It's Hot. The Urban Heat Island Effect.

It’s been extremely hot this year, and many people jump to blame climate change, but no one talks about the underlying reason. The reason why specifically growing urban areas like Phoenix are maintaining these scorching temperatures is due to the Urban Heat Island Effect. (www.heat.gov)

Major media doesn’t discuss this enough because it doesn’t encourage further development, which happens to be the primary economic model for the Greater Phoenix Area. They’ll tell you there’s a drought and ask you to conserve water, but then they build and build, expanding far beyond the original boundaries of the city. Meanwhile, concrete, asphalt, and other man-made materials are trapping heat, radiating it back into the air at night, and making it harder for the environment to cool down.

The floor is lava: https://www.reuters.com/graphics/CLIMATE-CHANGE/URBAN-HEAT/zgpormdkevd/

According to research shared on heat.gov, cities like Phoenix experience significantly higher temperatures than rural or undeveloped areas due to the concentration of concrete, asphalt, and other man-made materials that absorb and retain heat throughout the day. These materials can become as much as 95% hotter than natural surfaces like soil or grass, leading to a noticeable increase in overall air temperature. I have personally measured the difference between grass, asphalt, concrete, and astroturf – the differences are astounding. When it was 110 degrees out, the asphalt was 165 degrees, while the grass was just under 90, and the shaded grass was 83 degrees. The newly installed astroturf was at the same temperature as the asphalt at 165 degrees.

This isn’t just uncomfortable for us—it’s deadly for our iconic desert plants. Saguaros rely on a process called transpiration to cool themselves at night by opening their stomata, which allows them to release heat and moisture. But in urban areas filled with concrete and asphalt, the stored heat radiates back into the environment at night, preventing the cacti from cooling off properly. As a result, many are literally boiling from the inside, leading to widespread rot and death in urbanized zones, while those in undeveloped desert areas are thriving. Out where I live in the rural desert, the saguaros are thriving, but within the town limits of Anthem, we lost roughly 80 saguaros last year to them boiling out.

https://19january2021snapshot.epa.gov/heatislands/learn-about-heat-islands_.htmlhttps://www.rff.org/publications/explainers/urban-heat-islands-101/

Contrast this with cities like Flagstaff, where expansive green spaces and natural landscapes help regulate the climate, keeping temperatures cooler and less extreme. This shows us that how we build our cities matters—reducing the number of heat-absorbing surfaces and integrating more green spaces can make a real difference.

It’s clear that rapid urban development is exacerbating these extreme heat events, impacting not only human health but also the survival of plant life that’s critical to our desert ecosystem. If we want to preserve our natural heritage, we need to rethink how we plan our cities and neighborhoods.