Many climate change experts have weighed in on how an overabundance of greenhouse gases in the atmosphere are making normal weather patterns more extreme and thus worse for the people experiencing them. No matter how heartening the photos and stories in Houston of people helping and rescuing each other, we’re still left with the overwhelming destruction of the storm. The dotted lines between climate change and catastrophic weather are getting more solid every day.

What made Harvey so catastrophic, besides the 50 inches of rain, and why was there so much of it?

Warmer water. The waters of the Gulf of Mexico are unusually warm this summer—between two and three degrees above normal—which gave Harvey extra energy and moisture. As Holthaus wrote:

Climate change is making rainstorms everywhere worse, but particularly on the Gulf Coast. Since the 1950s, Houston has seen a 167 percent increase in the frequency of the most intense downpours. Climate scientist Kevin Trenberth thinks that as much as 30 percent of the rainfall from Harvey is attributable to human-caused global warming. That means Harvey is a storm decades in the making. ... A warmer atmosphere enhances evaporation rates and increases the carrying capacity of rainstorms. Harvey drew its energy from a warmer-than-usual Gulf of Mexico, which will only grow warmer in the decades to come. At its peak, on Saturday night, Harvey produced rainfall rates exceeding six inches per hour in Houston, and its multiday rainfall total is close to the theoretical maximum expected for anywhere in the United States.

A stalled jet stream. As climatologist Michael Mann (his writing is being reported in many places, and it’s all a must-read) told Think Progress: “The kind of stalled weather pattern that is drenching Houston is precisely the sort of pattern we expect because of climate change.” Even after it was downgraded to a tropical storm and finally a tropical depression, Harvey just hovered over the Houston area, dumping more and more rain.

This conclusion is nothing new. A 2012 study by the National Oceanic and Atmospheric Administration, co-written by climate scientist Jennifer Francis, a leading expert on how global warming and the related Arctic amplification affect the jet stream and extreme weather, explained it further.

“Enhanced warming of the Arctic affects the jet stream by slowing its west-to-east winds and by promoting larger north-south meanders in the flow,” NOAA said. “The researchers say that with more solar energy going into the Arctic Ocean because of lost ice, there is reason to expect more extreme weather events, such as heavy snowfall, heat waves, and flooding in North America and Europe but these will vary in location, intensity, and timescales.”

Even beyond climate change, there have been so, so many other factors that made this situation—and could make future situations—worse:

Regulatory flood protections gone. Just days before Harvey hit, Donald Trump signed an executive order that abolished many flood protections established by President Obama. Trump, pretending that he cares about the country’s infrastructure, got rid of the regulations that put a curb on building roads, bridges, and other infrastructure in areas that are susceptible to flooding. Although that executive order didn’t affect anything—yet—it means that construction projects can go full throttle on land that shouldn’t be built on. This “will lead to more costly and damaging consequences of these floods," said Rachel Cleetus of the Union of Concerned Scientists, in a story in The Independent.

Trump rescinded an Obama executive order requiring builders who receive federal funds for a project to account for the risk of flooding in their construction plans. Trump called it “job-killing.” How many people in Houston are going to work right now? asks Eugene Robinson of The Washington Post.

Overdevelopment and deregulation run amok. Houston has grown into the nation’s fourth-largest city and sprawls across Harris County, an area of nearly 1,800 square miles with a population of 4.5 million. Much of the area’s most recent development, devoid of any zoning rules, has been built on what always was swampland. What should have still been land to absorb rainfall and buffer the developed areas is now concrete. According to a story in The Washington Post:

As the country’s fourth-largest city expanded, replacing prairie with impermeable surfaces such as pavement and concrete, the land was rendered less and less capable of absorbing floodwater. Without proper adaptive measures, this made an already flood-prone place more vulnerable. A ProPublica and Texas Tribune investigation found last year that those who have overseen Houston’s flooding issues discounted scientists’ warnings as “anti-development.” In the coming months and years, the city may pay a high price for such shortsightedness.

Looming public health crises. Public health experts warn that flooding of this size, especially in an urban area, carry a multitude of health risks. Floodwaters are likely to be mixed with sewage and animal waste, increasing the risk of E. coli exposure. Direct contact with floodwater (as if residents had any choice) can cause skin infections. People forced to go without medical treatment, especially dialysis and cancer patients, face serious health setbacks. Temperatures have headed back into the 90s, and with so much standing water, there will be an upsurge in the mosquito population. In other words, it’s not just colonies of floating fire ants, as frightening as those look.

