First Exam Review Sheet Flashcards

Weather and Climate (LOCK IN B's get new nintendo games)

What are the three primary gasses in our atmosphere today and what concentrations do they exist in? (chapter 1)

• Nitrogen (N2) = about 78%

  • most abundant gas in the atmosphere

  • relatively inactive and does not easily react with other substances

• oxygen (O2) = about 21%

  • essential for respiration in most living organisms

  • supports combustion (burning)

• Argon (Ar) = about .93%

  • noble gas

  • chemically inactive and does not participate much in atmospheric processes

• other gases

  • carbon dioxide (CO2) = about 0.04%

  • water vapor = varies from 0-4% depending on location and weather

(chapter 1) what caused our first atmosphere to form?

• earth formed about 4.6 billion years ago

• the first atmosphere developed from

  • hydrogen and helium gases captured from the solar nebula (cloud of gas and dust that formed the solar system

• this atmosphere did not last because

  • earth’s gravity was too weak to hold these light gases

  • solar wind from the young sun blew so much of it away

resulting in earth’s first atmosphere disappeared

(chapter 1) what led to the build up of oxygen in our atmosphere?

• early earth’s atmosphere contained very little oxygen

• Oxygen began accumulating because o f

  • photosynthesis by cyanobacteria (blue-green algae)

• photosynthesis process

  • organisms used sunlight, water and carbon dioxide

  • Released oxygen as a by product

• over millions of years

  • oxygen is accumulated in the atmosphere

  • this even is called the Great Oxygenation Event

• importance

  • it allowed more complex life forms to evolve

  • led to the formation of the ozone layer

(chapter 1) What are the 4 main layers of our atmosphere as defined by temperature changes? Know how temperature change in each the relative orders of the layers, and at least one phenomena

1) troposphere

• Lowest atmospheric layer

• extends from Earth’s surface to about 8-18 km

• temperature: decreases with height

Phenomena: clouds, rain, snow, and all weather occurs here.

2) Stratosphere

• above the troposphere

• extends to about 50 km

• temperature: increases with height

WHY → ozone absorbs ultraviolet radiation from the Sun.

Phenomena: ozone layer and jet aircraft often fly here

3) Mesosphere

• extends from about 50 - 85 km

• temperature: decreases with height

Phenomena: meteors burn up here

4) Thermosphere

• above the mesopshere

• extends hundreds of kilometers into space

• temperature: increases dramatically with height

Phenomena: auroras (Northern and southern lights), many satellites orbit here

temperature patterns to know:

Troposphere: ↓ Temperature

Stratosphere: ↑ Temperature

Mesosphere: ↓ Temperature

Thermosphere: ↑ Temperature

Think:

Down – Up – Down – Up

(chapter 1) What destroys ozone in our atmosphere?

• natural destruction

  • ultraviolet radiation breaks ozone apart

• human caused destruction

  • Chlorofluorocarbons (CFCs) from: older refrigerators, air conditioners, aerosol sprays

• CFCs release chlorine atmos

• one chlorine atom can destroy thousands of ozone molecules

(chapter 1) What importance does ozone have in our atmosphere and where it is concentrated?

• importance

  • ozone absorbs harmful ultraviolet (UV) radiation from the Sun

  • protects living things from: skin cancer, eye damage and DNA damage

• Location

  • concentrated in the stratosphere and roughly 15-35 km above earths surface

this region is called the ozone layer.

(chapter 1) what is the main difference between weather and climate?

• weather

  • short term atmospheric conditions

  • changes from hour to hour and day to day

• examples:

  • rain today, snow tomorrow

  • temperature this afternoon

• climate

  • long term average weather patterns

  • usually measured over 30 years or more

examples: florida is so warm while Alaska is cold

Easy memory trick:

weather = what you are wearing today

climate = what is in your closet

(chapter 1) What is the environmental lapse rate?

• the rate at which air temperature decreases with increasing altitude

• average environmental lapse rate

  • about 6.5*C per Kilometer

  • or above 3.6* F per 1,000 ft

• meaning as you go higher into the troposphere, temperature usually gets colder

(chapter 1) how does the height of the tropopause differ at varying latitudes? Why does it vary?

