Physical Geography

FACTORS THAT AFFECT CLIMATE 00px-The_Earth_seen_from_Apollo_17.jpg LACEMOPS

Weather – The daily condition of the atmosphere The daily condition of the atmosphere which includes temperature & precipitation Precipitation - Moisture that falls from the sky 4 forms: rain, snow, sleet, & hail Climate - Average weather-over an extended period of time (usually 30 years)

L - LATITUDE - The most important factor! farther from the Equator - the colder & drier The farther from the Equator - the colder & drier it becomes. Direct rays of the sun are always between the Tropics. Areas not in the tropics receive indirect sun rays.

A - AIR MASSES Northern Hemisphere cold air from the Polar Regions comes from the north Northern Hemisphere, cold air from the Polar Regions comes from the north Hot air from the tropics comes from the south Hot air from the tropics comes from the south Mountains to the north of a city could block the cold air from reaching the city (Opposite in the Southern Hemisphere)

C - CONTINENTALITY Water moderates climate. Water takes longer to heat and cool than land. Areas inland from the coast will be hotter in the summer and colder in the winter than areas with the same latitude on the coast NED500.jpg&imgrefurl= %2BNED%2BShaded%2BRelief&h=353&w=500&sz=121&hl=en&start=17&um=1&tbnid=tsJBVC5mQRiZ6M:&tbnh=92&tbnw=130&prev=/images%3Fq%3Dunited%2Bstates%2B%26svnum%3D10%26 um%3D1%26hl%3Den%26safe%3Dactive%26rls%3Dcom.microsoft:en-us:IE-SearchBox%26rlz%3D1I7GGLG%26sa%3DG

E - ELEVATION colder as you go up a mountain Temperature decreases 3.5º F for every 1,000 feet increase in elevation E - ELEVATION It gets colder as you go up a mountain. The formula for vertical climate is: Temperature decreases 3.5º F for every 1,000 feet increase in elevation (the opposite is also true). You can work out the temperature at the top of a tall mountain. sitem.php%3Fid%3D1050&h=300&w=400&sz=22&hl=en&start=6&um=1&tbnid=ODjU- A29uyNbXM:&tbnh=93&tbnw=124&prev=/images%3Fq%3Dmt%2Beverest%26svnum%3D10%26um%3D1%26hl%3Den%26safe%3Dactive%26rl s%3DGGLG,GGLG: ,GGLG:en

3.5° (from formula) 3.5° (from formula) X 15 (how many thousands of feet the mountain is tall) X 15 (how many thousands of feet the mountain is tall) 52.5° (how much colder at the top than the bottom) 52.5° (how much colder at the top than the bottom) It is 75º at the base of a 15,000 ft. tall mountain. What is the temperature on top of the mountain? First, count the thousands… (15,000) 75° (temperature at bottom) 75° (temperature at bottom) ° (how much colder at the top) ° (how much colder at the top) 22.5 ° (temperature at the top)  Answer 22.5 ° (temperature at the top)  Answer Second, multiply that number by 3.5… Third, Subtract that number from the temperature at the base to get the answer…

M - MOUNTAIN BARRIERS Orographic effect: side of a mountain (facing the wind) Wind containing moisture hits the windward side of a mountain (facing the wind) Moisture-full clouds are too heavy to get over the mountain so precipitation occurs, after they’re empty, they are able to rise over the mountain. side facing away from the wind- leeward side The side facing away from the wind- leeward side. windward side -lush vegetation The windward side -lush vegetation leeward sideusually a desert The leeward side-usually a desert

O - OCEAN CURRENTS Cold currents bring dry, cool air to the coastal areas. Warm currents bring warm, wet air to coastal areas.

P - PRESSURE AND PREVAILING WINDS: Notice that these lines are located at 0, 30, 60, 90 (not 0, 23 ½, 66 ½, and 90) Pressure High pressure is heavy, cold air. Low pressure is warm, light air. Heat rises. There are some fairly constant air pressure systems.

Prevailing Winds The Equator is surrounded by an area of calm called the Doldrums (ITCZ). The Trade Winds (Tropical Easterlies) blow from east to west (warm & moist). Westerlies (Prevailing Westerlies) blow from west to east. Polar Easterlies blow from 90º The Polar Easterlies blow from 90º in an eastward direction toward the Westerlies. There are serious thunderstorms around 60º latitude where the 2 wind patterns collide Notice that these lines are located at 0, 30, 60, 90 (not 0, 23 ½, 66 ½, and 90)

S - STORMS Where the Polar Easterlies meet the Westerlies there are thunderstorms. When hot air masses and cold air masses collide - there are storms. Cyclonic storms (hurricanes, typhoons, etc.) in the Northern Hemisphere spin counter-clockwise In the Southern Hemisphere cyclones spin clockwise.