Weather Factors

How does an object gets its temperature? What takes place to cause the temperature to increase or decrease?

Heat Transfer Thermal energy is the total energy of motion. Temperature is the average amount of energy of motion of each molecule of a substance. Temperature is measured using a thermometer.

How is heat transferred Heat is transferred three ways: Radiation: the direct transfer of energy by electromagnetic waves. Conduction: direct transfer of heat from one substance to another that it is touching. Convection: The transfer of heat by the movement of a fluid.

Wind Wind is the horizontal movement of air from an area of high pressure to an area of lower pressure. All winds are caused by differences in pressure. Wind speed is measured by an anemometer. Local winds are winds that flow over short distances, and global winds are winds that blow in a steady direction over long distances.

Humidity Humidity- is the measure of the amount of water in the air. Relative humidity: the percentage of water vapor in the air compared to the maximum amount the air could hold. Relative humidity is measured by a psychrometer.

Clouds Clouds form when water vapor in the air becomes liquid water or ice crystals. This process is called condensation The temperature at which condensation begins is called the dew point. Clouds form whenever air is cooled to its dew point and particles are present.

Classifying clouds There are three main types of clouds. Cumulus- white puffy clouds less than 2 kilometers above the ground. Stratus- clouds that form flat layers that usually cover most of the sky. Cirrus- Wispy, feathery clouds at high altitudes. nimbus- comes from the Latin word that means “rain”.

Precipitation Precipitation- is any form of water that falls from clouds and reaches Earth’s surface. Common types include: rain, snow, sleet, freezing rain, and hail. Precipitation is measured using a rain gauge.