Atmosphere & Weather

Geography · वायुमंडल और मौसम · 19 facts

Humidity = amount of water vapor in the air. Relative Humidity = actual moisture / capacity x 100%

Atmosphere composition: N2 78%, O2 21%, Argon 0.93%, CO2 0.04%

5 layers bottom to top: Troposphere → Stratosphere → Mesosphere → Thermosphere → Exosphere

All weather and clouds occur in the Troposphere

Ozone layer is in the Stratosphere (20–35 km)

Mesosphere = coldest layer (-90°C), meteors burn here

Ionosphere (in Thermosphere) reflects radio waves

4 pressure belts: Equatorial Low, Subtropical High, Subpolar Low, Polar High

Trade winds: 0–30°, Westerlies: 30–60°, Polar Easterlies: 60–90°

Doldrums = Equatorial calm zone, Horse Latitudes = Subtropical calm zone

Tropical cyclone: Hurricane (Atlantic), Typhoon (Pacific), Cyclone (Indian Ocean)

3 types of rainfall: Convectional, Orographic, Frontal

Rain shadow area = leeward side of a mountain (dry)

Jet streams flow west to east at 9–12 km height

Troposphere temp drops at 6.5°C per km (Normal Lapse Rate)

Coriolis Effect deflects winds to right in NH, left in SH

Weather = short-term atmospheric conditions at a place (hours/days).

Subpolar Low Pressure — 60°–65° N/S — Low pressure — warm and cold air meet, frontal rainfall

Polar High Pressure — 85°–90° N/S — High pressure — extremely cold, descending dry air