Tiêu đề Meteorology Part-2.pdf ✅

www.iaritoppers.in Whatsapp : +91-9694095242 Page | 1 Meteorology 5 th Edition 2024
www.iaritoppers.in Whatsapp : +91-9694095242 Page | 2 Transfer of heat:  All matter, at a temperature above the absolute zero, imparts energy to the surrounding space. Three processes viz. conduction, convection and radiation are involved in heat flow or heat transfer. Conduction:  Heat transfer through matter without the actual movement of the substances or matter. Heat flows from the warmer to cooler part of the body so that the temperatures between them are equalized. Eg. The energy transmission through an iron rod which is made warmer at one end. Convection:  Processes of transmission of heat through actual movement of molecules of the medium. This is predominant form of energy transmission on the earth as all the weather-related processes involve this process. Eg. Boiling of water in a beaker Radiation:  Transfer of energy from one body to another without the aid of the material medium (solid, liquid or gas).  Radiation is not heat, only when radiation is absorbed by surface of a body heat is produced. Eg. The energy transmission through space from the sun to the earth. Latent heat:  A part of the incident radiation on the surface is absorbed, while a part is reflected and the remaining is transmitted.  Latent heat is the energy required to change a substance to a higher state of matter. This same energy is released on the reverse process. Solar constant:  Solar constant is the energy received on a unit area at the outer most boundary of the earth (atmosphere) surface held perpendicular to the sun’s direction, at the mean distance between the sun and the earth.
www.iaritoppers.in Whatsapp : +91-9694095242 Page | 3 Albedo:  It is the percentage of reflected radiation to the incident radiation. High albedo indicates that much of the incident solar radiation is reflected rather than absorbed. Substance Albedo % Substance Albedo % Ice 90% Wheat 23-25 Indian soil 35 Rice 12 Average of earth 30 Potato 19 Meadows 10-20 Pearl Millet 24 Ploughed Soil 14-17 Moong 26 Black dry soil 14 Crop Plant 15-25 Black moist soil 08 Lucerne 23-32 Grey dry soil 25-30 Grey moist soil 10-12 Light:  Light is the visible portion of the solar spectrum with wave length range is from 0.39 to 0.76μ. Based on the response to light intensities, the plants are classified as follows: 1. Sciophytes (shade loving plants): The plants grow better under partially shaded conditions. Eg. Betel vine, buck wheat etc. 2. Heliophytes (Sun loving): Many species of plants produce maximum dry matter under high light intensities when the moisture is available at the optimum level. Eg. Maize, sorghum, rice etc.
www.iaritoppers.in Whatsapp : +91-9694095242 Page | 4 Heat Injuries: Thermal death point:  The temperature at which the plant cell gets killed when the temperature ranges from 50-60°C. Sun clad:  Injury caused on the barks of stem by high temperature during day time and low temperature during the night time. Stem griddle:  The stem at ground level scorches around due to high soil temperature. It causes death of plant by destroying conductive tissues. Cold Injury: 1. Chilling injury:  Plants which are adapted to hot climate, if exposed to low temperature for some time, are found to be killed or severely injured or development of chloratic condition (yellowing) eg. Chloratic bands on the leaves of sugarcane, sorghum and maize in winter months when the night temperature is below 20°C. 2. Freezing injury:  This type of injury is commonly observed in plants of temperate regions. When the plants are exposed to very low temperature, water freezes into ice crystals in the intercellular spaces of plants.  The protoplasm of cell is dehydrated resulting in the death of cells. Eg. Frost damage in potato, tea etc. 3. Suffocation:  In temperate regions, usually during the winter season, the ice or snow forms a thick cover on the soil surface. As a result, the entry of oxygen is prevented and crop suffers for want of oxygen. Ice coming in contact with the root prevents the diffusion of CO2 outside the root