geography test 2
cirrus
"lock of hair"- wispy, feathery, high clouds, composed of ice crystals, cirriform
hurricanes
- tropical cyclones. features: low pressure, no fronts, 100- 600 miles across, pressure 950 mb or lower, winds 65 knots +, winds counterclockwise in the NH, center of the storm is an eye. The eye is calm and has highest winds in the eye wall. -develop over tropical oceans -energy source is latent heat - conditions necessary: warm sea water and deflection of winds by the coriolis effect -move west with trade winds -source of damage:storm surge, high winds, flooding inland
H- Highline climate
-usually cool- tempertures decrease with altitude -usually moist- oropgraphic precipitation
cP
Continental Polar-northern canada, cold and dry
land/sea breeze-How is each generated, and what effects does each have on the weather?
Land Breezes - Winds from the Land --> Sea Sea Breezes - Wind from Sea --> Land
Pressure gradient
Pressure gradient is how much the atmospheric pressure lowers in an area at a specific time.
polar front
The region or boundary separating air masses of cold polar origin from those of warm tropical or subtropical origins.
ET
Tundra climate; very cold, no month over 50 degrees F, 1 month is over freezing, tundra vegetation there are no trees, boundary between D/E climates is the TREELINE
Chinook-How is each generated, and what effects does each have on the weather?
Warm downslope winds
relative humidity
a ratio. RH= actual water vapor content/ water vapor content at saturation or actual mixing ratio/ saturation mixing ratio
Subtropical highs
a significant belt of high pressure situated around the latitudes of 30°N in the Northern Hemisphere and 30°S in the Southern Hemisphere.
warm front
a warm air mass invades a mass of colder air -gentle slope -moves slowly -leading edge above ground -gentle prolonged precipitation -stratus and nimbostratus -symbol is a line with half circles pointing in direction the warm air is moving
humidity
amount of water vapor in the air
air masses:
cP,mP,mT, cT
D- Severe mid latitude climates
continental climates, coldest month less than 0 degree C, between 40 and 70 degrees N ->humid continental and subartic, No D climate in southern hemisphere, four seasons
thunderstorms
convectional storms with lightning, warm moist air rising, cumulonimbus clouds; 3 stages: cumulus stage, mature stage, dissipating stage. -individual air mass storms, associated with cyclonic storms. most frequent in the tropics and over land. florida has the most dangerous ones. many storms in the southwest or rockies. lightning is a discharge of electrical energy (100 million volts)
what are the main sources of atmospheric lifting
convective, orographic(mountain caused), frontal/cyclonic(warm air masses run into cool air masses), convergent(whenever air converges and rises)
stratus
layers of sheets of cloud that cover the sky; large mass of air uplifted; stratiform
3 states of water
liquid, freezing, ice
nimbostratus
low rain louds covering the sky in a layer
saturation
situation in which the air contains the maximum amount of water vapor possible for a given temperture. The higher the temperture the more water vapor in the air.
What are the characteristics of an anticyclone, or high pressure system (temperature, dynamics)?
An anticyclone is a region of high pressure. Winds, generally light, circulate around the high pressure centre in a clockwise direction in the Northern Hemisphere and anticlockwise in the Southern Hemisphere. Anticyclones are usually associated with fair weather in the summer and dry, cold, and sometimes foggy weather in the winter. Air at the center of an anticyclone is forced away from the high pressure that occurs there. That air is replaced in the center by a downward draft of air from higher altitudes. As this air moves downward, it is compressed and warmed. This warming reduces the humidity of the descending air, resulting in few clouds and low humidity.
