As hurricane Irene moves slowly up the east coast, you can bet that everyone on this side of the country is bracing for the worst. Aside from the fact that NYC is in a state of emergency in light of a Category 1 hurricane that is getting a lot worse, the intensity of recent hurricanes can actually be linked to some very alarming changes in the Earth’s climate.
“Hurricanes, typhoons, and cyclones have always bedeviled coasts, but global warming may be making matters worse,” states a report by the Union of Concerned Scientists. “Sea level is rising and will continue to rise as oceans warm and glaciers melt. Rising sea level means higher storm surges, even from relatively minor storms, which increases coastal flooding and subsequent storm damage along coasts. In addition, the associated heavy rains can extend hundreds of miles inland, further increasing the risk of flooding.”
Recent studies have discovered a disturbing link between the destructive power of hurricanes and higher ocean temperatures, driven in large part by global warming. The population growth along coastal regions, especially in big cities like NYC and Washington DC, place more people and structures in the path of tropical storms, and in turn, increase the risk of “casualties, property damage, and financial hardship when these storms make landfall.”
In a nutshell, the three main factors that contribute to a tropical storm’s intensity are warm ocean temperatures (hurricanes occur when temperatures exceed 79 degrees Fahrenheit/26 degrees Celsius), low vertical wind shear, and high humidity.
How does global warming come into play? Factors like ocean heat content and water vapor have both increased over the past several decades, primarily due to the burning of fossil fuels and continual deforestation. This has in turn increased carbon dioxide emissions in the atmosphere. According to the study, “CO2 and other heat-trapping gases act like an insulating blanket that warms the land and ocean and increases evaporation.” This has directly lead to a significant increase in storm intensity and tropical storm occurrences since the 1970s.
“It is likely that hurricane/typhoon wind speeds and core rainfall rates will increase in response to human-caused warming,” stats a report by the US Global Change Research Program. “Analyses of model simulations suggest that for each 1°C increase in tropical sea surface temperatures, hurricane surface wind speeds will increase by 1 to 8 percent and core rainfall rates by 6 to 18 percent.”
But that’s not all. The Union of Concerned Scientists has also collected other disturbing data as well:
Scientists have looked at potential correlations between ocean temperatures and tropical cyclone trends worldwide over the past several decades. A 2005 study published in the journal Nature examined the duration and maximum wind speeds of each tropical cyclone that formed over the last 30 years and found that their destructive power has increased around 70 percent in both the Atlantic and Pacific Oceans. Another 2005 study, published in the journal Science, revealed that the percentage of hurricanes classified as Category 4 or 5 (based on satellite data) has increased over the same period. The findings from both studies correlate with the rise in sea surface temperatures in regions where tropical cyclones typically originate.
The same study created a model simulation of possible future storm trends. A one percent annual increase of CO2 emissions in the atmosphere over the next 80 years will continue to produce more intense storms and will increase rainfall by about 18 percent.
Although the chances of getting hit by a pre-historic “super hurricane” (yes, there is a field of study — Paleotempestology — that focuses on that) anytime soon are very slim, the findings of these recent studies should not be overlooked. One need only look at the tragic effects of Hurricane Katrina and the panic that Hurricane Irene is causing in major cities to know that climate change is not simply a political talking point, but a very real danger.
The shocking truth about global warming emissions is that they remain in the atmosphere for decades. But one of the best ways we can make sure that we’re doing our part in taking care of the environment is by investing and promoting alternative forms of energy and environmental sustainability efforts The technology to increase energy efficiency and reduce dangerous carbon emissions is readily available. Let’s just hope we can implement a significant change for the well being of future generations.