Chapter 19 - Air Pressure and Wind

air pressure
Click the card to flip 👆
1 / 17
Terms in this set (17)
air pressure
the pressure caused by the weight of a column of air pushing down on an area
Image: air pressure
Barometer
a device used for measuring air pressure
Image: Barometer
Isobars
a line on a map connecting points having the same atmospheric pressure at a given time or on average over a given period.
Image: Isobars
Pressure Gradient
the spacing of isobars indicates changes in air pressure.
Image: Pressure Gradient
Coriolis Effect
describes how the Earth's rotation affects moving objects (wind, water, airplanes). Objects are deflected to the right in the Northern Hemisphere and to the left in the Southern Hemisphere.
Image: Coriolis Effect
Jet stream
a narrow, variable band of very strong, predominantly westerly air currents encircling the globe several miles above the earth.
Image: Jet stream
Cyclone
center of low pressure - isobars increase in pressure as you move away from the center - bad weather
Image: Cyclone
Anticyclone
center of high pressure - isobars decrease in pressure as you move away from the center - fair weather
Image: Anticyclone
Tradewinds
blow from the east in both hemispheres
NE Tradewinds - 0 degrees N - 30 degrees N
SE Tradewinds - 0 degrees S - 30 degrees S
Image: Tradewinds
Westerlies
blow from the west in both hemispheres
SWesterlies - 30oN - 60oN
NWesterlies - 30oS - 60oS
Image: Westerlies
Polar Easterlieswinds that plow from the polar high toward the subpolar low N Polar Easterlies - 60oN - 90oN S Polar Easterlies - 60oS - 90oSPolar FrontInteraction of warm and cool air masses that produces a stormy belt in the middle latitudesMonsoona seasonal prevailing wind in the region of South and Southeast Asia, blowing from the southwest between May and September and bringing rain (the wet monsoon ), or from the northeast between October and April (the dry monsoon ).Prevailing winda wind from the direction that is predominant at a particular place or season.Anemometeran instrument for measuring the speed of the wind, or of any current of gas.El Niñoin intervals of 3-7 years, this warm countercurrent becomes unusually strong and replaces normally cold offshore waters with warm equatorial waters.La Niñaan atmospheric phenomenon that occurs when colder than normal air blows over the Pacific Northwest