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Definition
| Tiny Solid and liquid particles suspended in the atmosphere. |
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Definition
| A mixture of many discrete gases, of which nitrogen and oxygen are most abundant, in which varying quantities of tiny solid and liquid particles are suspended. |
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Definition
| The reflectivity of a substance, usually expressed as a percentage of the incident radiation reflected. |
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Definition
| The equinox that occurs on Sept. 21 -23 in the Northern Hemisphere and on march 21-22 in the Southern Hemisphere. |
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Definition
| The great circle that seperates daylight from darkness. |
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Definition
| A description of aggergate weather conditions; the sum of all statistical weather information that helps describe a place or region. |
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Definition
| The transfer of heat through matter by molecular activity. Energy is transferred through collisions from one molecule to another. |
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Definition
| The transfer of heat by the movement of a mass or substance. It can take place only in fluids. |
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Definition
| Solar energy scattered and reflected in the atmosphere that reaches Earth's surface in the form of diffuse blue light from the sky. |
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Term
| Electromagnetic Radiation (Radiation) |
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Definition
| The transfer of energy (heat) through space by electromagnetic waves. |
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Term
| Element (of weather and climate) |
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Definition
| A substance that cannot be decomposed into simpler substances by ordinary chemical or physical means. |
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Definition
| The rate of temperature decrease with increasing height in the troposphere. |
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Definition
| The transmission of short-wave solar radiation by the atmosphere, coupled with the selective absorption of longer-wavelength terrestrial radiation, especially by water vapor and carbon dioxide. |
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Definition
| The kinetic energy of random molecular motion. |
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Definition
| The tilt of Earth's axis from the perpendicular to the plane of Earth's orbit. |
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Definition
| Radiation with a wavelength from 0.7 to 200 micrometers. |
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Definition
| Lines connecting points of equal temperature. |
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Definition
| The layer of the atmosphere immediately above the stratosphere and characterized by decreasing temperatures with height. |
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Definition
| A molecule of oxygen containing three oxygen atoms. |
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Definition
| The transfer of energy (heat) through space by electromagnetic waves. |
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Definition
| The process whereby light bounces back from an object at the same angle at which it encounters a surface and with the same intensity. |
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Definition
| The motion of one body about another, as Earth about the Sun. |
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Definition
| The spinning of a body, such as Earth, about its axis. |
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Definition
| The redirecting (in all directions) of light by small particles and gas molecules in the atmosphere. The result is diffused light. |
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Definition
| The equinox that occurs on March 21-22 in the Northern Hemisphere and on Sept. 21-23 in the Southern Hemisphere. |
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Definition
| The layer of the atmosphere immediately above the troposphere, characterized by increasing temperatures with height, owing to the concentration of ozone. |
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Definition
| The solstice that occurs on June 21-22 in the Northern Hemisphere and on December 21-22 in the Southern Hemisohere. |
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Definition
| A measure of the degree of hotness or coldness of a substance; a measure of the average kinetic energy of individual atoms or molecules in a substance. |
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Definition
| The region of the atmosphere immediately above the mesosphere and characterized by increasing temperatures due to absorption of very shortwave solar energy by oxygen. |
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Definition
| The parallel of latitude, 23 1/2 degrees south latitude, marking the northern limit of the Sun's verticle rays. |
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Definition
| The parallel of latitude, 23 1/2 degrees south latitude, marking the southern limit of the Sun's verticle rays. |
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Definition
| The lowermost layer of the atmosphere. It is generally characterized by a decrease in temperature with height. |
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Definition
| Radiation with a wavelength from 0.2 to 0.4 micrometer. |
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Definition
| Radiation with a wavelength from 0.4 to 0.7 micrometer. |
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Definition
| The state of the atmosphere at any given time. |
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Definition
| The solstice that ocurs on december 21-22 in the northern hemisphere and on june 21-22 in the southern hemisphere. |
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Definition
| Air that has a lapse rate greater than the dry adiabatic rate. |
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Term
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Definition
| Air with a lapse rate less than the wet adiabatic rate. |
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Term
| Adiabatic Temperature Change |
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Definition
| Cooling or warming of air caused when air is allowed to expand or is compressed, not because heat is added or subtracted. |
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Definition
| A fog formed when warm, moist air is blown over a cool surface. |
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Definition
| A theory that relates the formation of precipitation to supercooled clouds, freezing nuclei, and the different saturation levels of ice and liquid water. |
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Definition
| The amount of heat required to raise the temperature of one gram of water 1*C. |
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Definition
| One of three basic cloud forms; also one of three high cloud types. They are thin, delicate ice-crystal clouds often appearing as veil-like patches or thin, wispy fibers. |
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Definition
| A form of condensation best described as a dense concentration of suspended water droplets or tiny ice crystals. |
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Term
| Cloud of Verticle Development |
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Definition
| A cloud that has its base in the low-height range but extends upward into the middle or high altitudes. |
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Term
| Collision-Coalescence Process |
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Definition
| A theory of raindrop formation in warm clouds (above 0*C) in which large cloud droplets (giants) collide and join together with smaller droplets to form a raindrop. Opposite electrical charges may bind the cloud droplets together. |