• tropopause

  • boundary between the tropopause and stratosphere

• near the equator

  • higher about 16-18 km

• mid latitudes about 20-12 km

• near the poles

  • lower about 8 km

why?:

• the equator receives much more solar energy

• warm air expands and rises

• this causes the troposphere to become deeper

• polar regions are colder

• cold air is denser and compressed

• troposphere is shallower

easy memory trick : warm air expands = higher tropopause

cold air contracts = lower tropopause

(chapter 1) what is a temperature inversion?

• a situation where temperature increases with height instead of decreasing

• normal atmosphere

  • higher altitude = colder

• inversion

  • higher altitude = warmer air

• effects

  • traps pollution near the ground

  • can create poor air quality

  • limits vertical air movement

(chapter 1) what causes atmospheric pressure and what is the relationship between pressure and altitude?

• causes of atmospheric pressure

  • atmospheric pressure is caused by the weight of air above you

  • gravity pulls air molecules toward earth

• relationship with altitude

  • as altitude increases

    • there is less air ABOVE you

    • pressure decreases

Key points →

1) higher altitude = lower pressure

2) lower altitude = higher pressure

(chapter 1) what is the rate at which pressure (or atmospheric mass) changes with height?

• pressure decreases rapidly with altitude

  • about 50% of the atmosphere’s mass is below 5.5km

  • about 90% is below 16 km

• rule of thumb: pressure is approximately cut in half every 5.5 km

Example:

• surface = 1000 mb

• 5.5 km = 500 mb

• 11 km = 250 mb

(chapter 1) what is partial pressure?

• the pressure contributed by an individual in a mixture

• the atmosphere is made of many gasses nitrogen, oxygen, argon and carbon dioxide

  • each gas contributes part of the total pressure

• so if the total atmospheric pressure is 1000 mb oxygen is about 21%

  • the oxygen’s partial pressure if 0.21 × 1000 = 210 mb

(chapter 1) be familiar with the relationship between pressure, density and temperature which can be observed in the ideal gas law.

• the ideal gas law is P=ρRT

where:

P = pressure

p = density

R = gas constant

T = temperature

Relationship 1:

• if temperature stays the same

Density ↑ → Pressure ↑

Density ↓ → Pressure ↓

Relationship 2 :

• if density stays the same

Temperature ↑ → Pressure ↑

Temperature ↓ → Pressure ↓

Relationship 3:

• if pressure stays the same

Temperature ↑ → Density ↓

Temperature ↓ → Density ↑

easier way to remember →

• warm air = less dense

• cold air = more dense

• more molecules packed together → higher pressure

(chapter 1) is the earth the only planet that has an atmosphere in our solar system?

No. Many planets and moons have atmospheres.

• Venus

  • very thick atmosphere

  • mostly carbon dioxide

• mars

  • thin atmosphere

  • mostly carbon dioxide

• Jupiter

  • mostly hydrogen and helium

• saturn

  • mostly hydrogen and helium

what makes earth so special?:

liquid water, large amounts of oxygen, protective ozone layer and temperature habitable for us

(Chapter 2) Know the difference between latitude and longitude- what directions they measure, what directions they run on the globe, what their max values are, what the reference line are)

• latitude

  • measures how far north and south of the equator you are

  • lines run east- west around the earth

  • values go from 0* to 90*

    • so like 40*N means 40 degrees north of the equator

• Longitude

  • measures how far east or west of the Prime Meridian you are

  • lines run north - south from pole to pole

  • values go from 0* to 180*

  • reference line = Prime Meridian (0*)

    • so like 75* W means 75 degrees west of the prime meridian.

(Chapter 2) What is perihelion and aphelion and when do they occur approximately?

• perihelion

  • earth is the closet to the sun

  • occurs around January 3rd

  • distance = 147 million km

• Aphelion

  • earth is farthest from the sun

  • occurs around July 4 th

  • distance = 152 million km

Importance: these does NOT cause the seasons

(chapter 2) know the numerical value of the important lines of latitude such as the equator, tropic of Cancer and Capricorn and the Arctic and Antarctic circles. Why do these lines exist where they do?

• important lines of latitude

  • equator = 0*

  • tropic of cancer = 23.5*S

  • Tropic of Capricorn = 23.5*S

  • Arctic Circle = 66.5*

  • Antarctic circle = 66.5* S

  • North Pole = 90* N

  • South Pole = 90* S

• these lines exist because

  • earth’s axis is tilted 23.5*

  • tropics mark the farthest north and south where the Sun can directly overhead

  • Arctic and antarctic circle mark where 24 hour daylight or darkness can occur.

(chapter 2) what are the equinoxes and solstices and when do they occur?

