1. Ch 13: Deserts & Winds Today:

2. “We don’t survive the desert, we live here” we live here” - Pima Indian - Pima Indian “We don’t survive the desert, we live here” - Pima Indian

4. 1) Deserts: where & why Deserts & winds Earth’s dry regions Earth’s dry regions : 30% of all land 2 climate types of dry regions: l desert l desert (arid) l steppe l steppe (semi-arid, surrounds deserts) Question: how much rain do we get in Tempe every year?

5. 1) Deserts: where & why Deserts & winds What causes deserts? l air pressure l wind Important factors: Global distribution of l rainfall l evaporation Relationship between www.weatherchannel.com

6. 1) Deserts: where & why Deserts & winds

7. 1) Deserts: where & why Deserts & winds Low-latitude deserts u Tropic of Cancer u Tropic of Capricorn (recall: “latitude” = east-west line on the globe) u Equator: u hot air u rises to 15-20 km u low pressure belt In contrast….

8. 1) Deserts: where & why Deserts & winds

9. 1) Deserts: where & why Deserts & winds

10. 1) Deserts: where & why Deserts & winds

11. 1) Deserts: where & why Deserts & winds Middle-latitude deserts u exist in rain shadows.

12. 2) Basin and range Deserts & winds Basin and range u mountainous desert landscape

13. 2) Basin and range Deserts & winds Basin and range u mountainous desert landscape

14. 3) Wind erosion/ deposits Deserts & winds Wind erosion: Important in arid environments Example: Types of sand dunes:  Sand dune shape depends on:  Flat or hilly?  How much sand?  Winds steady or intermittent?  Wind direction constant?  Vegetation present?

16. 3) Wind erosion/ deposits Deserts & winds Sand dune formation

17. 3) Wind erosion/ deposits Deserts & winds Desert pavement

18. 3) Wind erosion/ deposits Deserts & winds

20. 3) Wind erosion/ deposits Deserts & winds Graded beds

21. This powerpoint was kindly donated to www.worldofteaching.com www.worldofteaching.com http://www.worldofteaching.comhttp://www.worldofteaching.com is home to over a thousand powerpoints submitted by teachers. This is a completely free site and requires no registration. Please visit and I hope it will help in your teaching.