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Attribution
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Earth's energy budget not perfectly balanced.
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Lifting condensation level
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altitude at which an air mass rises where it is cooled to the dew point temperature, condensation begins, and clouds form
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Cyclone
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low pressure center; clouds
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Rossby waves
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separate cold polar air from warmer tropical air
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Inter tropical convergence zone (ITCZ)
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region near or on equator, high rainfall, persistent cloud cover, low air pressure
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Air masses
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large, variable parcels of air that are distinct from one another. 1600 km across and several km deep, homogeneous physical characteristics of temp., humidity, and stability
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Dry adiabatic rate
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Cooling of 10 degrees C per 1000 meters
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Storm surge
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wind driven water above normal tide level when hurricane pounds into a shoreline
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Radiation fog
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results when ground loses heat through radiation, usually at night
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Wind sheer
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significant change in wind direction or wind speed w/increase in elevation
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Gyres
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large, circular ocean currents centered on subtropical convergence
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Easterly wave
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long but weak migratory, low pressure system, is a tropical disturbance
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Saffir-Simpson hurricane scale
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rank intensity of hurricanes 1-5, 5 most severe
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Mountain breeze
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mountain slopes lose heat rapidly through radiation, chills adjacent air, causing it to slip downslope
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Continental polar (cP)
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north Canadian air, dry, cold, and stable
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Occluded front
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cold front overtakes warm front
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Upslope/Orographic fog
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created by adiabatic cooling when humid air climbs a topographic slope
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Mechanisms of deep water formation
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1.cool surface water 2.make surface ocean saltier a.increase evaporation b.ice formation and brine exclusion
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Buoyancy of air
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tendency of an object to rise in a fluid; warm air more buoyant
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Continental arctic (cA)
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air mass originates far north, dry, cold, and stable
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Hurricane
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centered on strong lows, wind spirals inwards. Latent heat energy converted to wind energy; drop in pressure=storm. Form in warm, subtropical waters. Damage done through heavy rain, high winds, and storm surges
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Trade Winds
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cover most of earth between 25 deg. N and 25 deg. S, major wind system of the tropics, flows toward west from east. (Winds of commerce)
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7 basic surface components, pole to equator
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polar high, polar easterlies, polar front (subpolar low), westerlies, subtropical high, trade winds, and ITCZ
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Atmospheric pressure
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force exerted by gas molecules on some area of Earth's surface or on any other body, even ours.
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Thermal high
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very cold surface conditions associated w/high pressure at surface
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Equatorial counter-current
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reverse flow, west to east, drives el nino and la nina
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Detection
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0.74 degree increase in global mean temp. over last 100 yrs; sea level rising
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Pressure gradient force
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air forced from high pressure to low pressure
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Saturated adiabatic rate
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Cooling of 6 degrees C per 1000 meters above the LCL
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Tropospheric lapse rate
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rate of temp. decreases with increasing elevation; 6.4 degrees C per km
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Midlatitude anticyclones
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extensive, migratory high pressure cell of midlatitude, larger than cyclone and moves west to east w/ westerlies
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Cyclogenesis
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birth of cyclone, common cause is upper troposphere conditions in vicinity of polar front jet stream
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Forcings
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processes causing Earth to emit or retain more energy. Biggest forcing= CO2 in retaining heat; primary suspect is Greenhouse effect, reduces release of longwave radiation
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Advection fog
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develops when warm, moist air moves horizontally over a cold surface. Ex. sea to land
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Millibar
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common unit of measure for atmospheric pressure
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Dynamic high
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strongly descending air associated w/high pressure at the surface
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Sea breezes
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caused by daily differential heating of ocean and land. Day- surface winds move onshore, night- surface winds move offshore.
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Dew
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originates from terrestrial radiation, cools objects at night at Earth's surface. The air is cooled enough to reach saturation, and tiny beads of water collect on cold surfaces of objects
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Coriolis force
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angular velocity higher at equator than at poles; causes deflection of moving objects, caused by Earth's rotation, right in NH and left in SH
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Jet streams
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9-12 km high, displaced poleward, zone of strong winds w/in upper troposphere westerly flow.
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Convectional lifting
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pressure of unstable air decreases as air rises, and so it cools adiabatically to the dew pt. temperature. Condensation begins and a cloud forms
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Gulf Stream
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western arm of North Atlantic gyre
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Midlatitude cyclone
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day to day weather changes and bring precip., 35-70 degrees lat. Vast cell of low pressure air. Starts w/cyclogensis- development of low pressure zone and rotation around it, then open stage-2 well defined fronts, occluded stage- cold front catches warm front, dissolving stage- dissipates
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Maritime tropical (mT)
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moist, warm, stable air
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Rain shadows
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maritime air masses lifted over mountains, releases precip. Dries out air mass after over mountain
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Hadley cells
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low latitude cells, 1 north 1 south of equator; gigantic convection systems
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Convergent lifting
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air converges on low pressure zone, results in uplift b/c of crowding. Results in instability and maybe showers
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Horse latitudes
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center of STH air primarily subsiding, horizontal air movement and divergence begins toward the edges
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Maritime polar (mP)
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starts as cP then moves off land. Cool, moist, and unstable
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Lake effect
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air mass picks up moisture, energy from lake and heat. Releases snow downwind, because air warms and then cools.
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Continental tropical (cT)
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not important in N. America, source region not extensive
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Evaporation fog
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results when water vapor is added to cold air near saturation
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Geostrophic flow
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wind moving parallel to the isobars; idealized wind pattern that results from interaction of pressure gradient force and coriolis
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Frontal lifting
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warmer air forced to rise, may be cooled to dew pt. w/resulting clouds and precip.
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Projection
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highest warming over land, mostly in N hemisphere. Wet regions will get wetter, dry will get drier
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Equatorial (E)
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air affects N. America in association w/hurricanes
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General Circulation Models (GCMs)
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3-d models of atmosphere.
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Cumulonimbus
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Storm clouds
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Orographic lifting
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topographic barriers block path of horizontal air movements, cause large masses of air to move upslope
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Isobar
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lines of equal pressure
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Ekman spiral
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wind drags surface water, surface water drags subsurface water layers, each water layer deflected by Coriolis
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Anticyclone
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high pressure center; clear conditions
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4 challenges of climate change
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detection, attribution, projection, adaptation/mitigation
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Promoting instability in air masses
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surface heating and surface evaporation
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Subtropical high (STH)
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large semipermanent high pressure cell located at 30 degrees lat.
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Types of clouds
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Cirrus, stratus, and cumulus
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Oceans
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circulation driven by density, deeper is colder, saltier, and denser. Net water current is 90 degrees to wind direction.
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Barometer
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measure atmospheric pressure
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Valley breeze
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heated air mass rises, creating low pressure area, and cooler air from valley floor flows upslope from high pressure area to low pressure area
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