19.2 Factors Affecting Winds

The Coriolis Effect The tendency of an object moving freely over Earth’s surface to curve away from its path of travel http://www.williamsclass.com/EighthScienceWork/Atmosphere/AtmosphereWind.htm

Coriolis Effect http://www.youtube.com/watch?v=mcPs_OdQOYU

Greatest near the poles; least near the equator More Coriolis Effect To the right in the Northern Hemisphere; to the left in the Southern Hemisphere Greatest near the poles; least near the equator noaa.gov

The faster the object, the greater the deflection More Coriolis Effect The faster the object, the greater the deflection Not dependent on object’s movement direction http://www.earthlyissues.com/coriolis.htm

More Coriolis Effect The effect is only noticeable for objects traveling over great distances, like an airplane or wind http://www.earthlyissues.com/images/gaspcor.gif

Coriolis Effect on Highs/Lows Wind spirals clockwise out of high pressure; spirals counterclockwise into low pressure in our Hemisphere http://myweb.cwpost.liu.edu/vdivener/ers_1/chap_6.htm

Slows down the air near Earth’s surface Friction Slows down the air near Earth’s surface Force decreases with height, so winds increase with height http://www.school-for-champions.com/science/friction_uses.htm

The Polar-Front Jet Stream Bands of swiftly moving winds near the top of the troposphere Divides cold air to the north, warm air to the south http://www.crystalinks.com/jetstream2.jpg

The Polar-Front Jet Stream Supplies energy to storms and guides their paths Shifts south in winter, north in summer http://www.cuttingedge.org/News/Jetstream_081402.jpg

The Polar-Front Jet Stream Discovered around WWII (1939) Allied bombers arrived early to their targets (tailwind); ground speed was very slow on return trip (headwind)—ran out of fuel http://araeld.deviantart.com/art/Boeing-B29-quot-Enola-Gay-quot-66959878

Review Questions List 3 factors that affect wind direction. Describe the path of air as it travels into a low-pressure area in the Northern Hemisphere. What effect could the polar-front jet stream have on the speed of an airplane flying eastward? An airplane flying westward?