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Definition
| The change of state from a gas to a liquid. |
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Definition
| Tiny bits of particular matter that serve as surfaces on which water vapor condenses. |
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Definition
| Moist air with a lapse rate between the dry and wet adiabatic rates. |
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Definition
| The condition that exists when the distribution of winds within a given area results in a net horizontal inflow lower levels is associated with an upward movement of air, areas of convergent winds are regions favorable to cloud formation and precipitation. |
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Term
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Definition
| 1 of 3 basic cloud forms; also the name given one of the cloudsof vertical development. ____ are billowy individual cloud masses that often have flat bases. |
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Definition
| The process by which water vapor is changed directly to a solid without passing through the liquid state. |
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Definition
| The temperature to which air has to be cooled in order to reach saturation. |
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Definition
| The rate of adiabatic cooling or warming in unsaturated air. The rate of temperature change is 1*C per 100 meters. |
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Definition
| The process of converting a liquid to a gas. |
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Definition
| A cloud with its base at or very near Earth's surface. |
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Definition
| Solid particles that serve as cores for the formation of ice crystals. |
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Definition
| The boundary between two adjoining air masses having contrasting characteristics. |
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Definition
| Fog formed when rain evaporates as it falls through a layer of cool air. |
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Term
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Definition
| lifting of air resulting when cool air acts as a barrier over which warmer, lighter air will rise. |
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Definition
| A coating of ice on objects formed when supercooledb rain freezes on contact. |
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Term
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Definition
| Nearly spherical ice pellets having concentric layers and formed by the successive freezing of layers of waters. |
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Term
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Definition
| A cloud that normally has its base above 6,000 meters; the base may be lower in winter and at high-latitude locations. |
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Definition
| A general term referring to water vapor in the air but not to liquid droplets of fog, cloud, or rain. |
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Definition
| An instrument designed to meausure relative humidity. |
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Definition
| Condensation nuclei having a high affinity for water, such as salt particles. |
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Term
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Definition
| The energy absorbed or released during a change in state. |
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Term
| Localized Convective Lifting |
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Definition
| Unequal surface heating that causes localized pockets of air (thermals) to rise because of their buoyancy. |
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Definition
| A cloud that forms below a height of 2,000 meters. |
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Definition
| A cloud occupying the height range from 2,000 to 6,000 meters. |
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Definition
| The mass of water vapor in a unit mass of dry air; commonly expressed as grams of water vapor per kilogram of dry air. |
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Definition
| Mountains acting as bsarriers to the flow of air, forcing the air to ascend. The air cools adiabatically, and clouds and precipitation may result. |
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Term
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Definition
| An imagiinary volume of air enclosed in a thin elastic cover. Typically it is considered to be a few hundred cubic meters in volume and is assumed to act independently of the surrounding air. |
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Term
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Definition
| Fog formed when rain evaporates as it falls through a layer of cool air. |
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Definition
| A device consisting of two thermometers (wet bulb and dry bulb) that is rapidly whirled and, with the use of tables, yields the relative humidity and dew point. |
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Term
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Definition
| Fog resulting from radiation heat loss by Earth. |
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Term
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Definition
| drops of water that fall from a cloud and have a diameter of at least 0.5 millimeter. |
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Definition
| A dry area on the lee side of a mountain range. Many middle-latitude deserts are of this type. |
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Definition
| The ratio of the air's water-vapor content to its water-vapor capacity. |
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Definition
| A thin coating of ice on objects produced when supercooled fog droplets freeze on contact. |
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Definition
| The maximum quantity of water vapor that the air can hold at any given temperature and pressure. |
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Definition
| Frozen or semifrozen rain formed when raindrops freeze as they pass through a layer of cold air. |
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Definition
| A solid form of precipitation produced by sublimination of water vapor. |
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Definition
| Air that resists verticle displacement. If it is lifted, adiabatic cooling will cause its temperature to be lower than the surrounding environment; if it is allowed, it will sink to its original position. |
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Term
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Definition
| Fog having the apperance of steam, produced by evaporation from a warm water surface into the cool air above. |
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Definition
| 1 of 3 basic cloud forms; also, the name given 1 of the flow clouds. They are sheets or layers that cover much or all of the sky. |
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Definition
| The conversion of a solid directly to a gas without passing through the liquid state. |
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Term
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Definition
| The condition of water droplets that remain in the liquid state at temperatures well below 0*C. |
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Definition
| The condition of being more highly concentrated than is normally possible under given temperature and pressure conditions. When describing humidity, it refers to a relative humidity that is greater than 100 percent. |
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Definition
| Air that does not resist vertical displacement. if it is lifted, its temperature will not cool as rapidly as the surrounding environment, so it will continue to rise on its own. |
