Climate change is often discussed in terms of rising temperatures and melting ice caps. Still, its effects on human health, particularly for Wisconsin's most vulnerable residents, are much closer to home. What does a historic Milwaukee flood have to do with mental health? How does green schoolyard infrastructure protect children? And why does it matter who causes climate change versus who suffers most from it?
Key Takeaways:
Climate change is more than global warming. While rising temperatures are a central feature, Dr. Beyer emphasized that "global climate change" better captures the full picture: interconnected shifts across earth systems—water, air, soil, and temperature—that manifest as droughts, floods, and regional weather disruptions with wide-ranging environmental health consequences.
"It's a better term to use global climate change than global warming because it really captures the interconnectedness and the complexity of what's happening to the planet," Dr. Beyer explained.
Dr. Beyer highlighted a key disconnect: who causes climate change and who suffers most from it are not the same people. Higher-income, industrialized nations emit far more greenhouse gases, yet lower-income and equatorial countries face the most severe consequences. The same dynamic plays out domestically—in Wisconsin and across the U.S., the populations least responsible for emissions face the greatest health disparities.
Housing stability, access to healthy food, and the ability to afford energy costs are social determinants of health that climate change puts further out of reach for vulnerable communities. People experiencing homelessness are directly exposed to extreme heat and flooding without the protection of a stable shelter. Children are physiologically more susceptible to heat stress and have little power to address the forces shaping their future. Urban heat island effects make cities like Milwaukee especially prone to temperature extremes.
In August 2025, Milwaukee County received more than 14 inches of rain in 24 hours—a 1,000-year flood event. The city's combined sewer system was overwhelmed, prompting the Milwaukee Metropolitan Sewerage District (MMSD) to release more than 5 billion gallons of water into local waterways to prevent sewage from backing up into homes. Two unhoused men were confirmed dead, with two others still missing.
The flood also left standing water ideal for mosquito breeding, raising concerns about vector-borne diseases. At the same time, mold growth in flooded homes created additional environmental health hazards. Dr. Beyer noted that while most people recognize the visible dangers of flooding, the indirect consequences—mental health impacts, trauma, post-traumatic stress disorder, and mold—often go overlooked. Warmer temperatures and wetter conditions are also expanding the range of ticks, leading to rising Lyme disease rates across the state.
One of the most compelling examples of climate resilience in Wisconsin is a green infrastructure initiative led by Reflo, a Milwaukee nonprofit, in partnership with MMSD, the City Sustainability Office, and Milwaukee Public Schools. The project converts asphalt-heavy schoolyards into green spaces with trees that on-site absorb stormwater. Across converted schools, the infrastructure is projected to capture 4 million gallons of stormwater.
The benefits extend well beyond stormwater management. Shade trees reduce the urban heat island effect. Green spaces lower stress and support mental health. Children who spend time in nature show better focus and academic performance. These schoolyards illustrate a core principle that Dr. Beyer returned to throughout the conversation: the best climate solutions improve public health across multiple dimensions simultaneously.
Mental health is a thread that runs through the entire conversation about the health effects of climate change. Extreme weather causes trauma and displacement. Heat stress affects mood and cognition. The anxiety of watching climate conditions worsen takes its own toll.
"One of the things that I focus on the most in my research is the mental health and well-being aspect of all of these things," Dr. Beyer said. Many climate solutions—active transportation, green space, community connection—are also proven mental health interventions, making the case for addressing both together.
Dr. Beyer stressed that addressing the health impacts of climate change requires partnerships across sectors, including public health, housing, education, nonprofits, and city government. She pointed to several local resources and organizations advancing environmental health equity in Wisconsin:
At the individual level, advocating for green space in homeowners' associations and neighborhoods, reducing home energy use, and simply spending more time outdoors and encouraging others to do the same are all meaningful starting points.
When asked what gives her hope, Dr. Beyer pointed to two sources: the dedicated professionals working tirelessly on climate and health solutions, and the children who look at the problem with fresh eyes and can't understand why adults aren't simply fixing it.
"I think that gives us a lot of hope for the future," she said.
To learn more about climate change and community resilience, watch the full Coffee Conversations with Scientists episode with Dr. Beyer, below: