Introduction to environment & Atmosphere.pptx

Environmental studies

1. Introduction to Environment and Environmental Studies By Salma Sultana Guest Faculty Department of Geography Ravenshaw University, Cuttack

2. Environment The word ‘environment’ is derived from the French word ‘ environner ’ which means to encircle or to surrounds According to P.Gisbert “Environment is anything immediately surrounding an object and exerting a direct influence on it”. Environment : Living + Non-living things (Influencing one another) Environmental Studies: Educating People= Preserving quality environment

3. Importance of Environmental Studies Environmental studies is recognized as the process that would help individuals to acquire essential knowledge and skills to take positive action towards a better environment. To know more sustainable way of living. To use natural resources more efficiently. To know the interrelationship between organisms in populations and communities. To aware and educate people regarding environmental issues and problems at local, national and international level.

4. Components of Environment

5. Atmosphere Atmosphere is the thick gaseous envelop which surrounds the earth and is attached to the ground surface by gravitational force. It is estimated that 97% of the effective atmosphere is confined up to a height of 29 km above the earth’s surface. Providing oxygen for respiration. Regulating temperature. The greenhouse effects of certain atmospheric gases, like water- vapor and carbon dioxide, helps trap heat from the sun and maintain a habitable temperature range on the planet’s surface. Protecting against harmful radiation.

6. Composition of Atmosphere Atmosphere is composed of different gasses and water vapor.

7. Structure of Atmosphere

8. Troposphere Troposphere is the lowest layer of the atmosphere where temperature decreases with increase in altitude. Almost all weather phenomena including clouds, rain, wind etc. occurs within this layer. Troposphere extends up to 16 km above sea level. The boundary between the troposphere and the stratosphere is called tropopause .

9. Stratosphere Stratosphere is the 2 nd layer of the earth’s atmosphere. Extends from top of the troposphere to about 50 km above earth’s surface. This layer contains most of the ozone layer. Ozone layer in stratosphere absorb high energy ultraviolet rays from sun. Jets often fly here because it is calm.

10. Mesosphere The mesosphere lies between the thermosphere and the stratosphere . Third layer of the earth’s atmosphere. Extends from 50 km above the earth surface to 80 km. Temperature decrease with increase in altitude. Mesosphere is the region where most meteors burn up as they enter the Earth’s atmosphere. So p rotects the earth from falling meteors.

11. Thermosphere Thermosphere is a layer of the earth atmosphere located above the mesosphere and below the atmosphere. It extends from approximately 85 kilometers in altitude to around 600 kilometers. In this layer temperature increases with increase in altitude.

12. Ionosphere Ionosphere is the innermost layer of the thermosphere. Ionized by solar radiation. Ionosphere is made up of ions. Reflecting radio waves, which allows for long-distance radio communication.

13. Exosphere Exo means outer It is the outer portion of thermosphere Air is extremely thin. Space shuttles and satellites orbit Earth here.