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GEO-3: GLOBAL ENVIRONMENT OUTLOOK  
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Hydrometeorological events

The best known hydrometeorological event is the El Niņo phenomenon, the impacts of which can be severe. For example, after the El Niņo of 1983, Peru's GDP fell by 12 per cent, mostly because of a reduction in agricultural output and fishery. The national economy took a decade to recover. Damage in the Andean Community countries (Bolivia, Colombia, Ecuador, Peru and Venezuela) due to the 1997/98 El Niņo was estimated at more than US$7 500 million (CEPAL 1999).

El Niņo and epidemic diseases

Cyclical temperature and rainfall variations associated with El Niņo are particularly important since they can favour the development and proliferation of vectors of epidemic diseases such as malaria, dengue fever, yellow fever and bubonic plague (WHO 1999). In South America, the most severe outbreaks of malaria generally occur a year after the beginning of an El Niņo event, whether associated with an increase in rainfall (as in 1983 in Bolivia, Ecuador and Peru) or with a reduction in rainfall and run-off (as in Colombia and Venezuela).

A similar link has been suggested between the warming of superficial oceanic waters by El Niņo, the proliferation of marine algae, and the appearance of cholera in South America in 1992. The impact of extremes in precipitation (both too much and too little) is also important in the transmission of water-borne diseases such as cholera, gastrointestinal infections and various types of diarrhoea. There were outbreaks of cholera in 1997-98 in Honduras, Nicaragua and Peru related to the increase in precipitation, associated with El Niņo (WHO 1999, PAHO 1998).

Most countries in Central America and the Caribbean are within the hurricane belt, on both the Atlantic and Pacific coasts. Hurricane Mitch, which struck the region in 1998, affecting mostly Honduras and Nicaragua, killed more than 17 000 people and left three million homeless with damage estimated at US$3 000 million. The hurricane also caused fatalities and serious environmental and economic damage in Costa Rica, Dominican Republic, El Salvador and Guatemala (CRED-OFDA 2002).

The 1999 floods on the northern coast of Venezuela also had a strong impact, with damage estimated at more than US$ 3 200 million or 3.3 per cent of the country's GDP (World Bank 2000). In the state of Vargas, the hardest-hit area, more than 230 000 jobs were lost. The state of Miranda was also badly hit: the El Guapo dam collapsed, causing water shortages and 60 per cent of crops were reported lost (MoPD Venezuela 2000). It is estimated that there were 30 000 deaths, 30 000 families left homeless and more than 81 000 dwellings destroyed (IFRC 2002).

Ecological and social impacts of earthquakes in El Salvador

The series of earthquakes that shook El Salvador in early 2001 began with one of 7.6 on the Richter scale that was initially considered an isolated event. However, it was only part of a series that spanned weeks and demonstrated the complex social and ecological implications of such events. Besides the loss of life and infrastructure during the original series of earthquakes, there has been a long-lasting impact on people and ecosystems. For example, the artisanal fishery lost an essential part of its docking infrastructure as well as service infrastructure for processing fish and transporting it to the market on land. A total of 30 772 farms were damaged and farmers were forced to wait for three months for the rains because they did not have the funds to repair their damaged irrigation systems. The destruction of 20 per cent of the country's coffee processing plants severely affected the jobs and income of thousands of rural families in a country that was also affected by Hurricane Fifi in 1974, civil conflict between 1978 and 1992, the 1986 earthquake and Hurricane Mitch in 1998.

Source: UNICEF 2001