The urban heat island effect exacerbates health risks, particularly for vulnerable populations such as older adults, outdoor workers, children, and those with chronic illnesses. Heat-related illnesses, including heat exhaustion and heat stroke, are more likely in areas with limited shade and high temperatures. The EPA notes that shaded surfaces can be 20 to 45°F (11 to 25°C) cooler than unshaded ones, highlighting the critical role of green spaces. Additionally, Houston's reliance on cars and industrial activity worsens air quality, with ground-level ozone pollution posing further health risks.