Warmer waters are fueling Hurricane Harvey’s power

The hurricane is expected to drop up to 35 inches of rain in Texas.

Rainfall predictions for Texas with Hurricane Harvey. CREDIT: National Weather Service
Rainfall predictions for Texas with Hurricane Harvey. CREDIT: National Weather Service

The strongest storm to hit the coast of Texas in 47 years is barreling toward Houston and is expected to make landfall late Friday or early Saturday morning. Hurricane Harvey has already sparked evacuations and a broad state of emergency, while authorities await “life-threatening” conditions and the potential for massive flooding. It is expected to be the first Category 3 hurricane to hit the United States in 12 years.

The hurricane’s strength can be directly tied to our warming climate. Waters in the Gulf of Mexico, where Harvey is forming, are five degrees higher than normal. Warm waters help fuel hurricanes, increasing wind speeds while allowing the air to hold more water, which will eventually fall as rain.

“Since Harvey is embedded within light shear [low surrounding wind speeds] and moving over warm waters, additional strengthening is anticipated before landfall in about 24 hours,” the National Hurricane Center said in a post at 4 a.m. ET on Friday (emphasis  added). “Thereafter, gradual weakening is forecast but since a good portion of the circulation will remain over water, the weakening process could be slower than normal.”

The outlook is not good. “Harvey is expected to be a major hurricane at landfall, bringing life-threatening storm surge, rainfall, and wind hazards to portions of the Texas coast,” the National Weather Service says in its advisory.  “Devastating and life-threatening flooding is expected across the middle and upper Texas coast.” The center of the storm is currently on track to make landfall just north of Corpus Christi, but bands of rain will extend outward for miles. 

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Harvey was upgraded to a Category 2 hurricane Thursday night, and it is widely expected to be upgraded again by landfall to a Category 3, with wind speeds between 111 and 129 miles per hour. According to NOAA, in a Category 3 storm, “devastating damage will occur: Well-built framed homes may incur major damage or removal of roof decking and gable ends. Many trees will be snapped or uprooted, blocking numerous roads. Electricity and water will be unavailable for several days to weeks after the storm passes.”

Warm air can hold more water than cool air, and the main concern for Harvey is the possibility for massive flooding. Once Harvey hits land, it is expected to stay in place for up to three days, potentially dropping up to 35 inches of rain in some locations. That will be especially problematic if the storm turns north and hits Houston directly. Houston is the country’s fourth-largest city by population, and one of the country’s largest by area. Much of that area is paved — Houston reportedly has 30 parking spaces per resident. Since the city’s last major storm, in 2001, even more of the city has been developed.

Cities are uniquely vulnerable to storm surge and flooding, because water has nowhere to go. Superstorm Sandy, which swamped New York City and surrounding areas in 2014, had been downgraded to a Category 2 storm when it hit the East Coast, but it brought a massive storm surge. In New York alone, at least 53 people died. Economic costs were roughly $19 billion — trading was suspended for two days, and thousands of homes were destroyed. 

A Propublica/Texas Tribune project from last March detailed Houston’s vulnerability to a major storm. The title of the project is “Hell and High Water,” and it chronicles what could happen. “A major hurricane here could bring economic and ecological disaster,” they wrote, including flood damage, destruction of entire low-lying neighborhoods, devastation to Galveston, and a massive disruption of our country’s oil and shipping industries:

Such a storm would devastate the Houston Ship Channel, shuttering one of the world’s busiest shipping lanes. Flanked by 10 major refineries — including the nation’s largest — and dozens of chemical manufacturing plants, the Ship Channel is a crucial transportation route for crude oil and other key products, such as plastics and pesticides. A shutdown could lead to a spike in gasoline prices and many consumer goods — everything from car tires to cell phone parts to prescription pills.

As Texans flee for higher ground, the oil and gas infrastructure that lines the state’s coast will remain in the heart of the storm. There is a bitter irony to the idea that a storm, strengthened by human-caused climate change, carries the potential to destroy the very oil infrastructure that has contributed so much warming to our world.

As Propublica wrote last year, “Scientists tell us that it is simply a matter of when, and not if, a monster storm is coming for Houston. Given this reality, this project examines why so few steps have been taken to safeguard this valuable and vulnerable region.”

More than a year later, it seems we’re moving away from preparation. President Donald Trump recently reversed flood protection rules for federal building projects, allowing more development — with taxpayer dollars — to be put at risk.

Instead of action, we’re left with thoughts and prayers.