To the Teacher
The three most devastating storms to hit the United States have all occurred within the past 12 years: Katrina in New Orleans in 2005, Sandy in New York and New Jersey in 2012, and now Harvey, which hit Houston at the end of August 2017. Although more lives were lost to Katrina, the economic costs of recovering from Harvey will probably be higher than those of Katrina or Sandy, and the economic impact for the nation as a whole is also likely to be greater.
While hurricanes are a fact of life in the Gulf of Mexico, a combination of factors contributed to Harvey’s destructiveness. The first set of factors is the result of climate change: rising temperatures and rising seas have exacerbated storms’ effects, leading to bigger storm surges and heavier rainfall. A second set of factors has to do with the Houston area’s rapid and unrestricted development. Developers have covered over wetlands and prairies that, in the past, had absorbed heavy rains.
This lesson includes an initial gathering to debrief what students already know and feel about the destruction caused by Harvey, followed by two readings intended to help students understand the human and natural context for Harvey’s devastation. Questions for discussion follow each reading. An extension activity has students research local climate change threats and consider how to address them.
Photo above: Houston, Aug. 27, 2017, by Texas Army National Guard Lt. Zachary West.
- What do you know about Hurricane Harvey?
- What images, stories, facts stand out most for you?
- How did you feel as you saw scenes from the hurricane in the media?
- Why do you think this hurricane was so damaging?
Reading 1: Hurricane Harvey’s deadly impact
Scientists had warned it was only a matter of time before a catastrophic storm would hit Houston. They predicted that the combination of rising seas, warmer temperatures, a lack of urban planning, and the city’s geography left this fourth–largest U.S. metropolis highly vulnerable to devastating flooding.
In August 2017, what scientists foretold came to pass. Hurricane Harvey poured a record–breaking 50 inches of rain on areas of Harris County, home to Houston. The storm killed dozens of people and damaged 100,000 homes. Texas Governor Greg Abbott predicted that the cost of rebuilding could be as high as $150 to $180 billion.
The storm’s impact is rippling far beyond Texas. The Houston ship channel is one of the world’s busiest shipping passages, and the Gulf region of Texas contributes nearly half of U.S. gasoline and petrochemical production. The storm damaged the oil refineries that line the shipping channel, causing average gasoline prices to rise nationwide just ahead of the Labor Day holiday. Harvey also knocked out half of the U.S. capacity for making ethylene, a basic ingredient in everything from phones and milk jugs to medical devices, shoes, and clothing.
Many oil and chemical companies have long refused to disclose details about the more dangerous materials stored in their plants. What is clear is that a lot of those plants seeped petroleum and chemicals into waterways during and after Harvey. Even before the worst of the storm had hit, the Coast Guard, which collects information about such leaks, had logged reports of 750 gallons of chemicals spilled into the Gulf of Mexico.
More dramatically, volatile chemicals at a plant operated by the Arkema company began to explode when the plant’s electric system and backup systems all failed and the company’s refrigeration system went down. The flooded areas also include 13 Superfund sites, places the federal government has designated as dangerously contaminated and in need of major cleanup. If will probably be months before scientists are able to evaluate the impact of the storm on these sites.
Major storms are nothing new for Houston. The city’s growth dates to 1900, when a category 4 hurricane demolished the nearby port city of Galveston, killing at least 6,000 people and convincing many survivors to relocate further inland to Houston. Hurricane Ike – until now the nation’s third costliest after Katrina and Superstorm Sandy – killed 74 people and caused $30 billion in damage before it shifted course away from Houston in 2008. Other lethal storms followed in 2001, 2015 and 2016.
Scientists say that the frequency and intensity of storms is rising because the climate is changing. "Climate change doesn’t cause extreme events," write Katharine Mach and Miyuko Hino of Stanford University in The New York Times. "It amplifies them."
As the earth’s average temperatures rise, both sea and air temperatures are hotter than in the past. Hurricanes typically lose force as they come closer to land. But the storms feed off hotter air and water, so instead of diminishing, Harvey’s wind speeds rose during the final 24 hours before it hit the coast.
At the same time, global sea level has risen eight inches since 1880, and water is rising much faster on the East Coast and the Gulf of Mexico. Add higher sea levels to faster wind speeds, and the upshot is storm surges that are higher and more powerful than those seen in the past.
Harvey’s unprecedented rainfall is also a result of a changing climate. Warmer air holds more water, and rainfall in the mid–latitudes is rising worldwide. While Harvey devastated Texas, monsoons on the other side of the world in India killed more than 1,000 people and displaced millions.
Climate change alone can increase rainfall 5 to 10 percent, and it can cause rainfall to increase by as much as 20 percent if ocean temperatures are higher than usual, according to Kevin Trenberth, a senior scientist at National Center for Atmospheric Research in Colorado.
No one knows exactly when or where the next monster storm will hit, but it’s clear that weather patterns are changing. "Unprecedented is increasingly the norm," write Mach and Hino.
- How much of the material in this reading was new to you, and how much was already familiar? Do you have any questions about what you read?
- What do you think will be the most difficult part of recovering from the storm, and why?
- Why do scientists say that climate change is making storms more powerful?
- How are higher temperatures and more extreme weather affecting your region?
Reading 2: Development and Devastation
Why wasn’t Houston better prepared for a foreseeable crisis? "We’re sitting ducks," is what Phil Bedient, engineering professor at Rice University in Houston, told reporters in March, 2016.
It didn’t have to be that way, Bedient told the New York Times after Harvey rained devastation on the Houston area. But high–speed growth in an area famous for flooding meant that all that water had nowhere to go.
Read this excerpt from a New York Times article by Richard Fausset, Manny Fernandez, entitled A Storm Forces Houston, the Limitless City, to Consider Its Limits (September 2, 2017).
