Urban heat islands in the Great Lakes are endangering public health

Heat islands created by buildings and paved surfaces are raising temperatures and health risks in cities like Toronto and Windsor.

Lisa John Rogers reports for Great Lakes Now.


In short:

  • Urban heat islands in Great Lakes cities absorb and re-emit heat, increasing temperatures and health risks.
  • Vulnerable populations, including low-income and racialized communities, are disproportionately affected.
  • Long-term heat mitigation efforts exist, but short-term heat management strategies are insufficient.

Key quote:

“Without a doubt, I think every emergency department across the country during the heat spells, especially when the heat gets above 88 to 90 degrees, experiences an influx of people, especially in the heat islands.”

— Dr. Patrick McHugh, emergency room physician, Cleveland Clinic

Why this matters:

Increasing urban heat poses significant health risks, especially to vulnerable populations, exacerbating existing health inequalities. For residents, especially the elderly and those with preexisting health conditions, the effects can be severe. Elevated temperatures contribute to heat-related illnesses, increase air pollution levels, and strain energy resources as people rely more heavily on air conditioning. This creates a vicious cycle, as increased energy use further amplifies urban heat and greenhouse gas emissions.

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