Weather objectives 1617 Fronts weather tools clouds convection

Weather objectives 1617 Fronts, weather tools, clouds, convection currents, winds, and severe weather

Objective 16: (Write above your foldable) � I can describe fronts, air masses, pressure systems, weather tools, and clouds

Objective 17: �I can identify weather tools and what they are used for

Thermometers � Bulb Type ◦ Bulb thermometers rely on the simple principle that a liquid changes its volume relative to its temperature

Barometers � Barometer is an instrument used to measure atmospheric pressure in Inches of mercury or millibars. 1 Bar = 1000 m. B � Changes in pressure can forecast short term changes in the weather. � Barographs record longterm changes to identify Low and High pressure system.

Psychrometers Partial Relative Humidity Chart for 30° C � The Difference Between Dry Bulb and Wet Bulb Temperatures simplest hygrometer - a sling None psychrometer - consists 0. 5° of two thermometers mounted together with 1. 0° a handle attached on a 1. 5° 9. 0° chain. One thermometer is ordinary. 9. 5° 14. 5° The other has a cloth 15. 0° wick over its bulb and is 18. 0° called a wet-bulb thermometer. Relative Humidity 100% 96% 93% 89% 44% 42% 19% 17% 5%

Anemometer � Anemometer includes both wind speed and wind direction sensors. � stands up to hurricane-force winds, yet are sensitive to the lightest breeze. � Wind direction vane identifies the direction of the wind ◦ direction is “from” a north wind is from the north

Radar � The Forecast Radar image shows where area of precipitation are expected to be. � colors show the strength and physical phase of water

� THERMOMETER MEASURES AIR TEMPERATURE – � MERCURY BAROMETER – MEASURES AIR PRESSURE � ANEROID BAROMETER – MEASURES AIR PRESSURE

� PSYCHROMETER – MEASURES RELATIVE HUMIDITY � ANAMOMETER/WIND VANE – MEASURES WIND SPEED AND DIRECTION � WEATHER SATELLITES/RADAR – MEASURES CLOUD COVERAGE, AIR MASSES, STORMS, AND FRONTS

Summary � Weather instruments reveal the invisible factors that help predict weather. � Meteorologists use the measurement of Temperature, air pressure, humidity and wind speed/direction to identify weather conditions. � Satellite radar show the movement of air masses, storms and fronts.