Top 50 Q. of Agricultural Meterology

1. The term Meteorology is derived from the Greek word “Meteoron” meaning things in the air.
2. The first Meteorological Observatory in India was established in Madras (1792).
3. The India Meteorological Department (IMD) was established in 1875 with headquarters at Pune (now New Delhi).
4. IMD functions under the Ministry of Earth Sciences.
5. The World Meteorological Organization (WMO) was established in 1950, headquartered in Geneva, Switzerland.
6. WMO replaced the International Meteorological Organization (IMO) which was established in 1873.
7. The World Meteorological Day is celebrated every year on 23rd March.
8. The theme for World Meteorological Day (2025)** changes every year** based on global climate priorities.
9. The normal lapse rate of temperature in the troposphere is 6.5°C per 1000 m rise in height.
10. The average thickness of the troposphere is about 16 km at the equator and 8 km at the poles.

Facts about the Atmosphere

11. The atmosphere extends up to about 1,600 km above the earth.
12. Troposphere contains about 75% of the total mass and 99% of water vapour of the atmosphere.
13. The upper boundary of the troposphere is called the Tropopause.
14. The Stratosphere lies between 10 km to 50 km and contains the Ozone layer.
15. The Ozone layer absorbs most of the ultraviolet (UV) radiation.
16. The Mesosphere lies between 50 km to 80 km altitude.
17. The Thermosphere (Ionosphere) lies between 80 km to 400 km.
18. The Exosphere lies above 400 km and merges gradually into space.
19. The atmosphere consists of 78% Nitrogen, 21% Oxygen, 0.93% Argon, and 0.03% Carbon dioxide.
20. The average atmospheric pressure at sea level is 1013.25 mb (millibar) or 760 mm of Hg.

Solar Radiation and Temperature Facts

21. The solar constant is 1.94 cal cm⁻² min⁻¹ (or 1367 W/m²).
22. The earth receives only one-two billionth of the total solar radiation emitted by the sun.
23. The shortwave radiation from the sun mainly includes visible and ultraviolet rays.
24. The longwave radiation is emitted by the earth’s surface (infrared).
25. The Albedo of earth’s surface is 30–35%.
26. Maximum solar radiation is received at 12 noon.
27. The Earth’s average temperature is about 15°C.
28. The Greenhouse gases (GHGs) include CO₂, CH₄, N₂O, O₃, and water vapour.
29. The CO₂ concentration in the atmosphere is about 0.04% (400 ppm).
30. Carbon dioxide contributes about 60% of total greenhouse effect.

Wind and Pressure Facts

31. Wind is the horizontal movement of air from high pressure to low pressure areas.
32. Anemometer is used to measure wind speed.
33. Wind vane is used to measure wind direction.
34. The Coriolis force causes the deflection of wind to the right in Northern Hemisphere and to the left in Southern Hemisphere.
35. Isobars are the lines joining points of equal pressure on a weather map.
36. Land and sea breezes are examples of local winds.
37. Monsoon is a seasonal reversal of wind direction.
38. The Southwest monsoon in India sets in around June 1 in Kerala.
39. El Niño is the warming of Pacific Ocean waters, affecting Indian monsoon.
40. La Niña is the cooling of Pacific waters, often strengthening Indian monsoon rainfall.

Rainfall and Humidity Facts

41. Rain gauge measures precipitation.
42. Normal annual rainfall in India is about 1180 mm.
43. Highest rainfall in India is recorded at Mawsynram, Meghalaya.
44. Relative humidity is the ratio of actual vapour pressure to saturation vapour pressure, expressed in percentage.
45. Psychrometer and hygrometer are used to measure humidity.
46. Dew point is the temperature at which air becomes saturated.
47. Condensation nuclei are required for the formation of clouds.
48. Nimbostratus and Cumulonimbus are rain-bearing clouds.
49. Hailstorms are associated with Cumulonimbus clouds.
50. Fog is a cloud in contact with the ground surface.