Introduction to Meteorology

INTRODUCTION TO METEOROLOGY JAY-AR L. CELESTE, RFP  The earth is surrounded by a large envelope of gases called atmosphere. The condition of the atmosphere and the changes it undergoes influence all physical, chemical and biological activities over the earth. In modern usage...

INTRODUCTION TO METEOROLOGY JAY-AR L. CELESTE, RFP  The earth is surrounded by a large envelope of gases called atmosphere. The condition of the atmosphere and the changes it undergoes influence all physical, chemical and biological activities over the earth. In modern usage, meteorology denotes the science of weather and includes the study of atmospheric phenomena. Definition Meteorology can be defined as the science that deals with the study of the atmosphere.. Marine meteorology: Meteorology pertaining to the sea and ocean is called marine meteorology. Aeronomy: The science of aeronomy Divisions of investigates both the chemical and physical properties of the atmosphere Meteorology and the changes that occur in these as the result of external and internal forces. Bio-meteorology: The scientific study of the interactions between living organisms and their atmospheric environment called biometeorology.  The word ‘weather’ refers to short period variation in the atmosphere at a given place. Weather at any place is defined as the momentary condition of the atmosphere. The condition of the atmosphere depends on the following variables which are called weather elements. They are 1) temperature of the air, 2) pressure, Weather 3) humidity, 4) rainfall and 5) wind. Among these, temperature is the most basic and fundamental. Any change in temperature causes change in the other elements.. Troposphere From surface towards upwards temperature decreases with altitude. This region is called troposphere. Stratosphere Above the troposphere is an isothermal layer followed by a region of inversion extending upto nearly 50km. This is termed as the stratosphere. Thermosphere Temperatures rise rapidly above the mesopause, reaching nearly 1000˚C by about 300km. This region is known as the thermosphere. Mesosphere Above the stratosphere is the mesosphere extending from roughly 50 to 80km. The temperature in this region once again decreases with altitude, lowering to about -95˚C at the mesopause around 80km. Exosphere The lighter gases, hydrogen and helium, slowly become free of the earth’s gravitational field and escape to space by about 600km. This region has been named as the exosphere, which gradually merges into the interplanetary space. Gases The atmosphere we live in is a mixture of gases composed mainly of nitrogen and oxygen. The proportion of the various gases in the atmosphere by volume is 78 percent nitrogen, 21 percent oxygen and the rest 1 percent made up of small amounts of argon, carbon dioxide, neon, helium, krypton, xenon, hydrogen and traces of ozone, methane, sulphur dioxide, nitrogen oxides etc. Water vapor Water vapor is present in varying proportions. The moisture content in the atmosphere varies depending on the latitude, temperature, wind, and atmospheric systems. Water vapor decreases as altitude increases. Aerosols Atmospheric aerosols are a suspension of fine solid and liquid particles in the atmosphere. These clouds of suspended matter range from dust and smoke to mists, smogs and haze. They are not always the result of pollution from human activities; some enters the atmosphere from volcanic eruptions or dust storms.