Latin America: Scientists second-guessing the path of the whirlwind

IPS: Hurricanes Dean, Felix and Henriette caused dozens of deaths and millions of dollars worth of damage in the tropical zone of the Americas in just over two weeks. But worse may lie ahead, as five large cyclones are expected to materialise before the storm season is over.

…René Lobato and Ricardo Prieto, hurricane experts at the Mexican Institute of Water Technology, also told IPS that "We are half-way through this year’s season, and we can expect several more hurricanes, possibly five, more or less." William Gray, professor of atmospheric science at Colorado State University, ventured the opinion that while the 2007 hurricane season is "more active than normal," it will not turn out to be as "hyperactive" as those in 1995, 2004 and 2005.

…Nicaragua has suffered the most damage so far, with hurricane Felix leaving 40 people dead and nearly 200 missing. Mexico is in second place, with 11 deaths caused by hurricanes Henriette, on the Pacific coast, and Dean. Hurricane Dean also left nine people dead in Haiti, two in the Dominican Republic, one in St. Lucia and three in Jamaica.

Hurricane formation depends on a combination of factors: ocean temperatures above 27 or 28 degrees Celsius in near-tropical latitudes, causing evaporation and condensation, and a low-pressure centre, together with colder air contributed by the upper layers of the atmosphere.

…The two Mexican experts regretted that so far all attempts to artificially weaken hurricanes have failed. Over the last 40 years, different laboratories worldwide have been testing methods, such as using a liquid to prevent the evaporation of seawater, releasing soot in the vicinity of an incipient tropical storm to weaken its centre, and seeding nearby clouds with silver iodide, the only experimental method to have been field tested. But nothing has worked.

"Given this failure, the current approach is to work on improving preventive measures, including early warning systems, mass evacuations, insurance against losses, and budgeting for aid and reconstruction of affected communities," said Lobato and Prieto.

Over and above the possibility of discovering a method of taming the whirlwinds, the common sense measures undertaken "have been successful, and we hope that they will continue to improve in the short term," they said.