Is Hurricane Frequency and Intensity Linked to Global Warming?

OCTOBER 21, 2005
By GREGORY J. RUMMO

...Is the earth’s warming anthropogenic (i.e. our fault) due to the overuse of fossil fuels? And if so, does that make the industrialized nations of the world guilty of spawning killer storms?  

          What do the letters X, Y and Z have in common? This year, they failed to make it as the first letters of potential names for hurricanes. W, and hence, Wilma is the last name on the list for 2005, a season that ties the 1933 record for the most named tropical storms.

            The Greeks will come running to the rescue should another storm be spawned in the waters of the inter-tropical convergence zone. Storm watchers should listen for Alpha, Beta and so on.

            Hopefully that won’t be necessary. But what if there are more tropical storms on the horizon? The hurricane season doesn’t officially end until November 30 so it seems likely this will indeed be the case.

            Some are making the claim this year's tropical onslaught is the result of global warming.

            The Pew Center on Global Climate Change is one such think tank. “Scientists believe that global warming will result in more intense hurricanes, as increasing sea surface temperatures provide energy for storm intensification.”

            Politics aside, it is an indisputable fact that the average surface temperature of the earth has increased by one degree during the 20^th century. One expects this would result in a concomitant rise in the temperature of the world’s oceans. Since warm water provides much of the fuel for a hurricane’s energy, the warmer the water over which a storm percolates, the greater will be its intensity.          

            Real Climate, a site that provides commentary on climate science “by working climate scientists for the interested public and journalists,” adds heat to the argument, stating, “The available scientific evidence indicates that it is likely that global warming will make—and possibly already is making—those hurricanes that form more destructive than they otherwise would have been.”

            Yet the Pew Center offers what could be taken as a disclaimer: “Although the average number of hurricanes between 1995 and 2005 is probably unprecedented, we have not seen a long-term increase in hurricane frequency during the 20th century overall. Instead, we have seen periods of high hurricane activity that last for several decades, followed by decades of low activity. The 1920s-30s and 1950s-60s were active periods. In 1995 we entered and are currently in the latest natural phase of high hurricane frequency, which is expected to persist for another decade or two.”

            So what is one left to believe? Is the earth’s warming anthropogenic (i.e. our fault) due to the overuse of fossil fuels? And if so, does that make the industrialized nations of the world guilty of spawning killer storms?  

            Dr. S. Fred Singer, president of the Science and Environmental Policy Project points out, “The bulk of the temperature rise in the 20th century took place before 1940 while most of the carbon dioxide emissions took place after 1940 and coincided with a slight cooling between 1940 and 1975.”

            So if the bulk of that warming happened before 1940, why weren’t the hurricanes during the 1930s or, assuming a lag for the oceans to heat up, the 1950s, of greater intensity than those that ravaged Florida, the Caribbean and other Gulf Coast states during the last decade?

            The NOAA Hurricane Center has a theory unrelated to global warming. The current active tropical hurricane cycle is a natural result of a “confluence of optimal ocean and atmosphere conditions [that] has been known to produce increased tropical storm activity in multi-decadal (approximately 20-30 year) cycles.” And while the residents of the Caribbean and Gulf Coast regions have suffered, the factors that increased the frequency of hurricanes in the Atlantic since 1995 produced “a marked decrease in hurricanes in the eastern Pacific hurricane region.”

            “Similar conditions also produced very active Atlantic hurricane seasons during the 1950s and 1960s. In contrast, the opposite phase of this signal during 1970-1994 resulted in only three above-normal Atlantic hurricane seasons in the entire 25-year period.”

            Despite increases in atmospheric carbon dioxide during the fuel-inefficient, gas-guzzling 70s, 80s and mid-90s, 22 of those 25 years exhibited below-normal hurricane activity.

            There is too much conflicting data leading to poorly formulated cause and effect relationships for me to embrace global warming as the culprit behind hurricane frequency or intensity.

            But let’s assume the global warming alarmists are right after all. I wouldn’t break out the sunglasses and the Coppertone just yet. But there is some good news amidst their prognostications of global doom and gloom.

            The National Weather Service weighed in last week with its forecast for this winter’s weather. The consensus of the meteorological gurus is for warmer than normal temperatures.

            In a year where the price of oil is at an all-time high and natural gas prices are up 48 percent over last year’s heating season, maybe there’s a silver lining in those rain clouds after all. n