This week’s On The Radio segment discusses how climate change is making storms like Harvey more likely.
Transcript: Over 51 inches of rain fell in the Houston area last month during Hurricane Harvey, setting a record for the continental U.S., and scientists say a changing climate added to the deluge.
This is the Iowa Environmental Focus.
The Clausius-Clapeyron equation, a law of thermodynamics, says that the warmer a body of air is, the more moisture it can hold. Sea surface temperatures near where Harvey picked up its strength were about 1 degree Celsius higher than average, making the air above it warmer too. In this case, the atmosphere surrounding Hurricane Harvey was able to hold roughly three to five percent more moisture than usual.
In addition, sea levels have risen by about six inches in the last few decades due to global warming. Even minimal sea level rise can lead to a large increase in damages to structures on land during a flood.
While climate change did not cause Hurricane Harvey directly, scientists say it will likely make category four storms like it more frequent in the future.
While the downpour in Houston has finally subsided, the Texas city has few options for draining the 15 trillion gallons of water that fell in the region.
The city of Houston has no levees or pumps or flood walls it can call on to drain water more quickly back into surrounding bayous. As a low-lying coastal plain, it also has a rather flat landscape. Arturo Leon, a professor of water resources engineering at the University of Houston said, “This means the capacity for drainage is very slow. If there were a slope, then it would drain faster,” in a report by Scientific American.
In the last thirty years, the city has grown a great deal, all without any zoning laws that regulate development, even in flood prone areas. For example, since 2010 about 7,000 residential buildings have been built on land the federal government considers a 100 year floodplain, according to a review by the Washington Post. Stormwater drainage systems have not kept pace with the area’s development.
Sam Brody, director of the Center for Texas Beaches and Shores at Texas A&M University, said, “Houston is the Wild West of development, so any mention of regulation creates a hostile reaction from people who see that as an infringement on property rights and a deterrent to economic growth. The stormwater system has never been designed for anything much stronger than a heavy afternoon thunderstorm.”
As a result, the city relies heavily on surround bayous to reabsorb rainwater. Bayous are slow moving, and especially so on Houston’s flat landscape.
A list of options for donating to victims and displaced residents in the area can be found here.
To begin, sea surface temperatures near where Harvey picked up its strength were about 1 degree Celsius higher than average. The Clausius-Clapeyron equation, a law of thermodynamics, says that the warmer a body of air is, the more moisture it can hold. In this case, the atmosphere surrounding Hurricane Harvey was able to hold roughly three to five percent more moisture than usual.
“The water in the Gulf of Mexico is the heat reservoir to support these hurricanes,” said Ben Kirtman, an atmospheric scientist at the University of Miami, in a report from NPR. Kirtman added, “For a small change in temperature, you get a huge amount of evaporation.”
In the last three decades, sea levels have risen worldwide by about six inches thanks to a warming climate and, in part, to human activities like offshore oil drilling. Higher sea levels make inland floods more devastating.
Climate Central scientist Ben Strauss said, “Every storm surge today reaches higher because it starts from a higher level, because sea level is higher. A small amount of sea-level rise can lead to an unexpectedly large increase in damages to most kinds of structures.”
Scientists are careful to point out that climate change did not directly cause Harvey, but is likely to produce storms like it more often. A recent report from the National Academy of Sciences, Engineering and Medicine revealed that category 4 hurricanes like Harvey will occur more frequently in the future due to a warming climate.
A recent study by the Pew Charitable Trusts generated flood risk scores for 84,123 primary and secondary schools nationwide.
The report’s authors pointed out that flooding is the most costly and common natural disaster, affecting every region of the U.S. Many times, severe floods badly damage schools, causing them to close. For example, the study points out, floods in West Virginia in June 2016 cost $130 million in damage to regional schools.
Researchers used three metrics to generate county-wide composite flood risk vulnerability scores for schools in all fifty states including: a school’s location within a designated flood zone, the percentage of a school’s neighborhood (as represented by ZIP code) located within a flood zone, and the number of historical flood-related federal disaster declarations in that county.
Among the study’s major findings are that flood risk is distributed across diverse regions of the country. Schools with the highest flood risk scores were located in the Atlantic Coast, Gulf Coast, Mississippi River corridor, and southwestern Arizona. Similarly, those schools with the highest composite flood risk scores were located in both coastal and inland regions. Those 100 counties with the highest composite flood risk scores include 6,444 schools that serve almost 4 million students.
The study made some recommendations for steps policymakers can take to increase flood resiliency for schools. They included generating up-to-date local flood maps, developing pre-disaster flood plans for schools, working to leverage federal assistance, and relocating schools out of floodplains if possible.
The Pew Charitable Trusts full analysis can be found here.
