GEOL Exam 3
How and why phase change occurs (ice>water>water vapor)
(heat)energy is added (absorbs) to and removed (releases) from the matter
Types of radiation Sun produces (difference between short wave and long wave) and 4 basic laws of radiation
- All objects emit radiation - hotter objects emit more radiation per unit area then do cooler objects (i.e Sun=hot= lots of radiation while Earth=cold=less radiation). -More intense radiation = hotter = shorter wavelength (gamma, x-rays uv). - Less intense radiation = cooler = longer wavelength (visible, infrared etc.).
Basics of fog / 5 ways fog forms with proper names
- a cloud that forms on or at the ground. it is similar to a cloud in that it forms when air becomes saturated with water vapor but is considered an atmospheric hazard. 1.advection fog- when warm moist air moves over a cool surface. 2.radiation fog- as the earth cools to and past the air's dew point at night. 3.upslope fog- when humid air moves up a slope and adiabatic cooling occurs
Basic temperature patterns/trends of the Earth
- temp decreases as we move towards the poles - warmest and coolest temperatures occur over land - a latitude change in temp occurs with seasons - Southern hemisphere is more stable due to less influence from continents -Equatorial region has least variable while pole regions are most variable
How mid latitudes effect / influence wind processes
The zone of the westerlies - complex weather air flow is interrupted by cyclones Cells move west to east in the Northern Hemisphere Paths of the cyclones and anticyclones are associated with the upper-level airflow
Basic temperature profile of the atmosphere (sometimes use diagram w/ questions)
Troposphere- temperature decreases in this layer as altitude increases. Stratosphere- temperature increase in this layer (in response to ozone's presence). Mesosphere- temperature decreases again in this layer with altitude. Thermosphere- temperature increases in this layer from the high speeds of the gases
What a cloud is made of and the basics of naming them
made of millions and billions of these tiny microscope water droplets/ ice crystals. cirrus= high, thin, wispy, white clouds cumulus= globular cloud masses stratus= thick, dark, sheets that cover much of the sky.
Water
matter; ice, water, water vapor
What humidity measures (how it is temperature dependent) / what saturation means / difference between mixing ratio and relative humidity
measures water vapor... saturation= the point when a parcel of air is filled to the capacity with water vapor... mixing ratio= mass of water vapor/mass of dry air relative humidity= the ration of the airs actual water late to its potential water vapor content at a given temperature.
Types of precipitation (6 types)
rain, drizzle, snow, sleet and glaze, hail, rime
How continents effect/influence wind processes
seasonal temperature differences disrupt the global pressure patterns and global wind patterns Influence is most obvious in the Northern Hemisphere Monsoon = seasonal change in wind direction Occur over continents During warm months - warm, moist air from the ocean flows onto land
Seasons & energy differences
seasons are a result of changing orientation of the Sun relative to the earth (4 components).
Wind
the horizontal movement of air. Always moves out of areas of high pressure Always moves into areas of low pressure
Atmosphere structure
troposphere, stratosphere, mesosphere, thermosphere
What the most important gas in the atmosphere is in terms of heat processes
water vapor
Effects of coriolis and friction on wind
Apparent deflection in the wind direction due to Earth's rotation (deflects to the right in the Northern Hemisphere and to the left in the Southern Hemisphere) Friction - Only important near the surface; acts to slow the air's movement.
How fronts/air masses/cyclones-anticyclones all work together
Are generated and maintained by upper-level air flow Typically are found adjacent to one another Cyclone low pressure system with surface convergence Outflow (divergence) aloft sustains the low pressure Anticyclone High pressure system with surface divergence Associated with cyclones convergence aloft sustains the high pressure
What cyclones and anticyclones are -all their details, where they are most influential
CYCLONES: A center of low pressure - (pressure decreases toward the center) Winds associated with a cyclone In the Northern Hemisphere - inward (convergence) and counterclockwise In the Southern Hemisphere - inward (convergence) and clockwise these are associated with rising air and often bring clouds and precipitation. ANTICYCLONES: a center of high pressure (pressure increases towards the center) Winds associated with an anticyclone In the Northern Hemisphere - outward (divergence) and clockwise In the Southern Hemisphere - outward (divergence) and counterclockwise these are associated with subsiding air and usually bring "fair" weather.
Basics of what air masses are important in the US
Continental polar (cP) form over land/ likely to be dry Maritime polar (mP) form over water/ humid air
What separates air masses
Fronts
Location of Hadley, Ferrel and Polar cells- where low and high pressures are located, why desserts are found at 30o latitudes, name of winds in each zoneHad
HADLEY: Looking from Equator North / South Equatorial low pressure zone a.k.a. (The Doldrums) - at equator have rising air and abundant precipitation Rising air flows Northward to Subtropical high pressure zone a.k.a.(The Horse Latitudes) where air subside and is stable and dry. Near 30 degrees latitude, location of great deserts. Air traveling equatorward from the subtropical high produces the trade winds. FERREL: Air traveling poleward from the subtropical high produces the westerly winds which flow up to subpolar low pressure zone warm and cool winds interact Polar front - an area of storms. POLAR CELLS: Polar high pressure zone at poles cold, subsiding air Air spreads equatorward and produces polar easterly winds Polar easterlies collide with the westerlies along the polar front
How direction heat/energy moves and 3 ways it moves
Heat moves in three ways: Radiation, conduction, and convection. Radiation happens when heat moves as energy waves, called infrared waves, directly from its source to something else. This is how the heat from the Sun gets to Earth. In fact, all hot things radiate heat to cooler things.
