The name itself still has power. The mention of this storm brings back a complex slew of memories—both horrific and transformative. It marked a death and rebirth for New Orleans. Because of this, we as a city have a unique, ingrained respect for the power of hurricanes. So sit down—with global temperature increases, hurricanes will be getting worse, much worse. This is due to a variety of factors, many of which stem from anthropogenic climate change.
It is well known that warm water strengthens hurricanes. This is because hurricanes gain strength by transferring heat from the water’s surface to the upper atmosphere, causing a pressure gradient which creates strong cyclic winds. Coinciding with global temperatures, average sea surface temperatures are on the rise. As future cyclones make their way through the Atlantic, the warmer water will allow for more heat to be displaced and consequently nurture stronger hurricanes. Using complex simulations, many climate scientists expect a 90% increase in Category 4-5 hurricanes by the end of this century. This will be detrimental to the people and the economy of the Gulf Coast, as storms of this strength require intense preparation, evacuation, or both. Another result of warmer waters is more humidity, which is predicted to cause a 20% increase in near-storm rainfall. The destructive power of rain was exemplified by Hurricane Harvey, a storm that quickly jumped from category 1 to 4 when it drudged through an area of water 1.5 degrees warmer than the surrounding gulf waters. This warm spot, or eddy, not only allowed for an increase in intensity, but a great accumulation of moisture which allowed for the record breaking rainfall. This should be of great concern since the average Gulf of Mexico water temperature is predicted to increase by .36 degrees every decade. This leaves 40 years before the gulf’s average temperature is the temperature of the current “warm spots”–a very frightening thought. These increases in intensity and rainfall are not the only problems presented by a warming ocean.
The sea level is rising. Increased thermal expansion of sea water and the melting of land-based ice combine to cause an ever increasing rate of sea level rise. This phenomenon poses a dual threat to Louisiana by both increasing rates of coastal land loss and adding to the height of storm surges. This is a deadly combination because our greatest protection from storm surges is our coastal wetlands: the general rule is every 2.7 miles of marshland reduces storm surge by about a foot. Therefore, a reduction in marshland, all things equal, will allow for a much more imposing storm surge. Additionally, the rise in sea level allows for the storm surge itself to have a heightened starting point, causing a higher total surge and allowing for further penetration into the mainland. These two variables multiply: higher storm surge with less protection equals more destruction. Similarly, the blend of increased intensity, rainfall, and storm surge makes for potential devastation greater than the sum of its parts.
The PDI scale was created to quantify the multiple variables of hurricane strength, duration and frequency, giving a full spectrum view of the hurricane’s power. This aggregate measurement brings about the most somber predictions yet–some predicting a 300% increase by 2100. However, the PDI predictions vary greatly and scientists are conflicted on what the actual number will be, but what we do know for certain is that it will increase and it is because of our species’ actions. We are causing climate change and are consequently increasing the frequency and severity of extreme weather events. Already we are seeing hurricanes like never before; the average strength of hurricanes has been steadily increasing since the 70’s, allowing for a higher level of possible devastation. Because the statistical distribution of hurricane severity lies on a bell curve, a small shift in the average can cause a tremendous change at the extremes. We must take action now to slow climate change, not only to save the environment, but to save ourselves from the future super weather events of our own creation.
We are poisoning Gaia. In Greek mythology, Gaia is the personified form of the biosphere, a type of Mother Earth deity. This unification of the earth into a singular super-organism was revived with the theory that the earth is a type of synergistic system, self-regulating in a struggle to maintain conditions conducive to life: properly named the Gaia Hypothesis. This theory may be slightly pseudoscientific but serves as a good metaphor. We as a species are a part of this super-organism, not the masters of it. Because of our disregard for the natural order and our desire to exploit, we are causing a type of inflammatory response—a fever of sorts. The temperature is rising. We must outgrow this attitude of dominion we have over Gaia and learn to live in balance with her; for climate change will either serve as a wake up call or a eulogy.
The push for a sustainable world must come from the grassroots: as the elites that hold the reins of industry benefit from the cause and are immune to the disasters. They have the means to relocate, while we, the everyday people, are damned to the ever expanding disaster zones. Their voice is strong, as they own the politicians and control the media, but together our voice can be stronger. We must unite, recognizing that this issue is not democrat vs. republican: it is love vs. greed—understanding vs. ignorance, and the choice is clear.