The frequency of lightning will increase 30 percent over the next 25 years in the Brazilian state of Sao Paulo, quadrupling the losses to electrical utility infrastructure because of more blackouts, according to the national space research institute, ELAT. Losses to Sao Paulo state will be equal to those of the entire country today by 2030: 185 million dollars annually.

''Global warming, La Niña climate phenomenon in the Pacific Ocean, and increased heat in cities of more than 500,000 residents will be the factors behind the increase,'' Osmar Pinto Junior, head of the ELAT atmospheric electricity division, told Tierramérica.

The ELAT prediction model is based on ''conservative'' projections, with a temperature increase of just half a degree centigrade and moderate effects from La Niña.

Global warming is likely to affect all tropical regions of South America in a similar way, meaning more lightning strikes across the continent, said Pinto.