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Definition
| Fog created when air moves up a slope and cools adiabatically. |
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Definition
| That part of the total atmospheric pressure attributable to water-vapor content. |
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Definition
| The rate of adiabatic temperature change in saturated air. The rate of temperature change is variable, but it is always less than the dry adiabatic rate. |
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Definition
| The force exerted by the weight of a column of air above a given point. |
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Definition
| An instrument for measuring air pressure that consists of evacuated metal chambers very sensitive to variations in air pressure. |
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Definition
| A high-pressure center characterized by a clockwise flow of air in the Northern Hemisphere. |
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Definition
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Term
| Barometric Tendency (Pressure Tendency) |
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Definition
| The nature of the change in atmospheric pressure over the past several hours. It can be a useful aid in short-range weather prediction. |
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Definition
| A wind blowing down the leeward side of a mountain and warming by compression. |
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Term
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Definition
| The condition that exists when the distribution of winds within a given area results in a net horizontal inflow lower levels is associated with an upward movement of air, areas of convergent winds are regions favorable to cloud formation and precipitation. |
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Term
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Definition
| The deflective force of Earth's rotation on all free-moving objects, including the atmosphere and oceans. Deflection is to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. |
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Definition
| A circulation pattern characterized by a light wind blowing into a city from the surrounding countryside. It is best developed on clear and otherwise calm nights when the urban heat island is most pronounced. |
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Term
| Cup Anemometer (Anemometer) |
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Definition
| An instrument used to determine wind speed. |
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Definition
| A low-pressure center characterized by a counterclockwise flow of air in the Northern Hemisphere. |
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Term
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Definition
| The condition that exists when the distribution of winds within a given area results in a net horizontal outflow of air from the region. In ____ at lower levels the resultign deficit is compensated for by a downward movement of air from aloft; hence, areas of __ winds are unfavorable to cloud formation and precipitation. |
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Definition
| The name given to the periodic warming of the ocean that occurs in the central and eastern pacific. A major ____ episode can cause extreme weather in many parts of the world. |
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Definition
| A belt of low pressure lying near the equator and between the subtropical highs. |
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Definition
| A wind, usually above a height of 600 meters (2,000 feet), that blows parallel to the isobars. |
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Definition
| A center of high pressure characterized by anticyclonic winds. |
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Definition
| A line drawn on a map connecting points of equal atmospheric pressure, usually corrected to sea level. |
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Definition
| Swift (120-240 Kilometers per hour), high-altitude winds. |
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Definition
| A local wind blowing from land toward the water during the night in coastal areas. |
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Definition
| An episode of strong trade winds and unusually low sea-surface temperatures in the central and eastern Pacific. Opposite of El Nino. |
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Definition
| A center of low pressure characterized by cyclonic winds. |
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Definition
| a mercury-filled glass tube in which the height of the mercury column is a measure of air pressure. |
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Definition
| Seasonal reversal of wind direction associated with large continents, especially Asia. In winter, the wind blows from land to sea; in summer, from sea to land. |
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Definition
| The nightly downslope winds commonly encountered in mountain valleys. |
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Definition
| In the global pattern of prevailing winds, winds that blow from the polar high toward the subpolar low. These winds, however, should not be thought of as persistent winds, such as the trade winds. |
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Definition
| The stormy frontal zone seperating air masses of polar origin from air masses of tropical origin. |
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Definition
| Anticyclones that are assumed to occupy the inner polar regions and are believed to be thermally induced, at least in part. |
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Definition
| The amount of pressure change occuring over a given distance. |
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Definition
| The nature of the change an atmospheric pressure over the past several hours. it can be a useful aid in short-range weather prediction. |
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Definition
| A wind that consistently blows from one direction more than from another. |
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Definition
| The local name given a chinook wind in southern California. |
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Definition
| A local wind blowing from the sea during the afternoon in coastal areas. |
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Definition
| The seesaw pattern of atmospheric pressure between the eastern and western pacific. |
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Definition
| Low pressure located at about the latitudes of the Arctic and Antarctic circles. In the Northern Hemisphere the low takes the form of individual oceanic cells; in the Southern Hemisphere there is a deep and continous trough of low pressure. |
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Definition
| Not a continous belt of hifh pressure but rather several semipermanent, anticyclonic centers characterized by subsidence and divergence located roughly between latitudes 25 and 35 degrees. |
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Definition
| Two belts of winds that blow almost constantly from easterly directions and are located on the equatorward sides of the subtropical highs. |
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Definition
| The daily upslope winds commonly encountered in a mountain valley. |
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Definition
| The dominant west-to-east motion of the atmosphere that characterizes the regions on the poleward side of the subtropical highs. |
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Definition
| Air flowing horizontally with respect to Earth's surface. |
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Definition
| An instrument used to determine wind direction. |
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