CHAPTER 1
CLIMATOLOGY AND ITS APPLICATIONS
1. Climatology: An Atmospheric Science
Atmospheric scientists often subdivide study of complexity of gaseous envelope that
surrounds the earth into specific areas of interest. One such division identifies the fields of
meteorology and climatology. Meteorology is a science that deals with motion and the
phenomena of the atmosphere with a view to both forecasting weather and explaining the
processes involved. It deals largely with status of atmosphere over a short period of time and
utilizes physical principles to attain its goal. Climatology is the study of atmospheric
conditions over a longer period of time. It includes the study of different kinds of weather
that occur at a place. Dynamic change in the atmosphere brings about variation and
occasionally great extremes that must be treated on the long term as well as the short term
basis. As a result, climatology may be defined as the aggregate of weather at a place over a
given time period.
There is diversity of approaches available in climate studies. Figure 1. Illustrates the
major subgroups of climatology, the approaches that can be used in their implementation, and
the scales at which the work can be completed.
Figure 1. Subgroups, Analytical methods and scales of climatic study.
,Climatography consists of the basic presentation of data and its verbal or cartographic
description.
Physical Climatology deals largely with the energy exchanges and physical components.
Dynamic Climatology is more concerned with atmospheric motion and exchanges that lead
to and result from that motion.
Applied Climatology is the scientific application of climatic data to specific problems within
such areas of forestry, agriculture, and industry. It can involve the application of climatic data
and theory of other disciplines, such as geomorphology and soil science.
The analytical approaches suggested in the above figure 1. are self-explanatory, with
the possible exception of the synoptic approach, an analytic method that combines each of the
others. The object of synoptic climatology is to relate local or regional climates to
atmospheric circulation.
, 2. Temperature structure of the atmosphere
In general terms, the atmosphere can be considered as a series of concentric layers or
shells surrounding the earth. The most commonly used method to describe atmospheric
layering uses temperature as the variable. This is illustrated in Figure 2. , which shows
temperature changes with height.
The troposphere is the lowest level, where “weather” occurs. In this layer, there is
generally uniform decrease of temperature with height. The lowest part of the troposphere, up
to 1.5 km or 2 km is called friction layer. The upper limit of the troposphere is the
tropopause. It is zone where generally decrease of temperature ceases and temperature
remains fairly constant with height (isothermal-equal temperature). The tropopause also
represents the upper limit of large scale turbulence and mixing of the layer.
The stratosphere extends from the 10 km to 45 km above the surface. In this lower
section, temperatures are fairly constant, but at an elevation of 30 km they increase toward
the upper limit of this zone, the stratospause. Air circulation in the stratosphere is
characteristically persistent, with winds blowing at high velocities.
The mesosphere, above the stratopause, is identified by a marked temperature
decrease with altitude. Beginning at an elevation of about 80 km, the decline continues until
the mesopause is reached.
The thermosphere lying above the mesopause has no defined upper limit. It is so
named because a very high thermodynamic temperature attained.
Figure 2. Thermal Structure of Atmosphere
, Figure 3. Schematic cross section of Earth's Atmosphere showing
broad chemical dividions
CLIMATOLOGY AND ITS APPLICATIONS
1. Climatology: An Atmospheric Science
Atmospheric scientists often subdivide study of complexity of gaseous envelope that
surrounds the earth into specific areas of interest. One such division identifies the fields of
meteorology and climatology. Meteorology is a science that deals with motion and the
phenomena of the atmosphere with a view to both forecasting weather and explaining the
processes involved. It deals largely with status of atmosphere over a short period of time and
utilizes physical principles to attain its goal. Climatology is the study of atmospheric
conditions over a longer period of time. It includes the study of different kinds of weather
that occur at a place. Dynamic change in the atmosphere brings about variation and
occasionally great extremes that must be treated on the long term as well as the short term
basis. As a result, climatology may be defined as the aggregate of weather at a place over a
given time period.
There is diversity of approaches available in climate studies. Figure 1. Illustrates the
major subgroups of climatology, the approaches that can be used in their implementation, and
the scales at which the work can be completed.
Figure 1. Subgroups, Analytical methods and scales of climatic study.
,Climatography consists of the basic presentation of data and its verbal or cartographic
description.
Physical Climatology deals largely with the energy exchanges and physical components.
Dynamic Climatology is more concerned with atmospheric motion and exchanges that lead
to and result from that motion.
Applied Climatology is the scientific application of climatic data to specific problems within
such areas of forestry, agriculture, and industry. It can involve the application of climatic data
and theory of other disciplines, such as geomorphology and soil science.
The analytical approaches suggested in the above figure 1. are self-explanatory, with
the possible exception of the synoptic approach, an analytic method that combines each of the
others. The object of synoptic climatology is to relate local or regional climates to
atmospheric circulation.
, 2. Temperature structure of the atmosphere
In general terms, the atmosphere can be considered as a series of concentric layers or
shells surrounding the earth. The most commonly used method to describe atmospheric
layering uses temperature as the variable. This is illustrated in Figure 2. , which shows
temperature changes with height.
The troposphere is the lowest level, where “weather” occurs. In this layer, there is
generally uniform decrease of temperature with height. The lowest part of the troposphere, up
to 1.5 km or 2 km is called friction layer. The upper limit of the troposphere is the
tropopause. It is zone where generally decrease of temperature ceases and temperature
remains fairly constant with height (isothermal-equal temperature). The tropopause also
represents the upper limit of large scale turbulence and mixing of the layer.
The stratosphere extends from the 10 km to 45 km above the surface. In this lower
section, temperatures are fairly constant, but at an elevation of 30 km they increase toward
the upper limit of this zone, the stratospause. Air circulation in the stratosphere is
characteristically persistent, with winds blowing at high velocities.
The mesosphere, above the stratopause, is identified by a marked temperature
decrease with altitude. Beginning at an elevation of about 80 km, the decline continues until
the mesopause is reached.
The thermosphere lying above the mesopause has no defined upper limit. It is so
named because a very high thermodynamic temperature attained.
Figure 2. Thermal Structure of Atmosphere
, Figure 3. Schematic cross section of Earth's Atmosphere showing
broad chemical dividions
