Solar Radiation, Heat Balance and Temperature Test - 3

During its revolution around the sun, the earth is farthest from the sun (152 million km) on 4th July. This position of the earth is called aphelion. 

Both Assertion and Reason are true, but Reason is NOT the correct explanation of Assertion.

Because Earth is a sphere, sunlight hits the curved surface more directly closer to the equator and less directly closer to the poles. Solar radiation is most direct at, or close to, the equator and thus produces warmer temperatures.

The amount of heat received by different parts of the earth is not the same. This variation causes pressure differences in the atmosphere. This leads to the transfer of heat from one region to the other by winds.

The fact that the earth’s axis makes an angle of 66½° angle with the plane of its orbit around the sun has a greater influence on the amount of insolation received at different latitudes. 

Smoke and dust particles get collected beneath the inversion layer and spread horizontally to fill the lower strata of the atmosphere.

The energy received by the earth is known as incoming solar radiation which in short is termed as insolation.

The amount and the intensity of insolation vary during a day, in a season and in a year.  The factors that cause these variations in insolation are : (i) the rotation of earth on its axis; (ii)  the angle of inclination of the sun’s rays; (iii) the length of the day; (iv) the transparency of the atmosphere; (v) the configuration of land in terms of its aspect. The last two however, have less influence.

The global distribution of temperature can well be understood by studying the temperature distribution in January and July. The temperature distribution is generally shown on the map with the help of isotherms. The Isotherms are lines joining places having equal temperatures. 

The insolation received by the earth is in short waveforms and heats up its surface. The earth after being heated itself becomes a radiating body and it radiates energy to the atmosphere in the long waveform. This energy heats up the atmosphere from below. This process is known as terrestrial radiation.

The temperature distribution is generally shown on the map with the help of isotherms. The Isotherms are lines joining places having equal temperature.