UPSC Notes

Evaporation is the phenomenon in which an individual substance is transformed into gas. It occurs in almost all cases in nature, but during this process, some latent heat is also released, which causes the transformation of water to occur in a continuous manner. Latent heat in vaporisation comes in many forms, but it primarily depends

Water is present in the atmosphere in three forms namely – gaseous, liquid and solid. The moisture in the atmosphere is derived from water bodies through evaporation and from plants through transpiration. Water vapour present in the air is known as humidity. Solid form of water is one which you cannot see with your bare

A thunderstorm is a storm that produces lightning and thunder, and sometimes heavy rain. Due to the lightning and thunder of a passing storm, it is often referred to as a squall line or a lightning storm. Depending on the nature of the lightning, a thunderstorm may be called a thunder and lightning storm or

Since the atmosphere is heated from above by direct solar radiation, it heats the Earth’s surface unevenly. The tropics are hot, but are hotter further south due to proximity to the equator. The extra heat makes the air rise there. The hot air moves away from the equatorial regions, generally northward or southward toward the

Wind is a meteorological phenomenon in which there is a flow of air in the atmosphere, called wind. It happens when the sun heats the ground or ocean or water to a temperature higher than that of adjacent regions. This difference in temperature generates thermal currents, i.e., an uneven heating of the ground and water

Sea level pressure is a measurement that is done in millibars or hectopascals. It is also known as atmospheric pressure. It is the average pressure of the air over a given area. Along 30° N and 30° S are found the high-pressure areas known as the subtropical highs. Further pole wards along 60° N and

Atmospheric pressure is the force exerted on a surface by the weight of air above that surface. The total atmospheric pressure at sea level is the average of the air pressure at the Earth’s surface and the air pressure at sea level. The atmospheric pressure is expressed in units of milibar. At sea level the

Inversion of temperature is a meteorological condition in which a layer of warm air is situated above a layer of cooler air at the same height. This situation affects stability in the atmosphere and restricts the vertical mixing of atmospheric constituents. Inversions occur when warm air is underlain by cool air at the same level,

Temperature is a measure of how hot (or cold) a thing is. We measure temperatures with thermometers to give us the numerical value that we know as temperature. The major units of measuring temperature are Celsius and Fahrenheit. Factors Controlling Temperature Distribution The variations of climate are controlled by the size, shape and altitude of