Weather and Climate

1. Unit 4 Lesson 5 Weather and Climate S8.D.2.1.1-3

2. Weather vs Climate Weather • Is the condition of the atmosphere including temperature, pressure, and humidity at a particular time and place Climate • Is the average weather of an area over a long period of time • Warmer climates exist near equator and colder climates exist near poles

3. Earths Atmosphere Temperature changes and the atmosphere

4. Air Masses • A large body of air that has the same temperature and humidity throughout  the amt of water vapor in the air • air masses take on the characteristics of the area over which they form • over sea (maritime) wet • over land (cont.)  dry • they move in certain directions

5. Air Pressure • Also called Barometric Pressure • Is the weight of the air pushing down on a particular area Pressure system  region of atmosphere that has a similar barometric pressure throughout  Two types • High Pressure System • Low Pressure System

6. High Pressure System • Generally produces clear, dry skies Predicting Weather • If the barometric pressure is rising, a high pressure system is moving in and weather will clear up

7. Low Pressure System • Often brings rain or snow Predicting Weather • If the barometric pressure is dropping, a low pressure system is moving in and weather will become cloudy and rainy/stormy

8. Clouds • When air rises it cools and the water vapor in the air condensed into tiny liquid droplets which make up a cloud • Nimbus • producing precipitation

9. Stratus clouds • associated with overcast days • Cumulus Clouds • puffy white clouds on fair days • Can turn into storm clouds • Cirrus Clouds • high, feather-like clouds associated with clear sunny days

10. Clouds

11. Prevailing Winds • Winds close to the earth’s surface that consistently blow in the same direction • Can affect an area’s climate

12. Effect of Water on Weather • Large bodies of water (oceans) can store large amounts of heat • During Cold Months: If water is warmer than air, heat will move to air, bringing warmer weather to cold areas • During Hot Months: If air is warmer than cool water, heat will move to the water, bringing cooler weather to warm areas

13. Effect of Water on Weather • Because water warms and cools so slowly relative to land and air, areas near large bodies of water tend to have more stable temperatures • Places located near large bodies of water have warmer winters and cooler summers. Myrtle Beach will have warmer winters and cooler summers than Columbia

14. Lake-Effect Snow • Cold arctic air blows over warmer Great lakes • Air close to lake becomes warm and moist and rises • As it rises, water vapor condenses into clouds • As clouds move over opposite shore, they release snow

15. Lake-Effect Snow