Climate change is responsible for a lot of things, but it may not be directly responsible for Hurricane Harvey.
Harvey is not the first hurricane to hit the Texas coast. A deadly hurricane struck Galveston in 1900, and that storm caused thousands to lose their lives, primarily due to the lack of warning. Meteorology was not an advanced science at that time, and there were no satellites to track the storms as they moved across the Atlantic Ocean.
However, climate change is almost certainly responsible for the epic rainfall and catastrophic flooding endured by the cities struck by Hurricane Harvey.
“This is they type of event, in terms of extreme rainfall, that we would expect to see more of in a warming climate,” Dr. Friederike Otto from the University of Oxford told the BBC.
In fact, the rainfall was so extreme that the National Weather Service had to add new colors to its rainfall maps to account for the intensity of Harvey’s rains.
There’s a physical law called the Clausius-Claperyon equation, which says that a hotter atmosphere holds more moisture. For every degree Celsius in warming, the atmosphere can hold 7 percent more water, which makes rainfall events more extreme.
The temperature of the seas also contributes to the strength of hurricanes.
“The waters of the Gulf of Mexico are about 1.5 degrees warmer than they were from 1980 to 2010,” Sir Brian Hoskins of the Grantham Institute for Climate Change told the BBC. “This is very significant because it means the potential for a stronger storm is there, and the contribution of global warming to the warmer waters in the Gulf, it’s almost inevitable that there was a contribution to that.”
Although there have been slow-moving storms over Texas in the past, some scientists still attribute the intensity of Harvey to climate change.
Professor Stefan Rahmstorf from the Potsdam Institute for Climate Impact Research says that a general slowdown in atmospheric circulation in the earth’s middle latitudes could be a result of changing climate in other parts of the world.
“This is a consequence of the disproportionately strong warming in the Arctic,” Rahmstorf said. “It can make weather systems move less and stay longer in a given location—which can significantly enhance the impacts of rainfall extremes.”
Other scientists think it’s a stretch to believe that the slowly moving nature of the storm is caused by climate change. “I don’t think we should speculate on these more difficult and complex links like melting in the Arctic without looking into these effects in a dedicated study,” said Dr. Otto.
In addition to the damage caused by the flooding, pollution is causing the floodwaters to become a toxic stew of sewage, garbage, chemicals from more than 20 Superfund sites in the Houston area, oil and petrochemicals from damaged refineries, and much more, are causing concern.
“There’s no need to test [the water],” Houston Health Department spokesman Porfirio Villareal told the New York Times. “It’s contaminated. There’s millions of contaminants.”