1. Weather & Climate “Climate is what you expect; weather is what you get”.

2. Rotation & Revolution Earth’s axis tilted 23.5° from perpendicular. Earth rotates on its axis as it revolves around the sun. Earth's Orbit Earth's Orbit

3. Seasons Earth’s tilt & revolution around the sun cause different places to receive varying amounts of sunlight throughout the year.

4. Earth/Sun Relationships Solstices- days when the sun‘s direct rays fall at the Tropics of Cancer & Capricorn Summer= Jun. 21; Winter= Dec. 21

5. Earth/Sun Relationships Equinoxes- markers for seasonal change The sun’s direct rays fall at the Equator. Spring= Mar. 21; Fall= Sep. 23

6. Greenhouse Effect The trapping of the sun’s energy by the earth’s atmosphere in the form of heat. Caused by Carbon Dioxide (CO 2 )& other greenhouse gases. Weather- daily conditions of the bottom layer of the earth’s atmosphere.

7. Atmospheric (Barometric) Pressure- The weight of the atmosphere overhead Rising warm air creates low pressure & stormy weather. Sinking cool air causes high pressure & clear weather. Winds are named from where the originate.

8. Precipitation Any form of water that falls to the Earth's surface. Occurs when warm air cools & water vapor condenses to form water droplets. Depending on conditions it can fall as rain, snow, sleet, or hail.

9. Convectional Precipitation Heating of the earth's surface causes air to rise rapidly. As the air rises, it cools & water vapor condenses into droplets. Common near the Equator & during summer at higher latitudes.

10. Orographic Precipitation Warm moist air is forced to rise over a high landform. Air mass cools as it rises, water vapor condenses, & precipitation results on the windward side. Warming, dry air on the leeward side picks up excess moisture causing a rainshadow. Common along seacoasts. windward

11. Frontal Precipitation Results when the leading edge (front) of a warm air mass meets a cool air mass. A warmer air mass is forced up over cooler air. Warm air cools as it rises, water vapor condenses, & precipitation forms. The most common type of precipitation.