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Intended to supplement undergraduate college geography courses, this resource paper investigates the need and use of radar in weather phenomena research. Radar can be used to study weather phenomena over a wide area, thus improving the results of statistical analyses previously limited by inadequate data. Radar techniques are also useful for probing small area weather phenomena, such as thunderstorms, which may occur between existing climatological stations. Most radar studies of a climatological nature have concerned the distribution of rain showers or the determination of rainfall amounts in inaccessible areas. Studies of this type are reviewed, as well as potential areas for further investigation. A case study is presented in which radar is used to examine the effect of air-mass convective rainfall on average maximum air temperatures. This study shows how radar data may enhance the results of conventional statistical analyses of climatological variables. (Author/MLH)

Intended as a supplement to undergraduate college geography courses, this resource paper reviews the mechanism by which surface weather features are linked with the mid-atmospheric circulation within the westerly wind belt. Specifically, vertical atmospheric motions associated with certain aspects of the upper tropospheric flow, including jet streams, are discussed. Processes at this level are related to such surface weather features as cyclones, anticyclones, and air masses, and the way these are modified and steered across the country. The evolution of monthly flow patterns during the period October-December, 1951, are discussed. These three months are useful as a case study because of the close geographical agreement between middle level flow patterns and surface weather departures from normal over the United States; these three months are also noteworthy because of the record setting temperature and precipitation values recorded over wide areas. As an exposition of the relationship between mean tropospheric flow and surface weather patterns, this review describes many of the basic principles underlying extended period weather forecasting as well as the evolution of daily weather over the country as it undergoes monthly or seasonal changes. (Author/MLH)

Intended to supplement undergraduate college geography courses, this resource paper investigates several concepts which are prerequisite to the study of physical geography. The student is provided with a "systems" approach to physical geography, which combines the underlying principles of physics with the contextual application of these principles to the specific domain of physical geography. The particular framework introduced is based upon the idea that nature tends to remain in steady states through the action of internal regulation mechanisms known as feedback. The underlying physical principle is one of conservation: the conservation of mass, energy, and momentum. Examples are given to illustrate these conservation laws and how they ultimately account for the weather and erosion. The general circulation of the atmosphere is described and provided as an explanation for climatic conditions, such as precipitation and wind effects. Fluvial erosion is presented as another example of feedback operations, in which energy is traced from its source in the atmosphere through a number of steps to stream flow. (Author/MLH)