Explanation:

Temperature inversion, is a reversal of the normal behavior of temperature in the troposphere, in which a layer of cool air at the surface is overlain by a layer of warmer air. (Under normal conditions, temperature usually decreases with height). It is called ‘normal lapse rate’. At times, the situation is reversed and the normal lapse rate is inverted. It is called ‘Inversion of temperature’. Inversion is usually of short duration but quite common nonetheless.
Statement 1 is correct. Ideal conditions for temperature inversion:
? Long nights, so that the outgoing radiation is greater than the incoming radiation.
? Clear skies, which allow unobstructed escape of radiation.
? Calm and stable air, so that there is no vertical mixing at lower levels.
Statement 2 is correct. Due to the presence of the above conditions over the polar areas, temperature inversion is normal throughout the year.

Effects of Temperature inversion:
? Inversions play an important role in determining cloud forms, precipitation, and visibility.
? An inversion acts as a cap on the upward movement of air from the layers below. As a result, convection produced by the heating of air from below is limited to levels below the inversion. Diffusion of dust, smoke, and other air pollutants is likewise limited.
? In regions where a pronounced low-level inversion is present, convective clouds cannot grow high enough to produce showers.
? Inversions also affect diurnal variations in temperature. Diurnal variations tend to be very small.
? Less rainfall due to stable conditions.
? Due to inversion of temperature, air pollutants such as dust particles and smoke do not disperse in the valley bottoms. Because of these factors, houses and farms in intermontane valleys are usually situated along the upper slopes, avoiding the cold and foggy valley bottoms. For instance, coffee growers of Brazil and apple growers and hoteliers of mountain states of Himalayas in India avoid lower slopes