Equinoxes: day and night are about equal (so 12 hours each)

• Spring (Vernal) Equinox : around March 20-21

• Fall (Autumnal) Equinox : around September 22-23

Solstices:

• summer solstice: around june 20-21

  • longest day in the Northern Hemisphere

• Winter Solstice: around December 21- 22

  • shortest day in the Northern Hemisphere

(Chapter 2) What causes the seasons on earth?

• earth’s axis is tilted 23.5*

• as earth orbits the sun:

  • one hemisphere tilts toward the sun

  • the other tilts away from the sun

• this changes

  • sun angle

  • daylight lenght

  • energy received

NOT cause by the distance from the sun

(Chapter 2) What is solar declination (aka sub solar point), sun angle, and zenith angle? Know the sub solar point on the equinoxes and solstices. be able to approximate it on any day of the year with and without an analemma.

• Solar Declination (subsolar point)

  • latitude where the Sun is directly overhead at noon.

  • Sun Angle = 90*

• Sun Angle

  • height of the Sun above the horizon

• Zenith Angle

  • angle between the sun and directly overhead

  • Zenith Angle = 90* Sun Angle

Key dates Sub Solar points!!! (what are they, seriously lock in)

March Equinox = 0* (Equator)

June Solstice = 23.5* N

September Equinox = 0* (equator)

December Solstice = 23.5*S

• approximate rule:

  • march → moving north from Equator

  • June → reaches 23.5*N

  • September → back to Equator

  • December → reaches 23.5* S

(Chapter 2) Which regions / locations receive 2 days of direct solar radiation, which have 1 day of direct solar radiation, which never have direct solar radiation (Direct meaning sun angle = 90) which can have 24 hours of darkness or daylight.

• 2 days of direct sun each year

  • locations between: 23.5*N and 23.5*S

  • most tropical locations get the sun directly overhead twice a year

• One day of direct sun each year exactly at:

  • tropic of cancer (23.5*N)

  • Tropic of Capricorn (23.5*S)

• Never get direct sun. Areas poleward of :

  • 23.5*S

  • 23.5* N

• Can have 24 hour daylight or darkness areas inside:

  • Arctic Circle (66.5*N)

  • Antarctic Circle (66.5*S)

(Chapter 2) How does the sun angle, daylight hours and solar beam spreading change the latitude and how does this affect temperature variation?

• near the equator

  • high sun angle

  • little seasonal change

  • about 12 hours of daylight year around

  • warm temperatures

• toward the poles

  • lower the sun angle

  • more solar beam spreading

  • greater daylight variation

  • larger seasonal temperature changes

• Solar beam spreading

  • high sun angle → energy concentrated

  • low sun angle → energy spread over larger area

  • spread out energy = cooler temperature

(Chapter 2) Be able to look at a diagram of the Sun and Earth in orbit and determine what season or approximate time of year is being shown.

LOCK IN you must identify the season from an Earth-Sun diagram:

• Northern Hemisphere tilted toward sun

  • Summer

  • Around June 21st

• Northern Hemisphere tilted away from the Sun

  • Winter

  • Around December 21

• Neither hemisphere tilted toward sun

  • Equinox

  • around March 21st or September 23rd

So think →

Sub Solar point at: 23.5*N June solstice, 0* Equinox and 23.5*S December Solstice

(chapter 2) Be able to look at a graph of temperature vs. time or daylight hours vs time (time being the span of a year) and predict the approximate latitude.

Temperature Graph:

• Equator

  • warm all year

  • very small temperature range

• Mid-latitude (30-60*)

  • warmer summers

  • cold winters

  • moderate seasonal changes

• High latitude (60*+)

  • very cold winters

  • cool summers

  • large temperature range

Daylight Hour Graph:

• Equator

  • about 12 hour all year

  • nearly flat line

• mid latitudes

  • noticeable seasonal changes

  • longer summer days and shorter winter days

• Arctic/Antarctic circles

  • extreme variation

  • so it can reach either 24 hours daylight or 24 hours darkness

Memory Trick:

• bigger daylight and temperature swings = higher latitude

• smaller daylight and temperature swings = lower latitude.

(chapter 2) What is the difference between temperature and heat?

• temperature = how hot or cold something is

• heat = energy that moves from a warmer object to be cooler object

• temperature measures the average motion of molecules

• heat is the transfer of thermal energy

So think →

A cup of coffee has a high temperature the heat from the coffee can warm your hands.

