ECO-EXCHANGE -- Last year was the fifth hottest on record, which has done more to convince scientists that global warming is a reality than the fact that 1998 was the hottest year ever. That is because 1998 was a year of El Nino, a regularly occurring weather pattern that usually increases temperatures. But 1999 was La Nina year, when a different weather phenomenon is supposed to cool temperatures. Instead, the National Center for Atmospheric Research in the United States reported that land temperatures were slightly warmer than normal.

Like nations everywhere, the countries of Central America are trying to come to grips with how they should react to global warming. The change in temperature is associated with destructive storms, like Hurricane Mitch, which battered Central America in 1998, killing an estimated 11,000 people. The surprising intensity of the storm is likely related to global warming, according to the Worldwatch Institute in Washington, D.C. But the resulting destruction was mainly due to deforestation, as the heavy rains falling on denuded hillsides caused lethal mudslides.

"We can attribute more than 90 percent of the cause of climate change to the way we human beings have been managing our natural resources," notes Aristides Loriesse, assistant director of the Center of Water of the Humid Tropics and the Caribbean (CATHALAC in its Spanish acronym). He believes the region will continue to suffer from the effects of climate change in coming years. "Unfortunately, we have so degraded our atmosphere that it will take nature a long time to correct our errors," he explains. "We must learn how vulnerable we are and how we can mitigate the impacts."

Researchers affiliated with CATHALAC, which is based in Panama, are studying how to predict and react to climate change so the region's water and other natural resources can be better managed.

Economist Danaik Garcia, of the Agriculture Insurance Institute in Panama, points out that the farmers in Central America depend on regular rains, since the majority of the region lacks irrigation systems. Information form CATHALAC has helped the institute advise its clients when they can expect droughts and heavy downpours.

Global warming is mainly due to increasing amounts of polluting gases, particularly carbon dioxide (CO₂), which human activities pump into the atmosphere. Worldwatch Institute reports that 200 years ago, at the dawn of the Industrial Revolution, the CO₂ concentration in the atmosphere was an estimated 280 parts per million. By 1959, when accurate measurements were first taken, it had reached 316. In 1998, the level was 367, an increase of 17 percent in just 39 years.

The Central American Commission for the Environment and Development (CCAD) is studying the region's gas emission and the capacity of its forests to absorb CO₂. According to CCAD's Marco Gonzalez, El Salvador and Honduras are currently net producers of the gases that cause global warming. Most of the energy in these two Central American countries is provided by non-renewable fossil fuels, he says, adding, "Moreover, there have been a huge number of forest fires, which also emit gases."

He points to three factors that will help check CO₂ emissions in Central America: energy efficiency and controls on transportation and industry. He says that conserving forests mitigate global warming only because "land with forests means the ground is not being used for other purposes that emit CO₂."

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