By Mario Osava
RIO DE JANEIRO, Jan 16 2002 (IPS)

The El Niño weather phenomenon that causes meteorological changes in various parts of the world by heating up the waters of the Pacific Ocean will reappear sometime between April and June this year, according to Brazil’s National Space Research Institute (INPE).

But the life- and harvest-threatening storms, flooding and drought will not be as bad as in 1997 and 1998, because this time around, El Niño will be “weak to moderate,” said Carlos Nobre, the head of INPE’s Weather Forecasting and Climatic Studies Centre.

The United States meteorology service announced last Friday that El Niño, a mass of warm water that appears in the equatorial waters of the Pacific Ocean and washes the coasts of South America, would return this year.

Temperature and salinity measurements carried out by the US meteorology service along the equator in the Pacific at depths of up to 500 metres show that a new El Niño is taking shape, although no signs have yet appeared on the surface, said Nobre.

The data, picked up by satellite and analysed on the basis of mathematical models, indicates that the phenomenon will show up a few months from now, “probably between May and June,” but also that this year’s El Niño will be much less destructive than the one that wreaked havoc in 1997 and 1998, he added.

The heating up of the equatorial waters of the Pacific Ocean tends to occur every two to seven years. The last episode, in 1997 and 1998, was one of the worst on record.

For over a year, the average temperature of the water trapped in the current was five degrees higher than the normal average of 23 degrees.

The effects were devastating, ranging from drought in northeastern Brazil, Australia, parts of Central America and the United States, southeastern Africa and Indonesia, to heavy rainfall in other parts of Asia, South and Central America and Europe, as well as an increase in storms.

El Niño killed thousands of people worldwide and left millions homeless, while causing tremendous damages to agriculture and leading to an increase in forest fires in the Amazon jungle region. The 1982-83 El Niño was also heavily destructive.

“The global impact caused by the energy released in the atmosphere” will not be so strong this time, said Nobre. But “there is nothing to guarantee that some areas will not be hit hard,” he warned. The impact could be heavy in some spots, although the overall global consequences will be milder than in 1997 and 1998, he explained.

Nor can the length of El Niño be predicted. The data indicates that its intensity will peak between August and October. But it could linger until 2003, which would lead, for example, to drought in northern and northeastern Brazil.

Rainfall will increase in the second half of this year in most of Brazil, especially the south, as well as in other countries of the Southern Cone of the Americas, Nobre predicted.

Prevention measures are thus indispensable. In Brazil, extreme weather conditions tend to especially affect the impoverished people of the semiarid northeast, where 12 million people depend on subsistence farming.

In the past, lengthy droughts drove people towards the southeast, then in the process of becoming industrialised, or towards the Amazon in the north in search of opportunities. But neither region now generates new jobs capable of absorbing a flow of migrants.

A moderate to severe El Niño nearly always causes drought and the consequent aggravation of the already high levels of poverty in northeastern Brazil, said Nobre.

But not all Brazilian meteorologists believe the reappearance of El Niño is imminent. Reports that a new El Niño is in the making have been issued since early last year, and its appearance was first announced for the second half of 2001, and then for early this year.

But the average temperature of the waters of the Pacific Ocean only went up one degree in the past few months, which is normal, said Vilson Ferreira with the Meteorological System of Parana, a farming state in southern Brazil.

Episodes of El Niño have varied in duration and intensity since the phenomenon began to be studied a century ago. From 1991 to 1995, a moderate heating of the equatorial waters of the Pacific was recorded.

Some researchers believe they are witnessing a gradual worsening of the El Niño phenomenon, parallel to the climate change caused by the greenhouse effect, which is a consequence of emissions of gases that trap heat within the earth’s atmosphere.

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