Houston: A Global Warning

The devastation of Hurricane Harvey marks a turning point and raises the terrible possibility that we've entered the age of climate chaos

People walk down a flooded street as they evacuate their homes after the area was inundated with flooding from Hurricane Harvey on August 28th, 2017 in Houston, Texas. Credit: Joe Raedle/Getty

Let there be no doubt: the horrific damage wrought by Hurricane Harvey was an almost entirely man-made catastrophe, one fingerprinted by all-too-human neglect, corruption and denial. If we needed a reminder of the power of water to destroy an American city, Hurricane Harvey provided it. In Houston, a fast-growing metropolis of more than 2 million people, it wasn't the wind that was so damaging, or a storm surge pushing in – it was just water everywhere, falling for days in biblical torrents and transforming highways into rivers, flowing into homes, killing dozens, sending tens of thousands of people fleeing for higher ground. It was a terrifying and deadly display of what happens when nature collides with urban life on a planet radically altered by climate change.

Harvey is the worst rainfall event ever in the continental U.S. More than 50 inches of rain deluged parts of Houston. The amount of water that poured from the sky is difficult to conceptualize. By some estimates, 19 trillion gallons of water fell in five days. That's roughly a million gallons of water for every person in southeastern Texas. Harvey's economic toll will likely exceed Katrina as the most expensive disaster in American history.

Hurricanes are nothing new in Texas. In 1900, a hurricane hit Galveston, causing 15-foot storm surges, killing an estimated 8,000 people. But given what scientists know now about how rising CO2 levels impact the climate, it's wrong to dismiss Harvey as a purely "natural" event.

First, thanks to increasing carbon pollution, the waters in the Gulf of Mexico, over which Harvey formed, were about five degrees higher than average. "As the world warms, evaporation speeds up," explained climate scientist Katherine Hayhoe. So on average, there is more water vapor in the air now to sweep up and later dump over land. Also, because hurricane winds are generated by the difference in temperature between the atmosphere and oceans, the warmer waters tend to intensify a hurricane's gales.

Second, a warming climate fuels sea-level rise, which is the result of the thermal expansion of the oceans and the melting of glaciers. Higher seas mean bigger storm surges, which can be devastating (recall the destruction wrought by Hurricane Sandy). But when the seas are higher, it also means that it is more difficult to drain rainwater into the ocean. And that is what happened in Houston: The water had nowhere to go.

"19 trillion gallons of water fell from the sky in five days, roughly a million gallons for every person in southeast Texas."

This was a disaster foretold. In the 1990s, climate scientist Wallace Broecker said that the Earth's climate was "an angry beast" and that by dumping massive quantities of CO2 into the atmosphere, we were "poking it with sticks" – and nobody could say how the beast would react. That's where we are today. Harvey is the third 500-year flood to hit the Houston area in the past three years. Ten years ago, most scientists thought we might see three feet of sea-level rise by 2100. Now, estimates by the National Oceanic and Atmospheric Administration say the worst-case might be eight feet by 2100, while former NASA scientist James Hansen argues that it could be 10 feet or more. The larger reality is, we're moving into an era of unknown impacts, where it is impossible to say how fast our world will change, or how bad it will get. "We are dealing with an event that no human has ever witnessed," Penn State scientist Richard Alley recently told me as we discussed the collapsing Antarctic ice sheets. "We have no analog for this."

At the same time, we've allowed cities like Houston to become empires of denial. If you set out to design a metropolis that is poorly adapted to the future, you couldn't do much better than Houston. Consider the rate at which it's paved over the wetlands, nature's sponges for absorbing water. Thirty percent of the surrounding coastal prairie wetlands was developed between 1992 and 2010, creating what amount to concrete catch basins that capture the water and funnel it toward destruction. In Houston, the bayou is just a place to drive your Lexus – this is a city that's said to have 30 parking spots for every resident.

