1. Warm-Up In which direction does Heat transfer? –Warm to cold What is the main process for heat transfer on earth? –Convection What is the difference between reflection and scattering? –Reflection produces a single output while scattering produces many.

2. Temperature Controls Chapter 17, Section 3

3. Why Temperatures Vary A temperature control is any factor that causes temperature to vary from place to place and from time to time Because variations in the angle of the sun’s rays and length of daylight depend on latitude, they are responsible for warmer temperatures in the tropics and colder temperatures toward the poles Factors other than latitude that exert a strong influence on temperature include heating of land and water, altitude, geographic position, cloud cover, and ocean currents

4. Land and Water Land heats more rapidly and to higher temperatures than water Land also cools more rapidly and to lower temperatures than water Temperature variations, therefore, are considerably greater over land than over water The Southern Hemisphere shows smaller annual temperature variations, due to it having more water than the Northern Hemisphere

5. Mean Monthly Temperatures for Vancouver and Winnipeg

6. Variation in Annual Mean Temperature Range with Latitude

7. Geographic Position A coastal location where prevailing winds blow from the ocean onto the shore (a windward coast) experiences considerably different temperatures than does a coastal location where the prevailing winds blow from the land to the ocean (a leeward coast) The windward coast will experience all of the moderating effects of the ocean, cool summers and mild winters The leeward coast will have a more continental pattern because winds do not carry the ocean’s influence to shore Mountains may act as a barrier for a windward coast, and the opposite side will not receive the moderating effect of the ocean

8. Monthly Temperatures for Eureka, CA and New York City

9. Monthly Temperatures for Seattle and Spokane, WA

10. Monthly Temperatures for Quito and Guayaquil, Ecuador

11. Altitude, Cloud Cover and Albedo Two cities at the same latitude may have much different temperatures due to altitude, with the higher city’s temperature being colder Albedo – the fraction of total radiation that is reflected by any surface Many clouds have a high albedo, and therefore reflect a significant portion of the sunlight that strikes them back to space During the day, clouds will keep the temperatures cooler by not allowing as much solar energy to get through During the night, clouds act as a blanket by absorbing outgoing radiation and reradiating it back to the surface The effect of cloud cover is to reduce the daily temperature range

13. Clouds Reduce Daily Temperature Range

14. World Distribution of Temperature Isotherms – lines that connect points that have the same temperature The isotherms on a world isothermal map generally trend east and west and show a decrease in temperatures from the tropics toward the poles

15. World Distribution of Mean Temperature for January

16. World Distribution of Mean Temperature for July

17. Assignment Read Chapter 17, Section 3 (pg. 488 – 493) Do Section 17.3 Assessment #1-6 (pg. 493) STUDY for Chapter 17 Quiz on MONDAY!