Elevated Death Rates Linked to Hurricanes Persist for 15 Years After Storms
According to new research published in Nature, hurricanes and tropical storms in the United States are linked to higher death rates for 15 years after a storm hits.
"In any given month, people are dying earlier than they would have if the storm hadn't hit their community," said senior study author Solomon Hsiang, a professor of environmental social sciences at the Stanford Doerr School of Sustainability. "A big storm will hit, and there's all these cascades of effects where cities are rebuilding or households are displaced or social networks are broken. These cascades have serious consequences for public health."
Indeed, official government statistics only account for the number of people killed during these extreme weather events. Those who die typically do as a result of drowning or some other type of trauma. However, the new analysis shows that the average U.S. tropical cyclone indirectly causes 7,000 to 11,000 excess deaths. In fact, Hsiang and lead study author Rachel Young estimate there have been between 3.6 million and 5.2 million deaths in the U.S. due to tropical storms since 1930. This exceeds the total number of deaths from motor vehicle accidents, infectious diseases, or combat fatalities in wars across the country during the same timeframe. According to official government figures, the death toll from these storms stands at approximately 10,000 people.
The new estimates are derived from a statistical analysis of data on 501 tropical cyclones that impacted the Atlantic and Gulf coasts between 1930 and 2015, along with mortality rates for different populations in each state before and after each cyclone. The researchers built on concepts from a 2014 study by Hsiang, which showed that tropical cyclones hinder economic growth for 15 years, and a 2018 Harvard study, which found that Hurricane Maria caused nearly 5,000 deaths in the three months following the storm in Puerto Rico—almost 70 times the official government figure.
Young and Hsiang’s study is the first to highlight hurricanes as a significant factor influencing the nationwide distribution of mortality risk. While the research reveals that over 3% of deaths across the country are linked to tropical cyclones, the impact is disproportionately severe for certain populations. Black individuals, for example, are three times more likely to die after a hurricane than their white counterparts. This statistic gives hard evidence to concerns long expressed by Black communities about the unequal treatment and challenges they face after natural disasters.
The researchers estimate that tropical cyclones contribute to 25% of infant deaths and 15% of deaths among people aged 1 to 44 in the U.S. For these demographics, Young and Hsiang note that the increased risk from hurricanes significantly affects overall mortality, as these groups typically have low baseline death rates.
Hsiang's Global Policy Laboratory at Stanford is currently investigating the reasons tropical storms and hurricanes lead to deaths over a span of 15 years. The lab combines economics, data science, and social sciences to address critical policy issues related to managing global resources, often focusing on the effects of climate change.
In examining the mortality risk from hurricanes, the challenge lies in untangling the intricate series of events that follow a storm and eventually impact human health, then assessing potential interventions.
These events can be so distanced from the initial disaster that even those directly affected may not realize the connection. For instance, Hsiang and Young explain that people may use their retirement savings to repair storm damage, diminishing their ability to afford future healthcare. Family members might relocate, disrupting essential support systems that play a key role in maintaining long-term health. Additionally, public funds may be redirected toward immediate recovery efforts, diverting resources from investments that could otherwise improve health outcomes in the future.
