2.  The condition of Earth’s atmosphere at a particular time and place.

3.  The characteristic weather conditions in an area over a long period of time.

4.  We study weather so that we can predict the future. Fun Fact: Ben Franklin made the first recorded weather forecasts in Poor Richard’s Almanac.

5.  Making Observations & Collecting Data ◦ Air Pressure ◦ Temperature ◦ Humidity ◦ Wind Speed & Direction ◦ Precipitation ◦ Cloud Cover

6.  What is it? ◦ The force exerted on you by the weight of the air.  How do we measure it? ◦ Barometer  What unit is it measured in? ◦ US: in (inches of mercury) ◦ Metric: mb (millibars)

7.  What is it? ◦ The measure of how hot or cold the air is.  How do we measure it? ◦ Thermometer  What unit is it measured in? ◦ US: o F (Fahrenheit) ◦ Metric: o C (Celcius)

8.  What is it? ◦ The amount of moisture in the air.  How do we measure it? ◦ hygrometer  Scale used to measure it: ◦ 0% - 100%

9.  What is it? ◦ The measure of how fast the air (wind) is traveling.  How do we measure it? ◦ anemometer  What unit is it measured in? ◦ US: mph (miles per hour) ◦ Metric: km/h ◦ (kilometers per hour)

10.  What is it? ◦ The direction the wind is blowing.  How do we measure it? ◦ Wind vane  What unit is it measured in? ◦ North, South, East, West

11.  What is it? ◦ The amount of precipitation that falls.  How do we measure it? ◦ Rain gauge  What unit is it measured in? ◦ US: in (inches) ◦ Metric: cm (centimeters)

12.  Satellites: Shows cloud cover, warm & cool regions and water vapor.

13.  Radar: Locate clouds and measure their heights. ◦ Doppler: Special radar that can detect air motion & precipitation.

14.  Weather Balloons: Collects data about air at different altitudes (heights).

15.  Ocean Buoys: Measure conditions in the ocean that affect the atmosphere.

16.  Ground Stations: Contain a number of different instruments to collect data in a particular area.

17.  Weather Maps  Diagrams  News Reports  Weather Alerts

18.  The SUN and air.  The sun heats the air around the Earth at different rates, causing wind.