Heat Adds Power to Storms

Although it may not be scientifically possible to attribute any individual weather event to global warming, that hasn't stopped a discussion about extreme weather and climate change from evolving out of the disaster that was Hurricane Katrina.

Spurred on by a cabal of climate change skeptics who have gone to great lengths to deny any connection between hurricanes and global warming, serious scientists without other agendas are now weighing in on the discussion. That's good news, because there has been a sore need for honest discussion about global warming in the United States for some time.

Hurricanes happen, with or without humans disrupting the climate. However, there is good evidence to suggest that hurricanes will become more intense as we continue to change our atmosphere. Kerry Emanuel, of the Massachusetts Institute of Technology, has conducted the most comprehensive analysis of hurricane power over the past 30 years. His paper, prophetically published pre-Katrina this August in the journal Nature, reports: "My results suggest that future warming may lead to an upward trend in tropical cyclone destructive potential, and - taking into account an increasing coastal population - a substantial increase in hurricane-related losses in the twenty-first century."

Scientific theories and computer models have both predicted an upward trend in the power of hurricanes as the climate heats up. However, Dr. Emanuel points out that detection of actual trends for hurricane activity has focused mostly on their frequency - not their power. His work suggests that hurricanes have become markedly more powerful and longer-lasting since the 1970s.

Those observations certainly correspond with the events that pushed Katrina from a category one to a category five hurricane in a matter of days. This August, water in the Gulf of Mexico was unusually warm - two to three degrees Celsius warmer than average. As Katrina passed over the Gulf from Florida to Louisiana, she sucked up all that heat and grew into a monster.

This doesn't mean that global warming caused Katrina, but it is a sobering reminder of what we can expect in the future if we continue to drive up global average temperatures. More heat means warmer water, which increases the potential for devastating storms like Katrina.

How we deal with this problem is a political issue, not a scientific one. We could do nothing and hope for the best, or we could tackle the problem head on. Tackling the problem requires a two-pronged approach. First, we must reduce the emissions that are changing the climate and second, we must prepare for a warmer climate, because even if we stopped putting out heat-trapping gases today, our climate will continue to warm for years to come. That means we need to brace ourselves for potentially more violent weather.

One of the best ways to do that along our coastlines is to repair degraded ecosystems. Along the Gulf Coast, for example, restoring sandy barrier islands and marshy bayous would help protect coastal communities from storm surges. Similarly, protecting coral reefs and mangrove forests would help protect low-lying countries like Bangladesh from cyclones. Restoring and protecting forests in general helps stabilize soils and reduces the potential for flooding.

For years, scientists warned politicians about what would happen when a hurricane struck New Orleans. It was not an "if," they said, but a "when." Those concerns filtered all the way up to the White House where they fell on deaf ears. Now, the worst has happened and senior politicians are shrugging their shouders as if there was nothing they could have done.

Scientists are offering similar warnings about climate change, and the White House's response has been even cooler. This time, however, with discourse opening up about the connection between global warming and extreme weather, the public may not be as willing to accept inaction as an official policy.

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