In episode 7 of EnvIowa, we sit down with Dr. Larry Weber to learn more about the Iowa Watershed Approach. Dr. Weber is a UI professor of Civil and Environmental Engineering and Director of IIHR–Hydroscience and Engineering, which is the parent organization of the Iowa Flood Center.
Dr. Weber explains how the $96.9 million project came to be and how it improves quality of life for Iowans while protecting our natural resources and health. He tells of successes the Iowa Flood Center has had with its flood reduction and water quality improvement programs and discusses the organization’s fight to maintain state-funding earlier this year.
The director and his team work many long days and spend hours each week driving around the state to each of the nine watersheds included in the Iowa Watershed Approach. For Dr. Weber, his work’s motivation is clear. He said,
“As an Iowan, I grew up here, I’ve worked and spent my whole career here, and I plan to retire here. I want a livable state in which we can enjoy our water and natural resources, enjoy being in the outdoors, enjoy interacting with the rivers, lakes and streams of Iowa, and, you know, programs like the Iowa Watershed Approach, I think, are vital to the long-term sustainability of our resources in Iowa.”
The EnvIowa podcast is also available on iTunes and Soundcloud, a complete archive of EnvIowa episodes can be found here.
The Iowa legislature has amended its 2018 budget proposal to restore $1.2 million in funding to the Iowa Flood Center.
The 2018 fiscal year budget plan was released earlier this week. The education spending bill proposed by Republicans included $20 million in cuts and originally featured a $1.5 million decrease in funding for the flood center. Wednesday evening the House Appropriations committee reinstated 2018 funding for the flood center by transferring $950,000 out of general appropriations to the University of Iowa and another $250,000 from a National Guard educational assistance program.
Representative Ashley Hinson, a Republican from Marion, worked as a news anchor, reporter and producer for KCRG-TV9 in Cedar Rapids during the 2008 floods. He said, “I do know the value of the Flood Center to Cedar Rapids and Linn County, and immediately started having those conversations about its importance to our area specifically with our budget chairs and other appropriations committee members.”
“The solution we found was based on trying to balance our priorities with a tough budget year,” responded Hinson. He added, “It was also my understanding that the Flood Center was a ‘priority’ for the University of Iowa, which is why we felt it appropriate to essentially have them share in funding it. I’m happy we were able to find a solution within our current budget constraints.”
The report, titled “Medical Alert! Climate Change is Impacting our Health” was written by medical doctors, including allergists, pediatricians, infectious-disease doctors, OB/GYNs and gerontologists from eleven health organizations.
Very few Americans, less than 32 percent, can name a specific way in which climate change harms human health. “Doctors in every part of our country see that climate change is making Americans sicker,” said Dr. Mona Sarfaty, the director of the new consortium.
The authors broke down the specific health effects of climate change in each region of the U.S. The doctors explain that three by-products of climate change will directly impact human health: air pollution, extreme heat and extreme weather events. Increased temperatures associated with climate change intensify smog, wildfires and pollen production, leading to poor air quality, the report said. “Poor air quality increases asthma and allergy attacks, and can lead to other illnesses, hospitalizations, and deaths,” the authors wrote.
Rising global temperatures cause more frequent, longer, and more extreme heat waves in many parts of the U.S. Excessive heat leads to heat-related illness, exacerbates some medical conditions, and can cause death due to heat-stroke and dehydration. The report read, “Anyone can be harmed by extreme heat, but some people face greater risk. For example, outdoor workers, student athletes, city dwellers, and people who lack air conditioning (or who lose it during an extended power outage) face greater risk because they are more exposed to extreme heat.”
The physicians pointed out that extreme weather events are also taking a toll on their patients. The increased frequency and severity of major storms, floods, and droughts can cause injury, displacement and death, the report read. These events often prevent residents from receiving proper medical care due to blocked roads, destroyed bridges and the like. Gastrointestinal illness and disease often follow the power outages associated with extreme weather events as well, according to the doctors.
Beyond these direct impacts, climate change also speeds up the spread of infectious diseases and has an insidious impact on humans’ mental health. With temperatures rising around the world, infectious disease vectors like ticks, mosquitoes and fleas can now survive in regions that were previously too cold for them. For example, “Ticks that carry Lyme disease have become more numerous in many areas and have expanded their range northward and westward,” the report said.
U.S. residents that have experienced increasingly common extreme weather events like foods, major storms, and droughts are likely to suffer mental health consequences including post-traumatic stress disorder (PTSD), depression, and anxiety. Anyone could experience these effects, but women, pregnant women, the elderly, children, and those with a preexisting mental health condition are most at risk.
The report concluded with a call to government leaders, asking them to address climate change in the name of human health. It read, “Doctors agree with climate scientists: the sooner we take action, the more harm we can prevent, and the more we can protect the health of all Americans.”