Commentary and Opinion

COVERING TAMPA BAY AND ITS WATERSHED

Our subscribe page has moved!

Please visit baysoundings.com/subscribe to submit your subscription request.

commentary & opinion

Is Global Warming Causing an Increase in Hurricanes?

Benjamin Preston, Senior Research Fellow Pew Center on Global Climate Change In the wake of Hurricanes Charley, Frances, Ivan and Jeanne, the question on everyone's tongue, particularly in Florida, is "What's going on?" Meteorologists at every news organization have provided brilliant displays of the latest weather imaging technology and talked at length about tropical waves, sea surface temperatures, and steering currents. Many sitting at home, however, are thinking about another climate phenomenon - global warming.

The world's leading climate research institutions, such as the World Meteorological Association and the United Nation's Intergovernmental Panel on Climate Change, have said that severe weather events - heat waves, droughts, and floods - are on the rise and will continue to increase in the decades ahead. It's no wonder that in searching for the culprit behind billions of dollars in hurricane damages over the past month, many are casting suspicious glances at global warming.

In searching for the cause, however, we should take time to reflect on hurricanes past. Active hurricane seasons appear frequently in historical records. If you think this year has been bad, consider the end of the 19th century. In 1886, the United States was struck by no fewer than seven hurricanes - a record that has stood ever since - and the 1890s were one of the most active decades of the past 150 years. Even Florida's recent misfortunate is not without precedent: three hurricanes struck Florida in 1926 and another three in 1964.

If you think this year has been bad, consider the end of the 19th century. In 1886, the U.S. was struck by no fewer than seven hurricanes - a record that has stood ever since. Hurricane frequency and intensity vary over time, as a result of natural cycles in the climate system, specifically the North Atlantic Oscillation (NAO). When the NAO causes higher ocean temperatures, hurricanes tend to grow larger. Higher temperatures also influence the track of hurricanes, increasing the chance of hurricanes making landfall in the United States. Cooler ocean temperatures are associated with smaller hurricanes, with fewer reaching the United States. The most recent cool phase of the NAO ended in 1995, and with it ended a long period of low hurricane activity.

Since then, the United States has experienced more active hurricane seasons, except during El Nino events, which hindered hurricane formation in the Atlantic in 1997 and 2002. Hurricanes Charley, Frances, Ivan and Jeanne, despite causing billions of dollars in damage already, still represent a hurricane season that is within the bounds of natural climate variability. There is no evidence that global warming has played a part in hurricane activity up to now.

Nevertheless, it's important to realize that the past is not a perfect indictor of what the future will bring. With high ocean temperatures the norm once again, the active hurricane seasons we have been experiencing recently are expected to continue for the next few decades. In addition, the growing human influence on the climate system is increasing the likelihood that future hurricane seasons will look like the one we're experiencing now.

We know we are warming the world and its oceans. And we know that higher ocean temperatures favor larger hurricanes and more hurricanes reaching the United States. As global warming continues, more and more of the hurricanes making their way toward our coastlines may be category 3-5 storms rather than category 1-2 storms, and the after-effects of such big storms - intense precipitation, floods, tornadoes - will be also worse.

Dealing with the widespread destruction of a category 3-5 hurricane in a highly populated area will always be difficult. However, complacency in the face of such storms increases the challenge. Development in coastal areas is booming as more people, and more wealth, are concentrated along the water's edge. This development continues under the assumption - or hope - that the next big storm will strike at another time in another place. Mother Nature has just demonstrated the dangers of such complacency, leaving us to sort out what we did wrong as we try to pick up the pieces.

We can't prevent the formation of hurricanes due to natural climate variability, and it's already too late to prevent some global warming, but we can start planning accordingly. Now that hurricanes are expected to be common along U.S. coasts for years to come, we should rethink building codes, disaster management plans and funds, and public and private insurance programs to ensure we're building communities that are less vulnerable to hurricane damages rather than more.

EDITOR'S DESK

I have enough trouble staying on top of dust and dander from my own backyard without having to slay dust bunnies from Africa.

As if we needed further proof that we're all neighbors on this incredible planet, the massive dust storms rising out of Africa each summer and hitching trade winds to the Caribbean and Florida are sobering reminders.

While the phenomenon is not new - dust has been blowing for millennia, after all - dust clouds have intensified in recent decades following a prolonged drought in northern Africa. The same iron-rich plumes that contribute to everything from stuffy heads to asthma also produce some of the suncoast's spectacular red sunsets and may cause red tides.

I'll never look at dust, or a sensational summer sunset, in quite the same way.

It's estimated that millions of tons of African dust reach Florida shores each summer, at times invading every state east of the Rockies. The dusty scourge is mostly fine clay and silica, and has been known to contain everything from DDT, mercury and arsenic to camel and goat dung.

More recent examination of the particulates by Tampa Bay researchers has documented the presence of live bacteria and fungi, microbial 'riders of the storm' responsible for a host of maladies from coral disease to human respiratory ailments.

Local science sleuths, including USGS researcher Eugene Shinn, are hot on the dusty trail, but say research is underfunded and undervalued.

While downwind nations are at greatest risk, the U.S. can no longer afford to turn a blind eye to the potentially ill winds and the far-reaching implications for human health and the environment.

Bay Soundings will continue to examine this issue in future editions of the publication.

On a brighter note, America's love affair with automobiles is about to take some exciting turns (see Hybrids). New hybrid engine cars are hitting the market in force and living up to the hype.

Not only are they high-efficiency, they're high performance - proving you can get great fuel economy without sacrificing power and pickup. And you'll be seeing more and more hybrids - as many as 20 models by 2006 - as drivers, weary of high gas prices and attracted by declining prices for hybrid cars, get behind the wheels.

It's a brave new world with plenty of challenges, but the road ahead is filled with fabulous new technologies that hold out the promise of clearer skies ahead.

- Mary Kelley Hoppe