E Polar Climates
ET,EF = no month has an average temp above 10 degrees C
Coriolis effect
deflection of moving fluids and objects as a result of Earths rotation
cumuloninbus
high cloud, both wispy and puffy
cumulus-
mass or pile- puffy rounded clouds; parcels of air have been uplifted; cumuliform
Am
moonsoon climate- rainfall peaks in summer, one or more months see more than 6 cm of rain, record:highest rainfall in one year, heavy seasonal rains
characteristics of a cyclone
- a storm or system of winds that rotates around a center of low atmospheric pressure. -Cyclones are typically indicators of rain, clouds, and other forms of bad weather. -Winds= blow counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere. -Winds in an anticyclone blow just the opposite. - cyclones, air close to the ground is forced inward toward the center of the cyclone, where pressure is lowest. It then begins to rise upward, expanding and cooling in the process. This cooling increases the humidity of the rising air, which results in cloudiness and high humidity in the cyclone.
Define air pressure. What influences air pressure in the open atmosphere?
-Air Pressure - Average force exerted on a unit area by molecular collisions -Factors Influencing Air Pressure: (If all else is equal, in the open atmosphere). : ->As altitude increases, pressure decreases ->As amount of water vapor increases, pressure decreases ->As temperature increases, pressure decreases ->Pressure ->Decreases at the surface where air is rising ->Increases at the surface where air is subsiding
How do the pressure gradient, coriolis effect, and friction interact to determine wind direction and speed in the Northern Hemisphere? The Southern Hemisphere? In the upper part of the troposphere away from the influence of the land surface? (idk the answer to this help)
-Wind blows from high to low pressure as it follows the wind gradient. -The coriolis effect is the deflection of moving fluids and objects as a result of Earths rotation. In the Northern Hemosphere there is defleection to the right, in the Southern Hemosphere, there is deflection to the left. Maximum is at the poles. Zero at the equator. THe coriolis effect is proportional to the speed of the moving fluid. -Friction acts to slow the movement of air. By slowing air movement, friction also reduces the Coriolis force, which is proportional to wind speed. This alters the force balance in favor of the pressure-gradient force with the outcome that there is a movement of air at an angle across the isobars toward the area of lower pressure.
cold front
-a cold air mass invades a mass of warmer air -leads to cumulonibus clouds, thunderstorms are common -steep slope -rapid uplift of air -high intensity perticipation moves fast -triangles moving in direction the cold front moves is the symbol
What is a mid latitude (also called extratropical) cyclone?Where are they found?
-a mid latitude cyclone-migrating low p-ressure system -they are found 35 to 70 degrees north and south extra factors include: may be 1000 miles across, pressure 990-1000 mb, counterlockwise in NH
stationary front
-neither air mass advances -temp changes -low pressure along front -wind shift -line with half circle on one side and triangles on the other
What are the three main factors influencing direction and speed of the wind?
1.Pressure gradients -Wind follows the pressure gradient, that is, wind blows from high pressure to low pressure -Can be mapped with isobars 2.Coriolis effect -Deflection of moving fluids and moving objects as a result of the Earth's rotation -Northern Hemisphere: deflection to the right -Southern Hemisphere: deflection to the left -Maximum at Poles -Zero at Equator -Proportional to speed of the moving fluid 3.Friction polly cries frequently
1. What is a thermal low? 2. A dynamic low? 3. A thermal high? 4. A dynamic high?
1.Warm rising air leads to low pressure, if all else is equal 2.Cold, subsiding air leads to high pressure, if all else is equal 3.Air converging at high altitude, then subsiding to the surface, leads to high pressure, if all else is equal 4.Air converging at the surface, then rising, leads to low pressure, if all else is equal
isobar
A line on a weather map connecting points of equal atmospheric pressure.
Santa Ana wind-How is each generated, and what effects does each have on the weather?
