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Double Trouble: The Importance of Thinking About Compound Risk

A giant sandstorm pummels northern South Sudan
A haboob,  a fierce summer wind that carries sand from a desert, pummels northern South Sudan. Compound risk, such as a drought combined with a sandstorm can devastate the area’s farming  Photo: Dale Willman

As any parent can attest, life is not without risk. When our children are young, we worry about coughs, sniffles and infections. If they grow into athletes, we worry about injuries. Risk — in simple terms, the likelihood of something bad happening — is always with us.

Many of these threats are localized to ourselves, our families, our extended circles. Will I lose my job? Did my friend just have a car accident? Issues such as these are concerning. But if something is happening to someone else, or in what is perceived to be the distant future — say, climate change — scientists tell us we’re more likely to discount its effects.

It’s also difficult to wrap our heads around the possibility that multiple disasters could happen simultaneously. We often tend to think of risk as something unique and in isolation from other events, something we can address one at a time. But life is complex, and so can be risk.

Compound risk — when multiple risks occur simultaneously, or one after another — was the topic of a recent discussion as part of the Resilience Media Project, which is a part of the larger Initiative on Communication and Sustainability at Columbia University’s Earth Institute.

Radley Horton is a Lamont Associate Research Professor and climate scientist at Columbia University. He says people have a particular blind spot when it comes to compound risk. “It’s maybe relatively easy for an individual … [who is] thinking about climate and adaptation to envision a single event such as a heat wave and what its impacts might be. But it’s much tougher to think about things like, well, what if the heat wave includes both heat and humidity? Or what if that heat wave happens right after a hurricane has knocked the power out?” Or, how do you protect people from a hurricane during a pandemic?

These compound risks can be especially dangerous to human systems designed to keep us alive. For instance, the way we get our food. Right now, more than a third of the United States is facing a moderate drought, or worse, including a number of states that grow the majority of the nation’s grain. If those states are then hit by a sustained heat wave, the results could be catastrophic, especially if that heat is accompanied by yet another disaster.

Food issues can also become much more widespread because of compound risks, says Horton. For example, the jet stream in the summer could shift to set up a high-pressure ridge that simultaneously affects major agricultural lands around the world. “So, you might have a ridge over the U.S, corn belt. You might have another ridge over the breadbaskets of the Ukraine. You might have another ridge over East Asia.” Such a scenario could lead to rapidly drying lands. “The absence of rain, the absence of cloud, the absence of strong sort of mixing winds and cool air from the north can lead to flash drought in some regions.” And that could cause worldwide disruption to food supplies.

A woman kayaking along the Osgood River in Adirondack Park, New York
Compound risk can occur close to home. Waterways in the Adirondack Park of upstate New York were damaged by acid rain over the last 50 years. While some waterways have partially recovered, increasing temperatures brought on by climate change could do further damage Photo: Dale Willman

Discussion around compound risk has increased in recent months because of the current pandemic. If the coronavirus has shown us anything, it’s that the systems upon which we depend are often fragile and vulnerable to disruption. Our economic system is in crisis mode, with high unemployment and lowered consumer spending. Our health care system in particular has been severely stressed by the virus, with many intensive-care units struggling to handle the rush of cases. With wildfire and hurricane seasons also now upon us, it takes little imagination to see what could happen when we are affected by more than one risk.

A great place to start learning about compound risk is by watching our webinar. Journalists can also find additional resources linked below, as well as possible entry points for reporting on compound risk.

One of the priorities of the Earth Institute’s new Initiative on Communication and Sustainability is improving the interface between journalists, scientific expertise and vulnerable communities. This is the latest webinar in a series I’m developing on covering factors that either boost or impede community and ecological resilience in the face of the landscape of hazards in this era of rapid change. More videos can be found on the Resilience Media Project page.

Journalist Resources

Jeff Schlegelmilch, director of the National Center for Disaster Preparedness at Columbia University’s Earth Institute, speaks with public radio reporter Eve Troeh about how journalists should cover disasters.

Covering Recovery: Finding News in the Aftermath of Disaster

Basic definitions of hazards from the International Federation of Red Cross

Resources for basic information on hazard/risk

National Center for Disaster Preparedness (Columbia University)

United Nations Office for Disaster Risk Reduction (UNDRR)

A primer on 21st century megadisasters from Jeff Schlegelmilch, director of the National Center for Disaster Preparedness. (Jeff is available for interviews.)

Understanding and managing connected extreme events

Compound risk – Heat and Drought

How Rossby waves can affect people thousands of miles away

A typology of compound weather and climate events

Compound Risk – COVID-19

Compound climate risks in a COVID-19 world

Wildfire Resources

The National Wildfire Coordinating Group (NWCG) – COVID and Fire

California FireSafe Council – Wildfires and the Pandemic

The federal government’s National Interagency Fire Center is a place to go for information on the current fire outlook and more. They also have resources on COVID and fires, including area plans

Story Ideas (Entry points for your first stories)

The Resilient Children/Resilient Communities Initiative has a toolbox with resources to help children become more resilient to disasters. This is a great resource for finding stories in your community.

Use the U.S. Natural Hazards Index to find story ideas on risk for your community.

One future issue reporters should be writing on today is extreme heat, also known as “wet heat.” Background on extreme heat from Climate Central and from Science.

COVID-19 resources

Coronavirus: expert resources for journalists

Is your community fire adapted?


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