1. Factors Affecting Climate

2. An easy way to remember… O-oceans & currents W-wind patterns E-elevation L-latitude L-landforms

3. LATITUDE LOW LATITUDES MID LATITUDES HIGH LATITUDES

4. Low Latitudes Located between the Tropic of Cancer and Tropic of Capricorn  (23 ½ degrees north to 23 ½ degrees south) Direct sunlight year-round Very warm/hot climates

5. Middle Latitudes Northern Hemisphere: Tropic of Cancer to Arctic Circle Southern Hemisphere: Tropic of Capricorn to Antarctic Circle  (23 ½ degrees N to 66 ½ degrees N)  (23 ½ degrees S to 66 ½ degrees S)

6. Middle Latitudes Summer: Warm air Winter: Cold air Temperate climate-ranges from fairly hot to fairly cold. Weather changes dramatically with seasons

7. High Latitudes Northern Hemisphere: North Pole to Arctic Circle Southern Hemisphere: South Pole to Antarctic Circle  66 ½ degrees N to 90 degrees N  66 ½ degrees S to 90 degrees S Indirect sunlight; cold climate

9. ELEVATION Air temps decrease with elevation For every 1,000 ft increase in elevation, the temp drops by 3 ½ degrees. Example: Quito, Ecuador  Elevation of 9,000 ft.  25 degrees cooler than surrounding areas

10. Wind Wind is caused by differences in air pressure from one place to another.  High pressure always flows into low pressure.  Wind direction always refers to direction wind is blowing FROM. Example: westerlies : wind is coming from the west towards the east.  Why doesn’t wind blow straight?  The Coriolis Effect: the rotation (spinning) of the Earth on its axis causes deflection of the wind.

11. Prevailing Wind Patterns Low latitudes: Easterly Trade Winds  Blow towards equator from 30 degrees N and 30 degrees S Mid-Latitudes: Westerlies High Latitudes: Polar easterlies Equator: Windless area called the doldrums

14. Oceans Areas located by oceans have more uniform temperatures than areas that are deep in the interior of a continent. Why???  Water can mix and distribute heat; land can’t.  Water is slower to heat up/cool down than land.  Marine air/ocean currents regulate the temperatures year- round.

15. Ocean Currents May be warm or cold Either have a cooling effect OR a warming effect on the land they pass Example: Gulf Stream/North Atlantic Drift current warms western Europe – see map on next slide

17. Landforms Orographic Effect: the lifting of an air mass over a large mountain causes a rain shadow on the leeward side of the mountain

21. Example: Rain Shadow in the Sierra Nevada Mtns in the United States

22. The Atacama Desert on the western side of the Andes Mtns is the world’s driest desert. Prevailing winds here are easterlies Prevailing winds here are westerlies

23. Atacama Desert Atacama Desert in Chile (S. America)