Of heat and hurricanes

Andrew Blitman
Andrew Blitman

As Florida braces itself for the peak of the hurricane season, the effects of global warming on storm intensity and frequency have yet to be revealed – until now. According to a study released last Wednesday, the greenhouse effect will likely enhance the strength of the most powerful cyclones.

Over the past 100 years, human industrial and agricultural activities have released considerable amounts of carbon dioxide and methane into the skies. Greenhouse gases, carbon dioxide and methane accumulate in the upper levels of the atmosphere, forming blanket-like layers that trap heat and sunlight. In small quantities, these gases perform a valuable service, warming the Earth just enough so that it can be habitable to life. At modern levels, greenhouse gases absorb heat more thoroughly, raising the planet’s average temperature and wreaking havoc on global climate patterns.

The recent study warns that even a marginal increase in ocean temperatures (roughly two degrees Fahrenheit) could result in a 31% rise in the number of category 4 and 5 storms. And according to records of Atlantic hurricanes, we have seen a gradual, dangerous boost in the strength of cyclones since the 1970s because of warming seas.

The frequency of hurricanes, called cyclones in the Pacific and monsoons in the Indian Ocean, saw no change. However, satellite evidence from the last 25 years has revealed a disturbing trend – an increase in wind speed among the most powerful maelstroms. Such an upsurge would have serious repercussions. Storms like Katrina, Wilma, and Ike could become the norm. And if that happened, insurance prices in hurricane zones would skyrocket. Mixed with the ongoing mortgage crisis, the already difficult task of buying a house in the south might become almost impossible.

During the last century, the average global temperature rose almost one degree Celsius. While a one-degree change might not sound significant, it is believed that a ten-degree hike caused the Permian mass extinction 250 million years ago (wiping out 90% of life alive at the time). By 2100, it is speculated that the global mean temperature will increase between 2 and 4 degrees Celsius. Our grandchildren could face monsoons stronger than anything we have seen before or since.

Thankfully, though, the new study is not definite. There is still a wide range of uncertainty regarding global warming’s effects on the Earth’s circulatory system (air and ocean currents). Plus, humanity’s habits are changing. If alternative energy technology becomes dominant soon, the worst warming could be avoided.