lacemops Factors Affecting Climate 1

What’s the Difference? Weather: the daily condition of the atmosphere which includes temperature and precipitation. (think: weather or not to wear a coat today). Climate: average weather over an extended period of time. Precipitation: Moisture that falls from the sky (rain, snow, sleet, hail) 2

Essential Questions What factors affect climate? What is the most important factor? How does climate impact you? 3

Factors Affecting CLimate L atitude A ir Masses C ontinentality E levation M ountain Barriers O cean Currents P ressure and Prevailing Winds S torms 4

L ACEMOPS: Latitude The most important factor Low latitude: high temperature Middle latitude: temperate High latitude: low temperature 5 high middle low middle high

L A CEMOPS: Air Masses Cold air from the polar regions, warm air from the tropics. Air takes on the characteristics of the land or water it passes over. Fronts are the boundaries between air masses of different temperature or moisture levels 6

LA C EMOPS: Continentality Water moderates climate  Water takes longer to cool/heat than land. Places located near large bodies of water have a relatively mild climate. Inland areas have more extreme climates for winter and summer 7 Pacific Ocean

LAC E MOPS: Elevation The higher the elevation, the colder and drier the air. Think: peaks of mountains have snow. 8 The higher the elevation, the colder the temperature. That’s why there are snow-capped mountains on the Equator. For every 1000 feet increase in elevation, the temperature is 3 ½ degrees colder.

LACE M OPS: Mountain Barriers High mountains located near large bodies of water block the moisture that blows in from the ocean and creates a rain shadow on the leeward side of the mountain. Orographic effect: Windward side gets precipitation. Leeward side is dry. Dry side is called a “rain shadow.” 9

Orographic Precipitation 10 Windward side of the Mountain Leeward side of the Mountain Rain Shadow

LACEM O PS: Ocean Currents 11  The movement of the water creates ocean currents, which transport heat energy throughout the biosphere heat back and forth between the tropics and the polar regions.

Irregular Ocean Currents El Niño and La Nina refer to a periodic reversal of the pattern of ocean currents and water temperatures in the mid-Pacific regions. El Nino episodes reflect periods of exceptionally warm sea surface temperatures across the eastern tropical Pacific. La Niña episodes (right hand column) represent periods of below-average sea-surface temperatures across the eastern tropical 12

LACEMO P S: Pressure & Prevailing Winds High Pressure =H Heavy, cool air, brings clear skies and no rain Low Pressure =L Light, warm air, usually brings precipitation 13

LACEMO P S: Pressure & Prevailing Winds  Prevailing winds blow from the same direction: Polar Easterlies (E  W) Westerlies (W  E) Trade winds (E  W) CORIOLIS EFFECT: due to earth’s rotation winds do not blow straight but are bent  Area of no prevailing winds: Doldrums (calm areas around equator) Horse latitude winds (between the westerlies and trade winds, they are an area of calm HILO: winds move from high pressure areas to low pressure areas 14

LACEMOP S : Storms When hot air masses and cold air masses collide - there are storms. Types of storms: Tornadoes: form quickly; relatively small diameter; usually in middle latitudes Hurricanes: ocean storms that cover large areas and take days to form Typhoon: hurricanes in the western Pacific Ocean 15

LACEMOP S : Storms Where the Polar Easterlies meet the Westerlies there are thunderstorms. Cyclonic storms (hurricanes, typhoons, etc.) in the Northern Hemisphere spin counter-clockwise. In the Southern Hemisphere cyclones spin clockwise 16

LACEMOP S : Storms: WHICH HAVE YOU EXPERIENCED? Hurricanes Tornadoes Floods Winter Storms Severe Thunderstorms 17

The End! Make sure you know all the factors affecting climate 18