Climate is the analysis of weather of a given place an extended period of time. By comparison, weather refers to the atmospheric conditions over a short period of time, such as hours, days, or weeks. The World Meteorological Organization (WMO) considers climate to be the average weather over a period of 30 years, but this period can vary. Climate is determined by analyzing meteorological variables such as wind, humidity, temperature, precipitation, and atmospheric pressure. Another variable that is often considered is the count of particles in the atmosphere. The climate system, which generates the climate of a place, has five main components: the atmosphere, cryosphere, lithosphere, biosphere, and hydrosphere.
Several factors play a role in determining the climate of a given place. These factors include the altitude, latitude, nearby water bodies, and local terrain. In order to classify the climate, meteorologists often use a system known as the Köppen climate classification. However, other notable classification systems include the Thornthwaite system and the Bergeron and Spatial Synoptic Classification system.
Methods of Classification
Köppen Climate Classification
The Köppen climate classification is currently the most widely used system of determining the climate of a region. It is an empirical method of climate classification that focuses on average monthly values of a region’s precipitation and temperature. The most common system has five types with labels that range from A to E, which represent tropical, dry, mild mid-latitude, cold mid-latitude, and polar climates, respectively. Further subdivisions of these types include tropical savannah, humid continental, humid subtropical, Mediterranean, and polar ice cap climates. A limitation of the Köppen climate classification, like other methods, is that it assumes that climate zones have distinct boundaries. In practicel, however, transitions between weather zones are more gradual.
The Thornthwaite method measures climate by analyzing the moisture content in soil using evapotranspiration. Created in 1948 by American geographer and climatologist C. W. Thornthwaite, the method measures the amount of moisture used to sustain plant life in an area. The values are then used to create an index which describes how wet or dry an area is. The higher the index, the wetter the climate, and vice versa. Semi-arid values usually fall between -20 and -40, while arid areas have a value below -40. In addition to climate classification, the Thornthwaite system can also determine the number of mammals and herbivores in an area.
Bergeron and Spatial Synoptic
The Bergeron and spatial synoptic classifcation is the most simple climate classification method, and also the wide commonly accepted means of air mass classification. The Bergeron classification of air masses has three letters. The first letter describe the moisture of an air mass, such as "c" for a continental dry air mass, or "m" for a moist maritime air mass. The second letter describes the thermal properties of the air mass, and examples include T (tropical), P (polar), A (Arctic or Antarctoc), M (monsoon), E (equatorial), or S (superior air, which is dry). The last letter denotes the atmosphere’s stability, and "k" represents an air mass that is colder than the ground below, while "w" represents an air mass that is warmer than the ground below.