Rising global temperatures are likely to have played a part in creating the monster that was Hurricane Harvey, making it possible that the storm was a man-made disaster.
Hurricane Harvey pictured off the coast of Texas from the International Space Station [Image by NASA via Reuters]
When people call Hurricane Harvey unprecedented, they aren't exaggerating. Authorities have admitted that the storm was one that they were essentially not ready for. They haven't even seen a storm of this nature in their lifetimes. The National Weather Service has even had to update the color charts on their graphics in order to accurately represent how much rain has fallen over Texas.
“We have not seen an event like this,” said William Long, administrator of the Federal Emergency Management Agency. “You could not draw this forecast up. You could not dream this forecast up.”
At present, the focus is on relief efforts. However, even now, we're faced with a pressing question: does climate change have anything to do with the magnitude of Hurricane Harvey?
A man walks down a flooded street in his Texas neighborhood. [Photo by Scott Olson, Getty]
The short answer is this: climate change alone did not cause Hurricane Harvey. However, it's possible that climate change—as well as two hundred years of burning fossil fuels—made the hurricane worse than it could be. Climate change possibly contributed to turning Harvey into something of a man-made disaster.
Scientists identified three factors that turned the storm into a catastrophe. The first is the rapid intensification of the storm, the second is that it stayed over a single area, and the third is the forecast that rains will continue for days.
Let's look at the first factor. Hurricanes are supposed to grow weaker as they near land. However, Harvey's wind speeds intensified instead as it approached land. This is because wind speeds tend to intensify under warmer conditions. Sea water evaporation powers hurricanes, and warmer weather powers evaporation.
The second factor, meanwhile, tells us that Harvey stalled over one area and dumped all its rain over there. Usually, storms move on, hardly staying for too long over one place. This stops the storm from being too destructive. Harvey, however, didn't just bring severe rains—it also stayed in a single area. Scientists say that this is just pure bad luck, and that climate change likely didn't cause this to happen.
Rescue efforts [Photo by Luke Sharrett, Bloomberg, Getty Images]
The third factor is the continuous rains, which may actually set a new record. More rains fall across the globe as the planet grows hotter. Think of it this way: climate change makes the ocean surface hotter, which then feeds the storm with more water vapor. Climate change also makes the atmosphere warmer, making it capable of holding more moisture.
It's possible that the rains inundating Texas were made worse by rising global temperatures, and therefore by climate change. Climate change alone, as a single factor, can already increase rainfall by five to 10 percent. However, if you couple increased rainfall with unusually high ocean temperatures, the increase in rainfall could double.
No weather event can be attributed solely to climate change, which means that Hurricane Harvey isn't completely a man-made disaster. After all, there have been storms way before we started using fossil fuels. However, climate change likely makes these storms worse than what they could be.
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