Research Science and Technology

On the front lines of the climate emergency

Climate scientist Katharine Mach is researching ways to adapt to our changing climate, including how people are being forced to retreat from areas becoming uninhabitable.
Katharine Mach is an Associate Professor at the University of Miami Rosenstiel School of Marine and Atmospheric Science and a faculty scholar at the UM Abess Center for Ecosystem Science and Policy.

Associate professor Katharine Mach’s research assesses climate change risks and response options to address increased flooding, extreme heat, wildfire, and other hazards. Photo: Evan Garcia/University of Miami

Hurricane Harvey dumped a year’s worth of rain on Houston in less than a week, causing bayous to jump their banks and unleashing so much flooding in neighborhoods that many residents had to abandon their homes by boat.

Some 8,000 miles away in Qatar, average temperatures have risen more than 2 degrees Celsius above preindustrial times, making the Arab nation one of the hottest places on Earth.

And in Bangkok, the Venice of Asia, temperatures not only continue to soar but the city is also sinking by up to 2 centimeters each year, putting its 10 million residents at risk.

Such are signs of a planet in peril—warnings issued by a burgeoning climate emergency that University of Miami scientist Katharine Mach says the world would do well to heed.

“In so many different ways, our current climate moment is one where climate change is happening, people realize it, and we’re seeing the impacts affecting our daily lives, whether it’s through flooding or increased incidents of extreme heat and drought,” said Mach, who joined the Rosenstiel School of Marine and Atmospheric Science in August as an associate professor of marine ecosystems and society.

“There’s recognition now that we’re behind the eight ball and not necessarily prepared to the degree we should be,” she said.

Mach is helping to change that.

Through her research, she not only assesses the risks posed by changing climatic conditions, she studies the way we are responding and adapting to those risks, whether it is through policy decisions and other measures like erecting seawalls and installing flood pumps.

One adaptation drawing scrutiny is managed retreat—moving people and property out of harm’s way of climate-related consequences such as sea level rise.

In a recent study published in the journal Science, Mach and other researchers write that the question is no longer whether some people will retreat from hazardous areas, but why, where, when, and how they will do so.

They note a dearth of research on the issue and how current practices of retreat mostly focus on the physical removal of people and assets, with little discussion given to the social, cultural, psychological, and long-term economic impacts of retreat.

Mach and her colleagues call for strategic retreat, arguing that “decision-making and planning should take place at larger geographic and temporal scales; involve multiple agencies and jurisdictions; address multiple hazards; and be integrated into planning for economic, social, and environmental goals.”

But it was another study, one for which Mach served as the lead investigator, that is garnering much more attention, raising concerns that areas that most need help in managing flood risk and adapting to the effects of climate change aren’t receiving it.

In that study, published in the journal Science Advances, Mach discovered that a government buyout program designed to help Americans move out of at-risk areas actually benefits more wealthy municipalities. Specifically, she and her team of researchers found that local governments are using FEMA funds to purchase flood-prone homes more often in affluent counties than in poorer ones.

“Not surprisingly, given that buyouts require enormous resources to administer, it has been higher-capacity locations as measured by income that have been more likely to get FEMA funding to do buyouts,” said Mach.

The study, which used FEMA data from more than 40,000 completed buyouts from 1989 through 2017, also found that once counties receive funding, they tend to use it to purchase and demolish homes in underserved areas. Possible explanations for that range from officials believing such municipalities face the greatest risk to regarding the buyout funds as an opportunity to do away with neighborhoods they deem undesirable.

Mach, who was most recently a senior research scientist at Stanford University and director of that institution’s Environment Assessment Facility, also has studied how a changing climate could foment violent armed conflict within nations.

She has been at ground zero on the climate change issue for much of her life, serving from 2010 to 2015 as co-director of scientific activities for Working Group II of the Intergovernmental Panel on Climate Change—work that culminated in the IPCC’s Fifth Assessment Report as well as its Special Report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation.

“That was an unreal opportunity being exposed to all of the science happening on the climate issue,” Mach recalled.

After that IPCC report was completed, she participated in the science-policy interactions that supported the negotiations of the Paris Agreement on climate change, answering questions, for example, on how a 1.5-degree Celsius temperature rise would impact small low-lying nations or countries that export fossil fuel.

A self-described tomboy as a youngster, Mach loved playing sports and exploring the outdoors while growing up in Northern California. But it wasn’t until she started studying science that she realized the outdoors she so adored are part of an environment that’s changing.

“I’m often asked if I get depressed about studying climate change,” she said. “The point at which I started to realize that the climate is changing is when I felt overwhelmed by the issue. But now, studying it has been empowering. It’s a motivating topic to investigate.”

She admires youths like Swedish environmental activist Greta Thurnberg for demanding action on climate change, saying younger people, more than older generations, will be most affected by climate change.

“There are [environmental] impacts that will continue to intensify over the whole course of their lifetimes,” explained Mach.

She is a Harvard graduate, having left her home in San Mateo, California, for the Cambridge-based Ivy League with just one suitcase in tow, launching herself, she said, into a “very different and somewhat intimidating world.”

It ended up “going okay,” she said with a measure of modesty that belies her stellar achievements as an undergraduate.

Mach, who will present her research at the University of Miami’s scheduled Miami Climate Symposium in January, graduated summa cum laude with a degree in biology from Harvard. She spent her undergraduate summers conducting research at Shoals Marine Laboratory on Appledore Island off the coast of Maine, where, she jokingly recalled, the islet’s thousands of seagulls kept her company.

The highlight of Mach’s undergraduate years, though, came during her senior year, when her younger brother enrolled at the university. “So I had a little bit of family at school,” she said.

She went on to earn a Ph.D. from Stanford University. In addition to her Rosenstiel School appointment, she also serves as faculty scholar at UM’s Abess Center for Ecosystem Science and Policy.

Mach is as passionate about the importance of increasing the number of women, ethnic minorities, and people with disabilities who are represented in the sciences as she is about the pressing need to address the impacts of climate change.

Members of the National Academy of Sciences and Nobel laureates in chemistry, physics, and physiology or medicine, she said, are not a reflection of the nation’s growing racial and ethnic makeup, instead representing a very narrow demographic.

“And I think that’s a problem,” said Mach. “We’re not as a society going to be as well off if science is by and often for a subset of America as a whole.”

She is alarmed that the Trump administration has announced its plans to officially withdraw next fall from the Paris climate accord.

“The United States is the largest emitter of greenhouse gases, historically,” said Mach. “Does taking action against climate change harm Americans? Absolutely not. What we have seen is that building a cleaner energy system and having land-use patterns that don’t put as much heat-trapping gas into the atmosphere can strongly be to the benefit of all Americans, economically and environmentally and also in terms of our health. If the U.S. doesn’t act, the world is not going to solve this problem.”