Atmospheric Processes The atmosphere is a protective blanket of gases held in place by the gravitational pull of the earth. It absorbs most of the cosmic rays from outer space and protects living things from their effects. The earth radiates heat that has come from the sun. The atmosphere is essential in maintaining the heat balance on earth. It is our atmosphere which makes earth unique in its ability to support life. The most important layer of the atmosphere is the troposphere which is where the air we breathe and the pollution we produce are found.
Weather is the atmospheric condition that occurs in the troposphere at any particular time in any particular place. Weather affects our lives. Basic weather monitoring involves the observation and measurement of factors such as:
air movement including wind strength, wind direction and air pressure
temperature
rainfall.
The strength of winds and air currents affects how stable the atmosphere is. This in turn determines how high air pollutants are mixed. Atmospheric stability is affected by two processes:
Air heated at the surface rises causing convection. The stronger the heating, the greater the height to which the air is mixed.
Wind blowing over the ground can also cause convection. This is called ‘mechanical convection’ because it is generated as wind encounters obstacles and is forced over and around them.
The amount of convection generated depends on the number and type of obstacles (roughness of the surface) and the strength of the wind.
The atmosphere is a protective blanket of gases held in place by the gravitational pull of the earth. It absorbs most of the cosmic rays from outer space and protects living things from their effects. The earth radiates heat that has come from the sun. The atmosphere is essential in maintaining the heat balance on earth. It is our atmosphere which makes earth unique in its ability to support life. The most important layer of the atmosphere is the troposphere which is where the air we breathe and the pollution we produce are found.
Weather is the atmospheric condition that occurs in the troposphere at any particular time in any particular place. Weather affects our lives. Basic weather monitoring involves the observation and measurement of factors such as:
The strength of winds and air currents affects how stable the atmosphere is. This in turn determines how high air pollutants are mixed. Atmospheric stability is affected by two processes:
- Air heated at the surface rises causing convection. The stronger the heating, the greater the height to which the air is mixed.
- Wind blowing over the ground can also cause convection. This is called ‘mechanical convection’ because it is generated as wind encounters obstacles and is forced over and around them.
The amount of convection generated depends on the number and type of obstacles (roughness of the surface) and the strength of the wind.