Chasing thunderstorms in the Arizona desert? Surely, one would imagine that better storm chasing conditions are found in other parts of the country, say the Great Plains. Yet, surprisingly, for a couple of months every year some of the most unusual and fascinating storms in the country occur in the southwestern United States associated with a phenomenon called the "Arizona Monsoon." The monsoon is defined by a seasonal shift in winds, which brings moisture up into Mexico and Arizona from the Pacific and the Gulf of Mexico. This moisture, coupled with intense surface heating, creates massive thunderstorms with almost all of the characteristics of Great Plains thunderstorms except for tornadoes. In addition, Southwest thunderstorms have many unusual features, such as "gustnadoes" (strange combinations of tornadoes and dust devils, see photo below) and "microbursts" (explosive "air bombs" of sinking air).
In the summer of 1989, a unique project began in Phoenix, Arizona as a joint effort between the Department of Geography at Arizona State University (ASU) and the Phoenix Forecast Office of the National Weather Service. That project has become known as the Arizona Thunderstorm Chasers or AZTC. Since its inception, AZTC has (a) aided in the detection and warning of severe weather in metropolitan Phoenix; (b) been affiliated with an international project investigating the Arizona Monsoon (the Southwest Area Monsoon Project or SWAMP) under the direction of the National Severe Storms Laboratory in Norman, OK; and (c) received international recognition with the publication of an article describing AZTC which appeared in the primary journal of professional meteorologists, the Bulletin of the American Meteorological Society (June, 1992).
Arizona State University geographers, including Dr. Randy Cerveny, designed the Arizona Thunderstorm Chase Program to address four major goals:
When chasers head out to monitor a storm, they are sent out in teams to accomplish several things. First, as they are taking weather readings (wind, temperature, rainfall, etc.) with portable weather stations, they are also providing on-site, visual reports by cell phone and radio of developing weather to the National Weather Service so that NWS can put out better information and warning to the Phoenix metropolitan area. They are also getting the chance to use their classroom knowledge of how storms develop in a "real-world" situation as they make quick decisions as to "where would be the best place to go," "how close can they get," or " the change of severity in the situation." And even after the storm is over, the Arizona chasers' work isn't necessary done. Storm chasers interview witnesses, photograph and videotape damage, and survey the area that has been hit. This type of damage assessment--documenting what happened and how it happened--is critical information for weather experts.
The AZTC project has succeeded far beyond the original expectations. Former chasers--with unique and valuable experience gained from AZTC--are now employed with the National Weather Service, with the Arizona Department of Environmental Quality, with private and public companies (such as the power/utility organization, Salt River Project), and with Arizona State University as geography graduate students. Many of the chasers have commented that their experiences with ATZC helped in their ability to land a job.
According to the information presented in the chapter on Weather (Chapter 8 in Geosystems and Chapter 5 in Elemental Geosystems), thunderstorms and tornadoes are two types of severe weather. Compare and contrast the two types of violent weather. Why is Arizona a good place to study (or "chase") thunderstorms and the Midwest a good place to study (or "chase") tornadoes?
To create paragraphs in your essay response, type <p> at the beginning of the paragraph, and </p> at the end.
