Originally published in The Technology Teacher, May/June 2002, by the International Technology Education Association
Become a Weather Wizard!
is going to happen in the next 12 to 24 hours. If it’s a hurricane about to come ashore on the east coast of the U.S., 12 hours’ warning can save hundreds of lives, giving people the opportunity to evacuate inland or go to higher ground. Of course, it is very important that such warnings be highly accurate, or people won’t pay any attention to them. They will think that the weather forecasters are just crying “Wolf!” one more time.
In some places—maybe where you live— weather is a very important part of planning, especially leisure time planning. For example, in looking forward to your weekend, wouldn’t it be nice to know it was going to be sunny and clear on Saturday, but rain buckets on Sunday? That way, you’d have a good reason for putting pleasure before business, planning something fun outdoors for Saturday and your homework for Sunday.
Weather is just about the most complex and unpredictable natural occurrence humans have to deal with. How- ever, predicting weather is finally getting to be less of an art and more of a science. Using images and other data from the GOES* environmental satellites and other kinds of sensing technologies, and computers to analyze the data, scientists are beginning to make some sense of it all. For example, thanks in part to real-time (meaning right this second) information from the GOES, meteorologists (scientists who study the weather) have gotten very good at predicting what
On TV weather reports, you’ve probably seen weather forecasters point to maps and use terms like “cold front,” “high-pressure system,” “baro- metric pressure,” and “jet stream” to describe the major trends and weather systems influencing our entire continent. In addition to showing satellite images of clouds, TV forecasters and newspapers sometimes uses lines and symbols on a map to help convey this big picture. Of course, this map of an area over 3,000 miles wide and just about as long will not tell you whether it is snowing right this second in downtown St. Paul or hailing in east North Hampton. It will tell you what kind of weather each of those local places is most likely having.
Let’s learn to read one of these maps—or even draw one. First, we need to understand a little about what the symbols mean. Here are the most common weather concepts you will see illustrated on a weather map. There’s a whole lot more to know about all these ideas, but these explanations may get you started.
High and Low Pressure Areas:
Did you realize that you have hundreds of pounds of air pushing on your body all the time? Of course, your body evolved under all this pres- sure, so you can handle it! (That’s why astronauts need pressurized space suits to do their space walks. Otherwise, they’d explode!—well, not really, but their blood would boil, which is just as unpleasant.) All the air above you in the atmo- sphere is being held near Earth’s surface by grav-
For Geostationary Operational Environmental Satellites