Agrometeorology PDF

# AGROMETEOROLOGY ## Warm cloud seeding - Requires hygroscopic (water attracting) molecules such as common salt (NaCl), urea and ammonium nitrate. - Coalescence process is responsible for the growth of rain drops in a warm cloud. - ABC (Indian Ocean Brown Cloud) - According UNEP the ABC is a blank...

# AGROMETEOROLOGY ## Warm cloud seeding - Requires hygroscopic (water attracting) molecules such as common salt (NaCl), urea and ammonium nitrate. - Coalescence process is responsible for the growth of rain drops in a warm cloud. - ABC (Indian Ocean Brown Cloud) - According UNEP the ABC is a blanket of pollution, stretching across South Asia, which is damaging agriculture and modifying rainfall patterns including monsoon and human being. ## PRECIPITATION - Condensation: Change of vapor form of water to liquid form. - Front: An interface between two air masses. When a cold air mass and warm air mass comes together, warmer one is lifted over colder one with the formation of the front. - Anticyclone: High-pressure area in the center with clockwise circulation in the northern hemisphere. - Cyclone: Low pressure in the center with circular wind motion, i.e., anticlockwise in the northern hemisphere. | Cyclone | Location | |------------|-------------------------------------------------| | Willy willy | Australia | | Hurricane | North- America (i.e., USA), Eastern North Pacific and North Atlantic oceans | | Typhoon | Southeast Asia, Philippines & Western Pacific | | Baguio | China sea | ## Forms of Precipitation | Form of Precipitation | Characteristics | |----------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | Rain | 0.5-7 mm drop diameter | | Drizzle | 0.2 to 0.5 mm drop diameter | | Snow | Ice crystal resulting from sublimation | | Dew | Moisture condensed in small drops upon cool surface, deposits on grass cover, leaves, paper pieces, window, etc. in early morning, it is beneficial to dryland winter crops, forms when condensation occurs on cold objects above freezing points | | Frost | A feathery or thin deposit of ice, forms due to sublimation of water vapor when air temperature falls below freezing point, not frozen dew, forms when condensation occurs below freezing points and change from water vapour to ice. | | Fog | A thin cloud of varying size, small droplets of water condensed in air near the ground to reduce horizontal visibility, formed when the air near the ground falls below dew point temperature, calm wind and RH is over 75%, diameter of particles forming fog is 0.01 to 0.1 mm | | Smog | Blend of fog and smoke, common in cities and industrial areas | | Mist | A very thin fog, wet hygroscopic particles suspended in air |