Friday April 22, 2011

1. FridayApril 22, 2011 (Wind)

2. The Launch Pad Friday, 4/22/11 According to this map, what was the average temperature in the following cities from Feb 25 – Mar 3, 2001? DFW Galveston, Tx Miami, Fl Chicago, Il St. Paul, Mn 50o 60s 70s 30s 10s

3. Announcements Please check your yearly average in this class. If you are below 70 for the year, please come and see me ASAP! There are only two more grades remaining!

5. Wind “Wind” is defined as the horizontalmovement of air. Air moves out of areas of higher pressure into areas of lower pressure. Unequal heating of Earth’s surface generates these pressure differences. Solar radiation, therefore, is the ultimate energy source for most wind. Wind is controlled by a combination of forces, including: the pressure-gradient force the Coriolis effect friction

6. Isobars are lines that connect places of equal air pressure. The spacing of isobars indicates the amount of pressure change over a given distance and is expressed as the “pressure gradient.”

7. Wind The Coriolis effect is also a participant in controlling the wind. This effect is an apparent deflection in the wind direction due to the Earth’s rotation. Deflection of the wind is to the right in the Northern Hemisphere and to the left in the Southern Hemisphere.

8. Wind Finally, friction acts to slow the air’s movement near the surface.

9. Wind Upper level winds generally blow parallel to isobars, and are called geostrophic winds. The Jet Stream is a “river” of air at high altitude with a velocity of 120–240 kilometers per hour.

10. The Geostrophic Wind Figure 18.8

11. Comparison of Upper-Level Winds and Surface Winds

12. Continue Lab Air Masses, the Middle-Latitude Cyclone, and Weather Maps