Climate

1. Climate Chapter 14.1

2. What is climate? • Climatology = the study of Earth’s climate and the factors that affect past, present, and future climatic changes.

3. Climate: more than just average weather

4. Climate The long term weather patterns of an area It describes the annual variations of temperature, precipitation, wind, and other weather variables.

5. Normals • The data that is gathered by meteorologists is averaged on a monthly or annual basis for a period of at least 30 years to determine the “NORMALS” or standard values for a location.

6. Turn your book to pg. 360 • Look at the Problem-Solving Lab • Look at the “Analysis” section and answer the questions to numbers 1 & 2.

7. What causes Climates? • 3 things: • Latitude • Topographic Effects • Air Masses

8. Latitude • Remember: Different parts of Earth receive different amounts of solar radiation. • The amount of solar radiation received by any one place varies because Earth is tilted on its axis, and this affects how the Sun’s rays strike Earth’s surface. • Look at pg. 362 Figure 14-2 • Notice the tropics, temperate zones, and polar zones!

10. Topographic Effects • Water heats up and cools down more slowly than land. • Thus.. Large bodies of water affect the climates of coastal areas. • Many coastal areas are warmer in the winter and cooler in the summer than inland areas of similar latitude.

11. Topographic Effects Continued… • Also temperatures in the lower atmosphere generally decrease with altitude. • Thus, mountain climates are usually cooler than those at sea level.

12. Topographic Effect Continued…. • Climates also differ on either side of a mountain. • Air rises up on one side of a mountain (windward side) as a result of orographic lifting causing precipitation. • The climate on the other side of the mountain (the leeward side) is dry and warm.

13. Air Masses • Two of the main causes of weather are the movement and interaction of air masses.

14. Climate Classification Chapter 14.2

15. Koeppen Classification System • Classification system used for climates. • Uses temperature, precipitation, and vegetation criteria to determine types of climates. • The system is based on the average monthly values of these 3 things.

16. Koeppen found 6 main divisions of climates • Tropical • Dry • Mild • Continental • Polar • High Elevation

17. Tropical Climates • Constant high temperatures • Lots of rain • Tropical rain forests due to heat and rain

18. Dry Climates • Cover 30% of Earth’s land area • Makes up the largest climactic zone • Precipitation is low • Vegetation is scarce • High rates of evaporation • Few clouds • 2 types: • Arid • Semi-arid or steppe. Steppes are more humid than deserts. They usually separate areas of arid regions and wet climates.

20. Mild Climates • Classified into 3 types: • Humid subtropical- warm, muggy weather in summer and cool, dry in winter • Marine west coast- mild winters and cool summers with lots of precipitation throughout the year. • Mediterranean- Summers are warm

21. Marine west coast climate covered in fog. San Francisco: Golden Gate Bridge

22. Continental Climate • 3 subtypes: • Warm summer • Cool summer • Subarctic *** Continental Climates are battlegrounds for clashing tropical and polar air masses.

23. Polar Climates • Coldest regions on Earth • Precipitation is low

24. Microclimates • Sometimes, the climate of a small area can be much different from that of the larger area surround it. • A localized climate that differs from the main regional climate is called a MICROCLIMATE.

25. Heat Islands • The presence of many concrete buildings and large expanses of asphalt can create “heat islands” wherein the climate is warmer than in surrounding rural areas.