(chapter 2) what is sensible and latent heat?

Sensible Heat

• this is heat that can change temperature

• you can measure the temperature with a thermometer

So like heating water from 20* C to 30* C

Latent:

• heat used to change the state of matter (solid, liquid, gas)

• temperature does not change during the phase change

So like water boiling into steam or ice melting into liquid

(chapter 2) What are the 3 types of heat transfer?

THINK CCR!

1) Conduction

• Heat transfer by direct contact

• so like a metal spoon gets hot in a pot of soup

2) Convection

• heat transfer by movement of liquids or gases

• so like warm air rises and cool air sinks

3) Radiation

• heat transfer by electromagnetic waves

• does not require contact or a medium

  • so like feeling warmth from the Sun

(chapter 2) Be familiar with the electromagnetic spectrum (i.e what radiation is short wave and what is long wave and why types of energy and Earth and Sun emit)

Shortwave radiation = energy from the sun

• ultraviolet (UV)

• visible light

• near infrared

Longwave Radiation = energy from the Earth

• mostly infrared radiation

• the sun emits shortwave radiation

• the earth absorbs solar energy and emits longwave radiation

Memory Trick:

sun = short wave

Earth = long wave

(chapter 2) what is Stefan-Boltzmann Law and Wien’s Law?

Stefan-Boltzman Law:

• hotter an object is the more energy it emits a small increase in emitted energy.

  • think hot objects give off much more energy than cool objects

Wien’s Law:

• the hotter an object is the shorter the wavelength of radiation it emits most strongly.

  • so think hotter object emit more shortwave energy. Cooler objects emit more wavelength energy.

FOR EXAMPLEEE→

Sun (very hot) → mostly shortwave radiation

Earth (cooler) → mostly longwave radiation

(Chapter 2) what are 3 ways in which incoming solar radiation can interact with our atmosphere before reaching the surface?

• reflection

  • radiation bounces back to space

  • so like clouds reflecting sunlight

• absorption

  • atmosphere absorbs the energy

  • so like ozone absorbing UV radiation

• Scattering

  • radiation is redirected in many directions

  • so like molecules scattering sunlight

(chapter 2) how much of the radiation coming into the earth system is reflected or absorbed by the atmosphere and ow much reaches the surface?

For every 100 units of incoming solar radiation:

• about 30% is reflected back to space

• about 19% is absorbed by the atmosphere and clouds

• about 51% reaches and is absorbed by Earth’s surface

EASIER WAY TO REMEMBER →

• 30% reflected

• 19% absorbed

• 51% reaches surface

(chapter 2) what does albedo of an object describe? Be able to predict and approximate or relative albedo of a surface based on its color or roughness.

Albedo = the percentage of sunlight a surface reflects

High Albedo:

• reflects lots of sunlight

• usually light colored

Think → Fresh snow, ice, white surfaces

Low Albedo:

• absorbs a lot of sunlight

• usually dark colored

Think → asphalt, forests and dark soil

Roughness:

• rough surfaces usually have a lower albedo

• smooth shiny surfaces often have a higher albedo.

think→

white = high albedo

black = low albedo

(chapter 2) why is the sky blue and why are sunsets (and sometimes sunrises) red-orange?

The sky is blue because:

• sunlight contains all colors

• blue light has shorter wavelength

• blue light is scattered more by air molecules

• we see the scattered blue light in all directions

The Sunsets are red-orange is:

• at sunset sunlight travels through more atmosphere

• most blue light gets scattered away

• red and orange light make it through your eyes

Memory trick →

• blue scatters easily

• red travels farther

(chapter 2) what is the greenhouse effect and what are some main greenhouse gases?

greenhouse effect:

• earth absorbs solar radiation

• earth emits long wave (infrared) radiation

• greenhouse gases absorb some of this outgoing heat

• they then re-radiate heat back toward the surface

• this keeps earth warmer than it would otherwise be.

Main greenhouse gases are:

• water vapor (H20)

• Carbon Dioxide (CO2)

• Methane(CH4)

• Nitrous Oxide (N2O)

• Ozone (O3)

Greenhouse effect is the warming of Earth caused by gases that trap some of the Earth’s outgoing heat.

(chapter 2) be able to define the term seasonality and know how the earth’s tilt affects.

seasonality = regular changes in weather and climate throughout the year.