Though its breakneck development culture and lax regulatory environment have been lauded for giving working people affordable housing — and thus a shot at the American dream — many experts and residents say that the developers’ encroachment into the wetlands and prairies that used to serve Houston as natural sponges has inevitably exacerbated the misery that the city is suffering today.
"There could have been ways to have more green space and more green infrastructure over the years, and it just didn’t work that way, because it was fast and furious," said Phil Bedient, a civil and environmental engineering professor at Rice University. Many developments were not built with enough open land or enough detention areas to take in floodwaters, Dr. Bedient said. "It’s been known for years how to do it," he said, "it just costs the developers more money to do it that way."
Greater Houston has always been a precarious place for a boomtown. It sprawls across a flat coastal plain, crisscrossed by slow–moving bayous, with clay soils that do not easily absorb water. The average annual rainfall is 48 inches.
The city grew rapidly in the postwar years, and in an effort to control storm water and direct the runoff to the Gulf of Mexico, two key bayous through the city were channelized — essentially converted to concrete culverts — while a third was widened, Dr. Bedient said. A network of channels — 1,500 of them, today totaling 2,500 miles — were built to move storm runoff out of neighborhoods and down to the sea.
But in the end, they may have provided a false sense of security. "And so the building just went rampant, and there weren’t many controls," Dr. Bedient said. "We had no zoning. It was like the Wild West, and you just built housing subdivision after housing subdivision up close to the bayous, up close to the channels."
By the 1980s, Dr. Bedient said, officials came to realize that the system could not handle big rainfalls: the green space that could have absorbed much of the water from a big storm was now paved over with parking lots, houses, churches and malls.
Metropolitan Houston has kept growing. Though the region suffered some tough years after the 1980s oil bust, Harris County, which includes Houston, experienced the highest annual population growth of any county in the United States in eight of the last nine years, according to census data.
Developers both responded to and fueled the boom, often doing what they wanted in Texas’ relatively laissez–faire regulatory climate. In 2015, the Houston Chronicle examined a sampling of permits issued to developers, and found that more than half the developers had failed to follow through on Army Corps of Engineers directives meant to mitigate the destruction of wetlands.
Two years ago, Erin Kinney, a research scientist with the nonprofit Houston Advanced Research Center, wrote that 65 square miles of freshwater wetlands had been lost in the Houston–Galveston Bay region, largely because of development and sinking land, and that 30 percent of Harris County was covered with impervious surfaces like roads, parking lots and roofs.
If the region begins to put stricter regulations on building, there is a chance that one of Houston’s great lures — affordable housing — may disappear. This is a concern for Joel Kotkin, the urban theorist and author who has been a great champion of Houston’s lax regulation policies.
"If you put the kind of super–strict planning shackles on Houston, that would be the way to kill it," he said. "Why would you live in a hot, humid, flat space if it was expensive?"
Like many others, he was quick to praise Houston’s energy and optimism, and said the city would recover. The Texas author Larry McMurtry, a former Houston resident, agreed.
"Houston will accept anybody who’s got hustle — it respects energy more than any place," he said. "Houston is a very resilient city, and it will overcome."
The Trump administration asked Congress for an initial $7.85 billion for recovery efforts in Houston, an amount that Texas Governor Greg Abbott called a "down payment" on the federal aid that will ultimately be needed.
In 2015, the Obama administration passed new rules requiring that developers who receive federal rebuilding dollars after a disaster must build in ways that take climate change into account (such as raising the elevation of buildings in flood–prone areas). But on August 15, 2017, President Trump reversed that measure, which he described as burdensome.
However, those burdensome rules might not only prevent future loss and heartache, but save money. According to a report by the Pew Charitable Trusts, every dollar invested in reducing the impact of disasters like Harvey saves $4 in relief and rebuilding costs.
- How much of the material in this reading was new to you, and how much was already familiar? Do you have any questions about what you read?
- How has unrestricted growth in the Houston area affected the severity of damage from hurricanes and other storms?
- Many people argue that a region benefits economically when homeowners and developers are allowed to build wherever they want. Should state and local governments restrict this kind of development? Why or why not?
- Do you think the federal government should require that rebuilding be done in ways that reduce Houston’s vulnerability to future storms? If so, what might those requirements be?
- How vulnerable are homes, farms, businesses, and wildlife in your area to climate–related disasters such as flooding, drought, wildfires, and heat waves? How prepared is your area to withstand these threats?
A. Research your community’s climate change threats
As homework, ask students to research this question:
What is the most urgent climate change–related threat facing your community? Cite three pieces of evidence to support your view that this is the most urgent threat.
The Union of Concerned Scientists website includes information about the range of climate change impacts that may be helpful. Also see information on the Alliance for Climate Education website about effects of climate change in different regions —— and ideas about actions students can take.
In the next class, have students present their ideas and arguments. Work with the group to come up with what you believe is the most urgent climate change–related threat in your area.
Next, break students into four small groups. Ask each group to research, in class or as homework, a different question related to the threat you have identified.
Group 1: What is the history of this threat in our community, and what can we learn from that history?
Group 2: What policy shortcomings (such as development and zoning policies, regulations, or environmental policies) may have contributed to the problem?
Group 3: What groups in your community are working on climate issues and on improving the resiliency of your community to climate change? What proposals have been put forward to address the threat?
Group 4: What have other cities, regions or nations done to address a similar threat to the one your community is facing? What can we learn from their experiences?
B. Take Action
Ask each group to present its findings, and facilitate a discussion to help the class decide on one or more needed reforms or actions your community should take to address the threat.
Help the class plan a project to raise awareness or press for action on the threat.