• Discuss how clouds are classified and illustrate this approach with 2 specific examples.
Height and form are both used in the classification of clouds 3 Forms: 1. cirrus - high, thin, wispy, white clouds (veil - like) 2. cumulus - globular cloud masses (cauliflower -like) 3. stratus - thick, dark, sheets that cover much of the sky 3 Heights 1. high - >20,000 ft = (cirrus +) 2. middle - 6500 - 20,000 ft = (alto +) 3. low - < 6500 ft = (strato +) One additional type of cloud = clouds of vertical development- aka thunderstorm or cumulonimbus clouds- these clouds cross all 3 heights (1 continuous low to high cloud)
Compare/contrast 3 examples of local wind effects (all result from differential heating)
Produced from temperature differences Small scale winds - several types 1. Land and sea breezes - result from differential heating of land/water 2. Mountain and valley breezes - 3. Chinook and Santa Ana winds - result from adiabatic heating as dry cold airmoves down a mountain
How/why Sun's energy changes over a year resulting in seasons (4 reasons)
1. Angle of any point of Earth of Sun changes as Earth revolves around the sun 2. As a result the length of daylight changes 3. The amount of atmosphere the Sun's energy has to pass through changes 4. The intensity of the Sun's rays change (concentrated vs. spread out) -All this results in differing amounts of solar radiation reaching any point on Earth throughout the year
Ways air can rise and fall (4 mentioned) / stable vs unstable air in terms of clouds and precipitation
1. orographic lifting= elevated terrains act as barriers and interfere with air flow causing air to rise and fall as it passes. This can result in rain shadows- all water is rained out on the windward side of the mountain leaving the leeward side arid and dry. 2. frontal wedging= cool air acts as a barrier and warm air moves up and over. 3. convergence= when air masses near earths surface flow together the only possible result is upward lifting. 4. Localized convective lifting= results when air masses near the earth's surface low together and have no where to go but up.
2 components to measuring wind (speed and direction) - how is this done, What a change in wind direction mean
DIRECTION- winds are labeled from where they originate (ex. North wind blows From the north toward the south) Instrument for measuring wind direction is the wind vane Direction indicated by either Compass points (N, NE, etc.) or Scale of 0º to 360º Prevailing wind comes more often from one direction SPEED- often measured with a cup anemometer CHANGES IN WIND DIRECTION- Associated with locations of Cyclones, Anticyclones often bring changes in temperature, moisture conditions
• Describe the 2 different process that lead to fog with 2 specific examples
Fog is a cloud that forms on / at the ground - fog is similar to a cloud in that it forms when air becomes saturated with water vapor but is considered an atmospheric hazard (reduces visibility) -via cooling process (3 ways) 1. advection fog - when warm moist air moves over a cool surface 2. radiation fog - as the Earth cools to and past the air's dew point at night 3. upslope fog - when humid air moves up a slope and adiabatic cooling occurs -via evaporation (2 ways) 1. steam fog - when cool air moves over warm water and water vapor evaporates forming in a thin steamy layer. 2. frontal fog - when frontal wedging occurs, warm raindrops fall into colder under layer and evaporates
2 ways precipitation forms (ice crystal vs collision coalescence)
Ice crystal process- when temperatures are freezing, water vapor condenses onto ice particle to form condensation nuclei. This process continues forming larger and larger crystals until particle is heavy enough to fall from the sky. Collision-coalescence process- in warm clouds large water droplets form from the characteristic of water being hygroscopic (water seeking). Once a microscopic condensation nuclei forms it draws in more and more water forming a larger droplet until it is large enough to fall from the sky.
• Describe what greenhouse effect is and what global warming is (compare/contrast).
In late 1800's - industrialization geared up with the use of fossil fuels -This in turn caused a greater amount of carbon dioxide to be released to the atmosphere - in theory trapping more of the terrestrial radiation. -Thought is that if we continue to use fossil fuel, produce chemicals that deplete the ozone, and cut down trees that remove carbon dioxide from the atmosphere, things will get hotter.