A type of chinook; warm winds flow downslope
Tropical (A) climates
Af, Aw, Am,tropical humid, within 20 degrees of the equator, average monthly tempertures are greater than 18 C
BWh
B climate -subtropical desert climate: hot, dry deserts, associated with high pressure, west coast/ cold currents, high temps and little precipitation all year. deserts include : west coasts in the subtropics, cold ocean currents, cold current deserts are the DRIEST of all deserts
BWk
B climate- midlatitude desert climate- dry, cold winters, rainshadow and interior deserts
Dry B climate
BWh, BWk; annual precipation is less than potencial water loss by evaporation, 30 percent of Earths land area is in it. causes for deserts:subtropcial highs, rainshadow, west coast desers/cold currents
katabatic wind-How is each generated, and what effects does each have on the weather?
Cold winds that flow downslope under the influence of gravity.
cT
Continental tropical - northern mexico, Southwest U.S., hot and dry
Mild mid latitude climate
Cs, Cfa/Cwa, Cfb/Cfc
Subartic Climate
D climate short cool summers, long very cold winters, GREATEST range in temp
Humid Continental climate
D climate., mild summers, cold winters and many cyclonic storms
What happens to the latent heat when water evaporates, condenses, freezes, or thaws?
Latent heat when water evaporates is absorbed. When it condenses or freezes it is released.
Cfb, Cfc
Marine West Coast Climates- cool, mild tempertures, rainy all year, western sides of continents, 40 to 65 degrees N and S
mP
Maritime polar- northern pacific and atlantic oceans, cool moist
mT
Maritime tropical- carribean and tropical pacific oceans, warm and humid
Cs
Mediterranean climate- dry summers, mild wet winters, coldest month above 0 degrees C, west coast of continents, centered on 35 degrees N and S
Intertropical convergence zone
Near the equator, from about 5° north and 5° south, the northeast trade winds and southeast trade winds converge in a low pressure zone known as the Intertropical Convergence Zone. The air rises through convection which causes lots of rainfall.
Polar Easterlies
The polar easterlies are the dry, cold prevailing winds that blow from the high-pressure areas of the polar highs at the north and south poles towards low-pressure areas within the Westerlies at high latitudes. Cold air subsides at the pole creating the high pressure, forcing a southerly (northward in the southern hemisphere) outflow of air towards the equator.)
cyclone
a system of winds rotating inward to an area of low atmospheric pressure, with a counterclockwise (northern hemisphere) or clockwise (southern hemisphere) circulation
rainshadow
dry region on the leeward side of mountain range
Doldrums
exist in a belt circling the globe, near the equator; this belt consistently features low atmospheric pressure, a lack of significant winds and weather that is often cloudy and rainy
Cfa, Cwa
humid subtropical climates- humid hot summers, mild wet winters, eastern sides of continents, centered on 35 degrees N and S
EF
ice cap climate- every month is below freezing, no vegetation, ice and snow, antarctica and greenland, record LOW temp
precipitation
includes rain, hail and snow.
What drives surface ocean currents?
prevailing winds
Westerlies
prevailing winds from the West towards the East in the middle lattitudes between 30 and 60 degrees. The winds are predominantly from the southwest in the Northern Hemisphere and from the northwest in the Southern Hemisphere.
Aw
savannah climate- driest of the 3 A climates, VERY seasonal- summer rain and dry winter, tropical grassland vegatation, hot and seasonally dry
koppen system
system in which climates are established
dew point
temperture at which the air is completely saturated
occluded front
the cold front overtakes the warm front -all air forced up -intense precipitation -mechanisms for lifting air -storm dies out -symbol is triangle and half circle up
tornados
they are cyclones. features: extremly low pressure, extreme pressure gradient, winds 100-300+, updrafts 100+, moves 20-30 mph, warm humid air, strong updrafts, wind speed increases with ALTITUDE. 90 percent occur in the US
Af
tropical wet climate, every month more than 6 cm of rain, HIGHEST annual precipitation
absolute humidity
vapor content in mass per unit volume: grams of vapor/ cubic meter of air
anticyclone
weather system with high atmospheric pressure at its center, around which air slowly circulates in a clockwise (northern hemisphere) or counterclockwise (southern hemisphere) direction. Anticyclones are associated with calm, fine weather.
