Question

1.How do air temperature and pressure change with height?

Answer 1

Temperature and height are inversely related in the troposphere region ie,lowest 10-20 km of atmosphere , because most of the solar radiation passes through the atmosphere with little or no effect- that radiation is absorbed by the solid earth surface and transferred to the air above the surface by conduction.As conduction is a slow process and it takes long time to transfer that incoming solar energy upward,so the temperature in the troposphere decreases with height.

Above some point ,another processes causes temperature to become nearly constant with height or even to increase with height.This is due to absorption of solar energy by ozone in the stratosphere.This is the main difference between troposphere and stratosphere and this transition in temperature with height is called tropopause.

Pressure also decreases with increasing height.It is because pressure is determined by mass of atmosphere above some point.As height increases ,the amount of atmospheric mass decreases ,so pressure also falls.The decrease in pressure is mainly due to two reasons,both of which are related to gravity.

The gravitational attraction between earth and air molecules is greater for those molecules nearer to earth than those further away dragging them closer together and increasing pressure between them.Also as height increases ,the gravitational attraction is less towards molecules further away from the earth