livestock, poultry, and fisheries are not sensitive to extreme climate events.

Vietnam has reported that adopting a correlation coefficient methodology between ENSO indices and crop production indices, it is possible to establish some linkages. There is evident impact of ENSO on crop yield, gross, and cultivated areas. As part of their efforts to reduce the impacts of El Niño-related crises, agro-meteorological research centers have proposed cropping patterns as part of the ECE studies. For example, the calendar for rice outlines the province, growing duration, sowing data, and other key dates according to whether it is a normal, El Niño, or La Niña year.

Using ENSO Forecasts for Anticipating Impacts on Water Resources

Current climate impact assessment methodologies for water resources rely on indicators like rainfall distribution, water level monitoring on surface water storage structures and streamflow behavior. Studies in all three countries highlighted the impacts experienced at the extreme ends of the hydrological continuum, from droughts to floods. One of the usual secondary impacts from droughts are wildfires, which further tap limited water resources. At the other end, floods destroy homes and lives. In Indonesia, ECE provided an opportunity to collect data on streamflow and flood/drought incidences to assess the impact of extreme climate events. Results show that river flow variations are highly correlated with ENSO-related rainfall behavior, although a better data network and flood forecasting capabilities are need to increase forecasting skill.

The ECE research in the Philippines enabled the National Water Resources Board and their partners throughout the country to document past data and relate it to ENSO indices through correlation techniques. Significant associations between climate variability (rainfall) and hydrologic activity (reservoir inflow) exist at varying magnitudes in the study area, which helped to kick-start ongoing national investigations into how ENSO events would impact the water sector in the Philippines.

In Vietnam, a study was conducted on 15 large and small rivers in various agro-climatic zones to examine how ENSO impacts river runoff. Small and medium-sized rivers in Central Vietnam showed more significant sensitivity to ENSO than larger rivers in different regions. El Niño causes below normal rainfall, which in turn reduces the water available in irrigation systems in some central and upland areas of Central and Southern Vietnam. Given sufficient lead times, water managers would be able to prevent water stress at critical times of crop growth during the winter dry season.

Using ENOS Forecasts for Anticipating Impacts on Public Health

Current climate impact assessment methodologies for public health rely on indicators like rainfall distribution, temperature, humidity, vector population, and disease cycle. These provide little time before the outbreak of epidemics to undertake public health intervention measures. There are strong links between water and public health. One of the biggest impacts on public health has been water-borne illnesses during extreme climate events. Droughts can result in decreased water availability, contamination of water resources, and saltwater intrusion into freshwater sources. At the other end of the spectrum, floods may cause overflowing of sewage systems and cesspools, and may contaminate water with minerals and non-point pollution sources.

ECE research in the Philippines assessed the impact of climate variables such as temperature and relative humidity, and focused on dengue, cholera, typhoid, measles, and malaria in Metro Manila. Analysis of the time-series data from 1992-98 revealed a relationship between these variables and dengue, malaria, and cholera. Some ways to reduce these impacts on public health may be through identifying links between disease vectors and climate. For example, people are taught to store water during droughts, but these stagnant water sources can become breeding grounds for mosquitos that are the source of dengue and malaria. In their preparations for El Niño, public awareness campaigns may include information on how to store water properly to limit mosquito population growth.