Across America, the stereotypically lazy, hazy days of summer have turned considerably more serious. Dangerous heat waves fueled by a warming planet are increasing cases of heat stroke, killing important crops, generating stronger summer storms and knocking out electricity. 

An analysis of government data by The Associated Press reveals that power outages from severe weather have nearly doubled in the past two decades.

When Joan Casey of Columbia University’s Mailman School of Public Health dove into the scientific research eight years ago to better understand the impact these outages were having on public health, there wasn’t much data—and what there was came from Superstorm Sandy in 2012. 

Sandy slammed into the northeastern United States that October and the power went out in lower Manhattan for days.

“There were these rolling blackouts. Clinicians in emergency departments were reporting that they saw more people than average, or more people requesting to power medical devices than they would have expected,” Casey said of her scientific review. “But there was nothing systematic or comprehensive in any way.” 

Now, Casey and her team of 10 multi-disciplinary researchers across the United States are among the first researchers taking a comprehensive look at how power outages affect public health. They have also begun studying the negative health impacts of wildfires, including an intriguing possibility that wildfire smoke could hasten the onset of dementia.

Casey and company are part of a growing new field: climate epidemiology. “At a basic level, climate epidemiology is understanding how our climate and the changes it brought on by man-made decisions are affecting our collective health,” said Casey. 

This work is coming at a crucial time. According to the World Health Organization, climate change is expected to cause about 250,000 additional deaths per year between 2030 and 2050.

Casey, 36, an avid runner who competed in track and field for Cornell University, was first drawn to studying power outages in 2014, after completing her postdoctoral studies at the University of California, Berkeley. There, she experienced the state’s planned public utility shut downs during periods of high wildfire risk. “There was one time where we didn’t have power for about three days. For us, it was mostly an inconvenience. But if you think about someone with sleep apnea that uses a machine with sleep, it can be quite dangerous,” said Casey.

A prolonged power outage—loosely defined as eight hours or more—can be deadly for those who rely on oxygen tanks to breathe, need electricity to charge medical implant devices, or take medication that must be refrigerated. Electricity outages can also increase the risk of carbon monoxide poisoning from the improper use of generators. 

Casey and her team are now studying the data of reported outages between 2008 and 2020 in 95 percent of counties in the United States. It has revealed specific areas that appear to have a disproportionate number of power outages: parts of Michigan, Maine, the Appalachian states, and some regions of California. “We got this very messy data set that some graduate students here at Columbia have worked really hard to get into usable shape. But the end result of that is millions and millions of rows of data that we know how to work with,” said Casey.

The next step for these eagle-eyed data experts is comparing power losses with two more factors: the Centers for Disease Control and Prevention’s Social Vulnerability Index—the 15 variables that identify populations in need of extra help during a natural disaster—and Medicare records of adults over 65 who use electronic medical devices. 

“We are actually able to look at the overlap of medical device use and power outages. Unfortunately, what we’re seeing is a trend where places that have more people using medical devices that require electricity have more power outages. So, that’s not great,” said Casey.

Eventually, the team will use the data sets to create a three-layered (region, reported power outages and number of residents who use an electronic medical device) digital map of targeted areas where residents face the greatest risk during a prolonged power outage to better help the most vulnerable when the lights go out.

Long before the advent of climate epidemiology, a watershed moment of understanding the serious impacts that the environment can have on health occurred in 1948, when a thick, yellow-hued layer of smog and haze blanketed parts of the Northeast and Midwest. The city of Donora in the southwest corner of Pennsylvania bore the brunt of the smog, with 20 casualties linked to what would become the largest air pollution disaster in American history. The smog was created by multiple steel mills and zinc works built in the area. The same places that kept the town employed was poisoning them. 

A survey of the disaster was convened shortly after, with mixed results. According to historian Lynne Page Snyder, “The federal survey of Donora marked a new area for federal policy. It articulated a shift from program emphasis on source-based research to a focus on health effects research as a basis for policy making.” American Steel and Wire settled the lawsuits following the smog without accepting any blame for the event. However, it shifted interest towards a new kind of public health and President Truman did convene the first national air pollution conference in 1950.

In the 21st Century, the smoke created from increasingly potentially record-breaking fire seasons is creating similar dangers to the smog from factories. 

“One really interesting thing about wildfires is the composition of the smoke. One wildfire does not produce the same types of exposure as another. If homes are burning or a lot of plastic, could it be worse for health potentially than burning a forest of trees? Or does the type of tree that’s burning matter? There’s endless questions there,” said Casey.

The work she and her team are now doing on the negative health impacts of wildfires focuses on adults over 65. They’re examining a wide range of problems, including the emotional trauma of losing neighbors and loved ones, the physical and mental stress from evacuation or home loss, and the effects of repeated exposure to smoke.

Notably, the team is searching for the possible connection between wildfire smoke and the onset of dementia. “Wildfires produce large quantities of particulate matter that we can inhale. Some of it is in really fine particles, called ultra fine particles. These can actually cross the blood brain barriers and potentially cause actual physical changes in the brain,” Casey explained. 

She is partnering with Kaiser Permanente in southern California to study electronic anonymized health records from the region’s hospitals, wildfire reports and a major survey from the University of Michigan called the Health and Retirement Study. “We can use de-identified data from Kaiser track where people over 65 live, their demographic characteristics, and link where they live to these wildfire exposures,” said Casey. 

This data is cross-referenced with a model created by Casey’s collaborators at the University of California, San Diego that measures the level of wildfire particulate matter in the area, to look for any patterns between the ultra fine particles and dementia diagnosis.

If the study concludes that adults over 65 exposed to wildfires are at a higher risk of developing dementia, better protections and precautions for those living in wildfire prone areas can be implemented. These range from smaller personal decisions like wearing an N95 mask even while inside if a wildfire is nearby, to much larger social implications like working alongside the National Center for Disaster Preparedness or Red Cross to create better planning protections or relocation incentives for those living in fire danger. 

Regardless of the results of Casey’s study, the time to better protect people from increasingly long and dangerous fire seasons and other air pollution is now. “We can give individuals masks, but we need to think about broader scale change to protect people,” said Casey.

Laura Baisas is a freelance science journalist and writer from New York, by way of the Jersey Shore. She spent almost a decade at NBC News as a producer and writer. Laura is also an open-water marathon swimmer and has competed in multiple long distance events, including swimming around Manhattan (28.5 miles). She has a master’s degree from Columbia University Graduate School of Journalism and is a graduate of Marquette University.