Climate ClassificationThe purpose of classification is to organize a set of data or information about something to effectively communicate it in an informative way. Classification helps synthesize information into smaller units that are more easily understood. When considering the Earth's climate, there is such an enormous amount of information that one has to break it down into areas of commonality to easily understand it. Climatologists have therefore created several ways to organize the wealth of information about Earth's climate to bring order and understanding to it. Climate classification systemsThere are three fundamental types of classifications used in climatology. First there are empirical systems of classification that are based on observable features. The Koeppen system discussed below is an empirical system based on observations of temperature and precipitation. These are two of the easiest climate characteristics that can be measured, and probably the ones with the longest historical record. It's fairly easy to collect air temperature readings with a thermometer and precipitation with some sort of collecting device that can measure the amount of precipitation. Climates are grouped based on annual averages and seasonal extremes. Genetic classification systems are those based on the cause of the climate. A genetic system relies on information about the climatic elements of solar radiation, air masses, pressure systems, etc. The important point here is that we assume we know what causes climate. Though atmospheric science is progressing everyday, we still have a long way to go before we have a complete understanding of the workings of our climate. These are inherently the most difficult classifications to create and use because of the multitude of variables needed. Applied classification systems are those created for, or as an outgrowth of, a particular climate-associated problem. The Thornthwaite classification system is one based on potential evapotranspiration and thus groups climates based on water requirements. Research conducted by C.W. Thornthwaite and his associates attempted to formulate a water budget technique that assessed water demand under different environmental conditions. His classification system grew out of the issue of trying to predict the supply and demand for water in different climate regions. Koeppen systemThe Koeppen system is one of the most widely used systems for classifying climate because it is easy to use and data requirements are minimal. For information about the system see:
Figure 9.1 World Climate patterns according to
Koeppen |
