Chapter 2 Test: Air Pressure and Air Circulation

ITCZ

big, long line of thunderstorm

jet stream

blow from west to east but the flow can shift to north south

subtropic high

cause of many major deserts

friction

causes air to blow across isobars

Global Circulations

causes some places to have semi-permanent lows and highs

weather

changes in the air pressure causes changes to the ___

Santa Anna Winds

chinook style wind - hot, dry, dust bearing winds invade California most often in autumn and bring temps that often exceed 90 degrees

higher

cold air = (higher/lower) pressure

east

cold current: (east/west) side of basin

polar high

cold, dense air sinks - air diverges toward lower latitudes

higher

cold, dry air mass will produce (higher/lower) surface pressure than a warm, humid air mass

eastward

commercial aircraft use jet streams when going (eastward/westward)

low

cyclone: (high/low) pressure

synoptic

cyclones and anticyclones are examples

increase

decrease in pressure with an (increase/decrease) in altitude

coriolis force

deflection of winds caused by rotation of the earth

Coriolis effect

deflection of winds caused by the rotation of the earth

density = mass / volume

density equation

lower

denver has a (higher/lower) pressure than Miami

gradient

difference in pressure over a distance

mountain and valley breeze

during the day, air along mountain slopes is heated more intensely than air in the bottom of a valley - this leads to warm air rising up along the mountain slop and create a valley breeze

same

equatorial low and ITCZ are the ___ thing

microscale

events that have a life span from a few seconds to minutes (wind gusts)

Torricelli's Barometer

found out it was not a vacuum but atmospheric pressure

warm

gas molecules in (warm/cold) air have abundant kinetic energy, and they are more widely spaced (less dense)

temperature imbalance

global circulations are driven by ___

geostropic winds

gradient of pressure and coriolis force coming in to balance

high

gradual pressure gradient = (high/low) pressure system

friction

greatest at earth's surface - different over land and water

strengthened

gulf stream is ___ by prevailing winds

pressure gradient

high pressure air going to low pressure areas

horse latitudes

horse latitudes

Caribbean

in the north atlantic, the equatorial current is deflected northward through the...

macroscale

includes large planetary flow extended around the entire glove and can remain unchanged for weeks at a time (ex: trade winds)

isobar

indicate changes in pressure on a mpa

100kt + wind speed / 10-12km in altitude

jet stream

steep pressure / temp gradient

jet stream happens when there is>>>

mesoscale event

land and sea breezes fall into this category

thermal equator

latitude where noontime sun is directly overhead

isobars

lines connecting equal points of pressure

close

low pressure means isobars are (close/far)

far

low pressure means isobars are (close/far)

single cell model

model invented by George Hadley in 1735 - he was aware that solar energy drives the winds - he proposed the the large temp contrast between the poles and the equator creates one large convective cell in each hemisphere - doesn't take into consideration the earth rotation on its axis

lower

moist air = (higher/lower) pressure

lighter

moist air is (lighter/heavier) than dry air

jet stream

narrow ribbon of high-speed winds that meander for thousands of kilometers

windspeed

pressure gradient force is directly related to __

differ

pressures ___ from place to place

Foehn winds

warm, dry winds sometimes move down the alps

chinook winds

warm, dry winds sometimes move down the east slope of the Rockies

clear skies

weather associated with high pressure...

storms

weather associated with low pressure...

anticyclone

weather system with high atmospheric pressure at center

rises

warm air = volume (rises/falls)

lower

warm ari = (higher/lower) pressure

west

warm current: (east/west) side of basin

loads

(loads/no) precipitation at equator because of ITCZ

right

Coriolis Force makes northern hemisphere go (right/left)

left

Coriolis Force makes the southern hemisphere go (right/left)

subsiding air

___ causes clear skies and warm temps

temp and water vapor content

____ and ___ influence air pressure

30 degrees NS

____ high pressure at subtropical height (explains distribution of precipitation)

synoptic scale

a somewhat smaller macro scale circulation

prevailing winds

a wind from the direction that is predominant at a particular place or season

out

air moves (out/in) from high pressure areas

in

air moves (out/in) low pressure areas

high / low

air moves from (high/low) pressure to (high/low) pressure

proportional

air pressure is ___ to density

high

anticyclone: (high/low) pressure

high

areas of (high/low) pressure are formed when air is sinking back down, and so pushing down harder on the surface

ITCZ

around the equator =

pressure

as the density of a column of air increases, so does the ___ it exerts on the surface

mesoscale

associated with local winds that generally last from minutes to hours (tornadoes)

10mb / 100m

average rate of change used to adjust pressures for all locations to sea-level pressure values

falls

volume increases = density (rises/falls)

subpolar low

responsive for much of the stormy weather in the middle latitudes, particularly in the winter

thunderstorm

rising air promotes ___ development

subtropical high

sinking air in the subtropics piles up and must diverge

microscale events

smallest scale of air motion - chaotic winds that normally last for a few seconds and at most most minutes (ex: gusts, dust devils)

trade winds

some air flows northward, some flows southward to create ___

1013.25mb = 1013.25hPa = 29.92in

standard sea level pressure

low

steep pressure gradient = (high/low) pressure system

pressure gradient force

system want to return to equilibrium - thus air moves from high pressure to low pressure

land and sea breeze

the daily temp contrast between land and the sea and the pressure pattern generates this

mountainous regions

the fact that density decreases with altitude is why the term "thin air" is normally associated with ___

mesoscale events

these systems are always embedded within and his move as part of the larger macro scale circulation

air moves from high pressure to low pressure

this is how winds are formed

intertropical convergence zone

trade wind convergence

Coriolis Force

turning of an object's trajectory due to earth's rotation

single cell model and three cell model

two general circulation models...

millibar

unit of measure for atmospheric pressure

minibars (mb), inches of mercury (in) and hectopascal (hPa)

units of measure for comparing atmospheric pressures

lower

when air rises, it leaves behind an area of (higher/lower) pressure, because the upward-moving air is not pressing down so hard on the surface

thin ribbons of fast moving air occur where the warm subtropical and cool polar air masses meet

where the jet stream occurs

convergence

wind blowing into a region

divergence

wind blowing out of a region

pressure gradient force, Coriolis force, and friction

wind is controlled by...

convergence

winds blowing into a region - air piles up, must begin to flow upward

divergence

winds blowing out of a region - associated with a decrease in pressure

perpendicular

winds move ___ to isobars