| A | B |
|---|
| Weather | The condition of the Earth’s atmosphere at a particular time and place. |
| Climate | The average, year-after-year conditions of temperature, precipitation, winds, and clouds in an area. |
| Atmosphere | The layer of gases that surrounds Earth |
| Air Pressure | A force that is the result of the weight of a column of air pushing down on an area. |
| Barometer | An instrument used to measure changes in air pressure. |
| Temperature | The average amount of energy of motion in the molecules of a substance. |
| Electromagnetic Waves | A form of energy that can travel through space. |
| Radiation | The direct transfer of energy by electromagnetic waves. |
| Troposphere | The lowest layer of Earth’s atmosphere, where weather occurs. |
| Conduction | The direct transfer of heat from one substance to another substance that it is touching. |
| Convection | The transfer of heat by the movement of a fluid. |
| Wind | The horizontal movement of air from an area of high pressure to an area of lower pressure. |
| Anemometer | An instrument used to measure wind speed. |
| Local Winds | Winds that blow over short distances |
| Coriolis effect | Earth’s rotation makes winds curve |
| Humidity | A measure of the amount of water vapor in the air. |
| Relative Humidity | The percentage of water vapor in the air compared to the maximum amount the air could hold at a certain temperature. |
| Psychrometer | An instrument used to measure relative humidity, consisting of a wet-bulb thermometer and a dry-bulb thermometer |
| Cumulus Clouds | Clouds that look like fluffy, rounded piles of cotton. |
| Stratus Clouds | Clouds that form in flat layers. |
| Cirrus Clouds | Wispy, feathery clouds. |
| Storm | A violent disturbance in the atmosphere. |
| Thunderstorm | Heavy rain storms accompanied by thunder & lightning. |
| Hurricane | A tropical storm that has winds of 119km per hour (74 mph) or higher. |
| Evacuate | Move away temporarily. |
| Flood | Occurs when so much water pours into a stream or river that it overflows its banks and covers the land on either side of the channel |
| Lake-Effect Snow | Forms when cold dry air moves across warm water. When the air reaches land and cools, snow falls. |
| Cyclone | A swirling center of low air pressure. |
| Anti-Cyclone | A high-pressure center of dry air. |
| Front | The area where air masses meet and do not mix. |
