I recently came across an article saying that the urban core of Miami, where I live, is turning into Shanghai. I’ve never been to Shanghai, but I don’t think the comparison was meant as a compliment. The author was noting the relentless development in downtown Miami, where construction fencing cordons off every remaining plot of grass or empty parking lot.
I care little about the aesthetics of urban sprawl. Instead, I am concerned about the growing traffic problems, and alarmed that a forest of concrete towers will block out the sun.
Morning Sun
At daybreak, the sun’s low angle means that sunlight must pass through a much thicker portion of the atmosphere compared to midday. As a result, morning sunlight is predominantly red and infrared light because these longer wavelengths can punch through the atmosphere and diffuse through the sky, while shorter wavelengths get scattered. The physics that allows red and infrared light to survive the trip through the Earth’s atmosphere also enable these wavelengths to reach you even if the sun is obscured by trees, buildings, or clouds.
The key takeaway is that you should go outside at sunrise whether you can see the sun or not. Red and infrared light, fundamental to health, remain accessible even when a high-rise blocks your direct line of sight to the sun. Dawn illumination and the presence of red, infrared, and scattered blue light sends a vital signal to the part of your brain that controls your circadian rhythm. The message to your suprachiasmatic nucleus (SCN) is: start your cells’ daytime program.
On the other hand, city dwellers do need to make an effort to get their UV light directly from the sun. UV light is more easily blocked by obstacles like tall buildings because of their shorter wavelengths.
A lack of UV light is a significant concern because of the impact of UV light on levels of: nitric oxide (blood pressure), vitamin D (immune system), melatonin (antioxidant, restorative sleep), alpha-MSH (appetite and glucose regulation), and more.
I can say for cetain that in Brickell, gridlock is approaching. Fortunately, when you’re forced to give up your car and walk instead, your morning stroll will do wonders for your health.