| A | B |
|---|
| Weather | The condition of the atmosphere at a given time and place. |
| meterology | The scientific study of the atmosphere. |
| atmospheric pressure | Weight of atmospheric gases on the earth's surface. |
| wind | Moving air |
| windchill factor | The lowering of felt air temperature as wind blows over unprotected skin. |
| precipitation | In geology, any process that causes chemical substnces dissolved in water to form a solid compound that settles out of solution. |
| humidity | A measure of the amount of gaseous water vapor in the air. |
| relative humidity | A ratio of the amount of water the air is actually holding to the amount it could hold at the same temperature, expressed as a percentage. |
| pressure gradient | The rate of change of atmospheric pressure with horizontal distance. |
| cyclone | A low pressure center toward which surrounded winds spiral counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere. |
| anticyclone | A high pressure center from which winds spiral outward in a clockwise direction in the Northern Hemisphere or counterclockwise in the Southern Hemisphere. |
| trade wind | A reliable global wind blowing from the subtropical highs toward the Equator, deflected toward the west by the Coriolis effect. |
| prevailing westerly | A global wind of the mid latitudes that blows consistently from southwest to northeast. |
| polar easterly | A dense, cold glogal wind spiraling out from the high pressure zones over the poles from the east, angling toward the mid latitudes. |
| dew point | The temperature of a parcel of air at which the relative humidity is 100%. |
| cloud | A mass of extremely tiny liquid water droplets or ice crystals in the atmosphere. |
| condensation nucleus | A microscopic particle suspended in the air on which water easily condenses to form droplets. |
| freezing nucleus | A microscopic particle suspended in the air on which water easily deposits to form ice crystals. |
| fog | Stratus like clouds that form at ground level. |
| coalescence | The process by which droplets join together and grow to form raindrops or hail. |
