The sky is not falling Jon Tarleton Marketing Manager and Meteorologist Vaisala St. Louis, Missouri
e all know the story of Chicken Little, right? He is hit on the head by an acorn and proceeds to run and tell everyone the sky is falling. If you are a Chicken Little, in 2012 you likely were doing just that based on all the wild and crazy weather we had this year. From a record-breaking mild winter of 2011-12, and early spring, forest fires in the west, and the extreme drought over much of the Midwest you might easily connect with the “sky is falling” storyline. In road maintenance our lives are very much determined by the weather, so it is only natural to ask the question, “What is going on with the weather?” The simple answer, “change,” but before you stop reading and assume this is another article about global warming, please wait! Let me define what I mean by change. It is a known fact that the weather on our planet has never remained constant. Ice ages, deserts where there were once oceans, and the tropical climate scientists believe the dinosaurs once enjoyed, are all concrete signs that our climate is constantly changing. The first thing we must remember is that meteorologists have only been gathering true scientific measurements on a global scale for a little more than one hundred years. Much of what we know about before that is from either crude observations or other things on our planet that record climate information (such as tree rings and ice cores from the polar ice, etc.). What I am not going to do is give you my opinion as to 38 APWA Reporter
November 2012
why it is changing. I will remind you that all the different reasons you have heard are a theory, and it is nearly impossible to determine the true cause. I would also like to point out that now, and in the past, our “Chicken Little” has been the media. They love to start off a newscast with a terrible scene from a storm and the headline, “Was today’s storm caused by global warming?” Change is occurring now, and the weather will always be changing, so questions remain as to what change will mean. Are we in store for more winters like last year? Are droughts going to become normal for the Midwest, and will the polar ice caps melt? Sorry, this answer is not so simple, and it’s, “We don’t know.” We do have computer models that
can try and predict what changes might occur, and what our climate might look like, but the atmosphere is so complex. For example, if the temperature did rise we will likely have more moisture in the atmosphere, which means more clouds, which reflect heat from the sun, and thus, cool the surface. The increase in cloud cover would balance out the temperature increase. Also, as I mentioned earlier, we would need to know for sure what is causing the change. Since the weather was changing before the industrial revolution and our modern-day industrial world, if it wasn’t humans, what was it? We know for a fact that other factors are at work in climate change; one example is the sun. The sun, our only true source of heat to sustain life, does not provide a fixed
In road maintenance our lives are very much determined by the weather.