How does the earth’s tilt affect seasons:

• earth is tilted about 23.5*

• as earth orbits the sun, different parts of Earth receive different amounts of Sunlight

Summer:

• hemisphere tilted toward the sun. More direct sunlight

• longer days and warmer temperatures

Winter:

• hemisphere tilted away from the sun. Less direct sunlight

• shorter days and cooler temperatures.

REMEMBER Sessions are NOT caused by Earth being closer to the sun. Seasons are caused by Earth’s tilt.

• Seasonality is the yearly pattern of weather changes caused by Earth’s 23.5* tilt as it revolves around the sun.

(Chapter 3) what are isotherms (or in general isolines) What does a gradient refer to?

Isotherms

• lines on a map connecting places with the same temperature

• they help show temperature patterns

Isolines

• any line connecting points with the same value

• isotherms= same temperature

• isobars = same pressure

Gradient

• rate of change over a distance

• large gradient means values change quickl y

• a small gradient means values change slowly

(chapter 3) what does zonal and meridional refer to?

Zonal:

• west to east direction

• parallel to the lines of latitude

Meridional

• north to south direction

• parallel to lines of longitude

(chapter 3) how does latitude, proximity to water, geographic position with respect to prevailing winds and mountains, albedo of the surface, ocean currents and altitude affect a location’s temperature and/or precipitation throughout the year?

latitude

• lower altitude (near equator) =warmer

• higher altitude (near poles) = colder

Proximity to water

• water heats and cools slowly

• coastal areas have milder temperatures

• inland areas have bigger temperature swings

prevailing winds:

• winds from oceans usually bring moisture

• winds from land are usually drier

Mountains:

• air rises over mountains and cools

• windward side = wetter

• leeward side = direr (rain shadow)

Albedo

• high albedo reflects sunlight → cooler

• low albedo absorbs sunlight → warmer

Ocean currents:

• warm currents warm nearby coasts

• cold currents cool nearby coasts

Altitude

• higher elevation = lower temperature

• temperature decreases about 6.5*C per km

(Chapter 3) Why does the southern hemisphere vary less in temperature than the northern hemisphere?

• southern hemisphere has more ocean

• water heats and cools slowly

• oceans moderate temperature changes

Result:

• smaller annual temperature range

• less extreme summers and winters

(chapter 3) What is specific heat and how does the specific heat of land and ocean vary?

Specific heat: amount of energy needed to rise a substance’s temperature

Water:

• high specific heat

• heats slowly

• cools slowly

Land :

• low specific heat

• heats quickly

• cools slowly

Remember: water changes temperature slowly. While and changes temperature quickly.

(chapter 3) how does temperature change throughout the span of a day? When is the temperature hottest and when is it coldest? Make sure you know the approximate times and how to describe these times using Earth’s energy budget

Coldest time

• usually just after sunrise

• earth has been losing heat all night

hottest time

• usually 2-4 pm

• surface continues warming afternoon

So why not hottest at noon?

• at noon, incoming solar energy is greatest

• but the surface is still gaining more energy than it loses

• warming continues for several hours

(chapter 3) what is occurring when earth’s energy budget (net radiation balance) is positive? What is occurring when it is negative?

Positive energy budget

• incoming energy > outgoing energy

• surface warms

negative energy budget

• outgoing energy > incoming energy

• surface cools

Easy memory:

positive = warming

negative = cooling

(chapter 3) what is the urban heat island effect and why does it exist?

Urban heat Island: cities are warmer than nearby rural areas

why? :

• concrete and asphalt absorb heat

• less vegetation

• building trap heat

• card and buildings release that heat

Thus cities stay warmer especially at night.

(chapter 3) What are the heat and win chill indices and what weather factors do they depend on the most?

heat index: how hot it feel to people

• depends on → temperature and humidity

Wind Child Index: How cold it feels to people

• depends mainly on → temperature and wind speed

Remember :

• heat index = temperature + humidity

• wind chill = temperature + wind

(chapter 3) How does a solar radiation curve differ between a northern and southern hemisphere location over the span of a year?

northern hemisphere

• highest solar radiation in June to July

• lowest in December to January

Southern Hemisphere

• highest solar radiation in December to January

• lowest in June to July

Key Idea → seasons are opposite in 2 hemispheres

(chapter 3) How does a solar radiation curve differ between a tropical and polar climate over the span of a year?

tropical locations:

• high solar radiation all year

• small seasonal changes

Polar locations:

• huge seasonal changes

• very high in summer

• very low or none in winter

Key Idea →

• tropics = stable

• poles = extreme variation

(Chapter 3) How does a solar radiation curve different between a cloudy and sunny day?