Houston proudly touts itself as "the City With No Limits," playing up its Wild West heritage of endless land and opportunity. But it is also the largest U.S. city to have no zoning laws, meaning you can build whatever you want, wherever you want. While that makes developers happy, it's not how you build a climate-resilient city. According to a Washington Post investigation, more than 7,000 residential buildings have been constructed in 100-year FEMA-designated flood plains since 2010. But given that FEMA's flood maps haven't been updated to reflect sea-level rise and other factors, the actual number of new buildings constructed in high-risk places is likely much larger. And this is true not just in Houston but in Miami, South Carolina and every other flood-prone region. Ten years ago, Houston officials banned development in areas with high risk of flooding. But developers sued, until the policy was weakened by the City Council. Government officials tried putting up flood gauges in low-lying areas to show how high the water could get during a hurricane, but pressure from real-estate agents got the signposts removed.

The feds bear some responsibility for the disaster-friendly design of Houston, too. Virtually all flood insurance in America is administered through the National Flood Insurance Program, which is supposed to prevent risky development by requiring better building standards and relocation of buildings that flood repeatedly. But since it was founded in 1968, the program has been contorted by developers, real-estate agents, and politicians lobbying for special treatment for their constituents. In places like Houston, the program helps enable development in high-risk areas by offering subsidized insurance rates that don't reflect the real cost of living in flood-prone areas, as well as by offering repeat payouts for often-flooded homes. Even before Harvey, the program was already $25 billion in debt.

As always, it's poor people and people of color who end up bearing most of the risk. "They not only have to deal with flooding in their homes, but pollution in water that's contaminated when water floods refineries and plants," Texas Southern University sociologist Robert Bullard told Huffington Post. "You're talking about a perfect storm of pollution, environmental racism, and health risks that are probably not going to be measured and assessed until decades later. The fact is that laissez-faire, unrestrained capitalism and lack of zoning mean people with money can put protections up, and people without can't."

In moments like this, it's always tempting to say that a disaster like Hurricane Harvey is a game-changer, that seeing the devastation and suffering this storm has wrought will help us think differently about the world we live in. In the past, big catastrophes have led to big changes. The fire on Ohio's Cuyahoga River in the 1960s resulted in the Clean Water Act; after the spill of the Exxon Valdez, Congress passed the Oil Pollution Act. In a rational world, Harvey would lead to (among other things) passage of carbon legislation to reduce emissions, as well as a fundamental restructuring of the National Flood Insurance Program to quit subsidizing development in risky places.

Instead, we are likely to get a lot of rah-rah about rebuilding Houston bigger and better than before, some marginal improvements in building codes, and a lot of fighting in Congress over how much money to spend on recovery. President Trump will tout the heroics of the rescuers and the TV ratings of the storm – he is his own empire of denial. He not only pulled the U.S. out of the Paris climate deal, but just weeks before Harvey hit, he rolled back common-sense requirements for flood protection in federal projects.

Beyond the post-storm platitudes, it's not hard to foresee what is coming. There will be another hurricane – next time it might hit Charleston or Miami or Norfolk, and it will destroy buildings and highways built in harm's way and it will again cause billions of dollars worth of damage. Eventually, taxpayers in Kansas will get tired of bailing out people who live on the coast, and disaster-relief funds will dry up. As seas rise, mortgage companies will stop writing 30-year loans for homes by the sea. Bond ratings for cities will fall. Coastal roads will be washed away. Airports will be flooded. And the great coastal retreat will begin.

The simple truth is, it's not just Houston that's done a poor job of thinking about the future – it's all of us. We've spent 40 years denying the risks of climate change, thinking that if we can just get everyone to buy a Prius and recycle their plastic, everything will be OK. The message of Hurricane Harvey is that it will not be OK. We're living in a new world now, and we better get ready. Mother Nature is coming for us. 

Leonardo DiCaprio, Sandra Bullock, Kevin Hart among the actors and artists leading the donations for Hurricane Harvey relief. Watch here.