I recently returned from a convention in Las Vegas. It was 110 degrees every day I was there. A lot of long-time visitors to Las Vegas say that it seems that Las Vegas is getting hotter, but most of them assume that its just their imagination. It isn’t. Las Vegas really is getting hotter. According to the U.S. Weather Service, the average daily temperature in Las Vegas has risen by 6 degrees since 1970. That is a very big increase for 50 years. You might assume that this is because of global warming, but that isn’t the reason. Las Vegas is what climatologists call a ‘heat island’. In 1940, the population of Las Vegas was just 8,000. When I first visited Las Vegas in 1970, the population of the city was a little over 100,000. Today, the Las Vegas metro area is home to 2 million people, and the temperature has risen with the population. Here’s why:
1. Building materials. As the city grew, more and more of the desert was covered with concrete, asphalt, and buildings. Buildings and paving materials absorb heat during the day and release that heat more slowly than the sandy desert that they covered over.
2. Color. The desert around Las Vegas is mostly light-colored sand, which reflects much of the sunlight that falls on it back into outer space. However, the streets of Las Vegas are covered with asphalt, which is black, and there are tens of thousands of houses in Las Vegas covered with dark colored roofs, which also absorb heat.
The air. As the city grew, so did the number of
automobiles, trucks, and smokestacks. When Las Vegas was a
small town, the air was thin and clean. Now the air is much denser and full of
smog. The air in Las Vegas now absorbs more heat than the air in the desert
What is happening in Las Vegas is also happening in Phoenix and several other fast-growing cities in the southwest. Some long-term real estate investors (including people I know) will not invest in Las Vegas. It can take 15 to 20 years to recover the cost of building an apartment house, and what will the climate in Las Vegas be like then? What will the air be like? What will the traffic be like? Will tourists still want to visit there if the average daily temperature in summer is 120 or 130 degrees? Las Vegas is heading in that direction now. I’ve been in Las Vegas when it was so hot that you could get a first-degree burn by touching something made out of metal, and that happened to me. I once tripped on the sidewalk in front of Circus Circus and put my hand on an aluminum lamppost to break my fall, and I burned my hand. Now, I don’t touch anything outdoors in Las Vegas that is made out of metal on hot days unless it is in the shade.