Toxic chemical exposure disasters. The Arkema chemical plant in nearby Crosby, Texas, 20 miles northeast of downtown Houston, has now exploded, sending toxic fumes into the air and sending some people to area hospitals, at least as a precaution. The French firm Arkema says it has no choice but to let the fire burn itself out. Floodwaters in an area with so many oil refineries (at least one gas spill has been reported) carry the risk of exposure to a boatload of harmful chemicals. The Sierra Club has issued a list of other potential disasters-in-waiting, including problems at 10 Houston-area chemical facilities and oil and gas refineries. The Washington Post reported that the floods threaten to turn Houston’s Environmental Protection Agency Superfund sites into a “toxic soup.” You think Superfund site cleanup is going to be high on EPA Administrator Scott Pruitt’s agenda?

Economic downturn and a whopping rebuild expense. Climate change is already having an effect on local economies, and it hits the poorest residents the hardest. A study in Science magazine broke down the effect of warming temperatures, county by county, in the U.S. It shouldn’t be any surprise that the areas most affected are in the Southeastern U.S., with some counties in Arizona and New Mexico thrown in. “Not surprisingly, Atlantic coastal communities are projected to take a toll from rising seas and strengthening hurricanes,” said a report on the study.

Harvey is already predicted to be the most expensive natural disaster in U.S. history, with a potential price tag of $160 billion. According to a story in USA Today:

“Parts of Houston, the United States' fourth largest city, will be uninhabitable for weeks and possibly months due to water damage, mold, disease-ridden water and all that will follow this 1,000-year flood,” said AccuWeather president Joel Myers. The Federal Reserve, major banks, insurance companies and other business leaders should begin to factor in the negative impact this catastrophe will have on business, corporate earnings and employment, Myers said.

Right now, the face that 35,000 people are homeless is more concerning than corporate earnings. But perhaps an economic downturn is the only problem Republicans think is worth addressing.

Meteorologist Holthaus offers some thoughts on what to do about the new weather reality:

Adapting to a future in which a millennium-scale flood can wipe out a major city is much harder than preventing that flood in the first place. By and large, the built world we have right now wasn’t constructed with climate change in mind. By continuing to pretend that we can engineer our way out of the worsening flooding problem with bigger dams, more levees and higher-powered pumping equipment, we’re fooling ourselves into a more dangerous future. It’s possible to imagine something else: a hopeful future that diverges from climate dystopia and embraces the scenario in which our culture inevitably shifts toward building cities that work with the storms that are coming, instead of Sisyphean efforts to hold them back. That will require abandoning buildings and concepts we currently hold dear, but we’ll be rewarded with a safer, richer, more enduring world in the end. … The symbolism of the worst flooding disaster in U.S. history hitting the sprawled-out capital city of America’s oil industry is likely not lost on many. Institutionalized climate denial in our political system and climate denial by inaction by the rest of us have real consequences. They look like Houston. Once Harvey’s floodwaters recede, the process will begin to imagine a New Houston, and that city will inevitably endure future mega-rainstorms as the world warms. The rebuilding process provides an opportunity to chart a new path. The choice isn’t between left and right, or denier and believer. The choice is between success and failure.

And as awful as Harvey as been for Southeast Texas, and now Louisiana, we need to remember that extreme weather events are happening elsewhere in the world, too. The worst monsoon in years (some estimates were 10 times the normal amount of rain) caused catastrophic flooding in South Asia and killed 1,200 people in India, Nepal, and Bangladesh, and displaced millions. Mumbai, home to more than 20 million people, is awash with floods, including its financial district. Nearby Indian states also are flooded, and huge numbers of farms have lost crops. "This year farming has collapsed due to floods and we will witness a sharp rise in unemployment," said Anirudh Kumar, a disaster management official in the Indian state of Bihar, whose citizens often migrate to cities in search of jobs, according to a story in The Telegraph. At the same time, in Niger, at least 44 people died and hundreds of homes were lost because of heavier-than-usual rains during the rainy season.

“Couldn't you hear what the scientists were saying?” asks former Vice President Al Gore in An Inconvenient Sequel: Truth to Power. “Couldn't you hear what Mother Nature was screaming at you?”

It’s high time more people started listening.