Energy/Radiation
Incoming solar radiation is made of a number of different waves (energies) that all interact with the atmosphere
What are air masses & how are they classified (2 criteria)
Large body of air -1000 miles or more across and up to several kilometers thick Similar - temperature and moisture at any given altitude Move - and affect a large portion of a continent
Air masses
Large body of air -1000 miles or more across and up to several kilometers thick; similar and move
2 most abundant gases (%) - their stability / other components - their stability / basics about ozone and its importance
Nitrogen gas (78%) Oxygen gas (21%)
Definition & result & importance of scatter, albedo, absorption regarding incoming solar radiation to atmosphere
Scatter- amount of scatter depends on the wavelength of the radiation as well as the interfering materials - gas molecules, dust etc. in the atmosphere redirect the incoming radiation. - reddish sunset and sunrise are example of this (same Sun as noon but we can look at it without damaging our eyes - less energy reaches our eyes from the scattering). Albedo:- equals - the reflected radiation -approximately 30% of incoming radiation is reflected back to space - it is lost from the Earth and has no heating effect. - albedo varies from place - place and time - time depending on ice cover, clouds, angle of the Sun, etc. Absorption: -Nitrogen, the most abundant material in the atmosphere is a poor absorber of incoming shortwave radiation (no heat gain) - Oxygen is the 2nd most abundant material in the atmosphere but is a poor absorber of incoming shortwave radiation (no heat gain) - Water and ozone - absorb UV radiation but are not found throughout the atmosphere (minimal heat gain)
• Describe 2 criteria that define air masses and list the 4 types with symbols.
Similar - temperature and moisture at any given altitude Move - and affect a large portion of a continent Polar (P) - high latitudes/cold Tropical (T) - Low latitudes / Warm Continental (c) - Form over land / Likely to be dry Maritime (m) - Continental polar (cP) -form over land/ likely to be dry Maritime polar (mP) -form over water/ humid air Maritime tropical (mT) - From the Gulf of Mexico and the Atlantic Ocean warm, moist, unstable, air brings precipitation to the eastern united states Continental tropical (cT) - Southwest and Mexico hot, dry and is seldom important outside the source region
Basics of greenhouse (how wavelength changes and its importance to heating)
The Greenhouse effect is how Earth's atmosphere heats up. Just illustrated that a lot of the incoming radiation does not make it to the Earth but ~50% of solar radiation does reach the Earth's surface. The Earth - absorbs this shortwave radiation energy and then reradiates but at a slower (longer) wavelength. - Water vapor and carbon dioxide are very good at absorbing this long wave radiation so Sun's energy after it passes through the Earth is finally passed on to the atmosphere and heating of the Earth atmosphere finally takes place.
Characteristics of cold and warm front (compare / contrast)
Warm front Warm air - replaces cooler air (shown on a map by a line with red semicircles) Clouds become lower as the front nears slow rate of advance Light-to-moderate precipitation... Cold air - replaces warm air (shown on a map by a line with Blue triangles) Slope twice as steep as warm fronts (advances faster than a warm front) Associated weather is more violent than a warm front Intensity - of precipitation is greater while duration is shorter Weather behind the front is dominated by Cold air mass Subsiding airClearing conditions. wall of dark clouds heavy precipitation- hail and occasional tornadoes After the passage of a cold front winds become more northerly, skies clear, and temperatures drop
Humidity
a measure of water vapor
Factors influencing wind (most important, pressure difference - how it moves)
always moves out of high pressure areas and always moves into areas of low pressure.
How relative humidity changes (2 ways)
as temperature increases, relative humidity decreases... as temperature decreases relative humidity increases.
Basic idea of air pressure and what happens to it as we move up in the atmosphere
atmospheric pressure describes the weight of the air above - at sea level = 14.7 pounds per square inch - pressure decreases with increasing altitude - ~50% of atmosphere lies below 3.5 miles elevation - ~90% of atmosphere lies below 10 miles elevation - atmosphere thins as we travel away from the Earth's surface
Definition of a calorie and latent heat
calorie- a unit of measure that equals the amount of heat necessary to raise the temperature of 1 gram of water and 1 degree celsius. latent heat- store or hidden heat (not associated with temperature change), causes phase change
Definition of weather
describes the atmospheric conditions of short time periods (variable)
Steps of phase change with proper terminology and calories involved
evaporation= liquid to gas (540 calories) condensation= gas to liquid (540 calories) melting= solid to liquid (80 calories) freezing= liquid to solid (80 calories) sublimation= solid to gas (620 calories) deposition= gas to solid (620 calories)
Clouds
form when water vapor condenses to liquid water from the cooling of the air to and past its dew point. Cooling occurs due to the temperature decrease that exists in the troposphere as elevation increases and due to adiabatic processes (changes in the air pressure)
What geostrophic winds are
generally blow parallel to isobars
Important factors influencing temperature
humidity- aka heat index wind- aka wind chill -The amount of solar radiation (heat) which depends on latitude. Land and water interaction, altitude, geographic cloud cover and albedo.
Basic processes that lead to their development (wet and dry adiabatic rates and how these are involved in cloud formation)(sometimes use in a diagram question)
wet adiabatic rate= saturated air, rising/falling cools/heats at a rate of .5 degrees Celsius per 100 meter change in elevation. Dry adiabatic rate= unsaturated air, rising/falling cool/heats at a rate of 1 degree Celsius per 100 meter change in elevation
