Home Science Energy As Harvey rains down devastation, Houston stands together.

As Harvey rains down devastation, Houston stands together.

Downgraded from a hurricane to a tropical storm, Harvey continues to rain rivers down on Houston and its surroundings, inundating homes and businesses and tearing apart the lives of tens of thousands of people. It is hard not to be moved by the pictures and videos of police officers and ordinary citizens in boats and inflatable rafts rescuing people from roofs and partly submerged cars, volunteering at shelters and handing out food and water to the hungry. And while the local, state and federal response appears to be going about as well as could have been expected, Harvey has already left a devastating mark on the nation’s fourth-largest city and will surely etch itself in the pantheon of great natural disasters alongside storms like Katrina and Andrew.

Grueling days lie ahead. The storm has dropped more than 30 inches of rain in some areas, with more expected, and even when the waters recede, many lives will not return to their normal rhythms for months or years, if ever, as displaced families make their way back home, take stock and begin arduous cleanups. Homes, businesses and other structures will be beyond repair, forcing residents and government officials to make difficult decisions about whether to rebuild and how. The oil and gas industry concentrated on the Texas coast could be disrupted for weeks or longer, sending ripples across energy markets and the economy.

There are lessons to be learned, as there always are after disasters like this. Some of those lessons — like how unchecked urban sprawl and paving over of wetlands and prairies have increased the risk posed by floods in Houston and other cities — were evident long before Harvey and ought to become more urgent in the storm’s wake. Experts will also point out, as they have before, that cities ought to abandon traditional flood-control approaches that were never very good and are wholly inadequate for dealing with the kinds of intense storms that have become more frequent in recent years. Instead, they need to adopt smarter strategies that provide more space for floodwaters to seep into the ground and drain away slowly without leaving behind a trail of destruction.

There may also be a message here for President Trump. Although it’s expecting a lot of someone who calls global warming a hoax, he might pause to reflect on the possible connections between climate change and extreme weather events like this one. Climate scientists resist drawing a link between climate change and any particular event. But warming can make a bad situation worse. Rising temperatures warm the oceans, causing more evaporation, more moisture in the atmosphere and heavier rainfall. Warmer oceans also provide added fuel for storms like Harvey, making them bigger and more intense.

Mr. Trump might also rethink his war on environmental safeguards. Just two weeks ago he reversed an Obama-era policy that sought to prevent federal funds from being used to build infrastructure projects in flood-prone areas.

To do right by the people in Texas, Congress should do more than simply cut a check for relief funds when it returns to work next week. The National Flood Insurance Program, for instance, is badly in need of reforms that encourage local governments and developers to adopt better building standards and reduce flood risks, not just in Texas but in Louisiana and other flood-prone states.

The program is unsustainable as it exists today; it owes the Treasury nearly $25 billion, money it used to pay claims for previous disasters.

When calamity strikes, this country always seems to be looking in the rearview mirror, lamenting its failure to heed long-ago warnings. As Houstonians pick up the pieces, as they will, politicians and planners need to look ahead, to find ways to build more resilient cities and coastlines.