Sunny day

• higher solar radiation curve

• more sunlight reaches surface

cloudy day

• lower solar radiation curve

• clouds reflect and absorb sunlight

Key idea →

• sunny = more solar energy

• cloudy = less solar energy

(chapter 4) be familiar with all the phases changes that substance can undergo and does energy need to be absorbed or is it related in the process.

Energy Absorbed (cooling the surroundings)

• melting: Solid → liquid

  • ice → water

• Evaporation: Liquid → Gas

  • Water → Water vapor

• Sublimation: Solid → Gas

  • Ice → water vapor

Energy released (warming the surroundings)

• freezing liquid : liquid → solid

  • water → ice

• Condensation: Gas → Liquid

  • water vapor → water

• Deposition: Gas → Solid

  • Water vapor → frost

Easy Memory Trick

• going toward gas = absorb energy

• going toward solid = energy released

(chapter 4) what are relative and absolute humidity? Why is relative humidity used more commonly?

Absolute humidity: actual amount of water vapor in the air

Relative humidity (RH) : percentage of water vapor in the air compared to the maximum it can hold

Why use relative humidity?

• it tells how close the air is to the saturation

• more useful for forecasting clouds, fog and precipitation

(Chapter 4) what are the 2 ways in which the relative humidity of the air can be changed?

Change the temperature:

• cool the air → RH increases

• Warm the air → RH decreases

Change the amount of water vapor:

• add water vapor → RH increases

• remove water vapor → RH decreases

(Chapter 4) What is the mixing ratio and saturation mixing ratio of an air sample?

Mixing Ratio - Actual amount of water vapor in the air

Saturation Mixing Ratio - maximum amount of water vapor the air can hold at a given temperature

Easy memory trick:

• mixing ratio = what you have

• saturation mixing ratio = maximum possible

(Chapter 4) how does relative humidity tend to change during the day as the temperature changes?

Morning:

• cooler temperatures

• higher relative humidity

Afternoon:

• warmer temperatures

• lower relative humidity

Night:

• cooling temperatures

• relative humidity increases again

(chapter 4) How does temperature affect the air’s ability to hold water vapor?

• warm air can hold more water vapor

• cold air can hold less water vapor

Easy Memory

• warm air = bigger sponge

• cold air = smaller sponge

(Chapter 4) how can humidity be measured using a sling psychrometer?

contains:

• dry bulb thermometer

• wet bulb thermometer

process:

• spin the instrument

• water evaporates from the wet bub

• evaporation cools the wet bulb

Interpretation:

• large temperature difference = low humidity

• small temperature difference = high humidity

(chapter 4) what is the dew point and how can you find the dew point using a mixing ratio vs temp curve?

Dew Point:

• temperature at which air becomes saturated

  • simple meaning: the temperature air must cool to for condensation to begin

Using mixing ratio vs. temperature graph:

• find the air’s mixing ratio

• follow the value until it intersects the temperature curve

• the temperature at the intersection in the dew point.

(chapter 4) What is the air parcel and how does an air parcel change in temperature and dew point as it rises or sinks?

Air Parcel = a small bubble of air moves through the atmosphere

Rising Parcel = expands and cools

Sinking Parcel = compresses and warms

Dew point changes:

• rising : dew point decreases slowly

• sinking: dew point increases slowly

(chapter 4) why is the wet adiabatic lapse rate less than the dry adiabatic lapse rate?

• dry adiabatic rate: about 10*C per km

• Wet adiabatic rate: about 6*C per KM

Why? :

• condensation releases latent heat

• this released heat slows the cooling rate

Easy Memory: wet air cools slower because condensation gives off heat.

(Chapter 4) what is the lifting condensation level? How does the difference in temperature and dew point at the surface affect the height of the LCL?

LCL:

• height where a rising parcel becomes saturated

• cloud formation begins here

Surface temperature and dew point difference:

• small difference

  • air becomes saturated quickly

  • low LCL

• Large Difference

  • air must rise farther

  • high LCL

Easy Memory

• temperature close to dew point= low clouds

• temperature far from dew point = high clouds

(chapter 4) what are the 5 processes that can lift air?

1) Orographic lifting: air forced up mountains

2)Frontal Wedging: Warm air lifted over cold air

3) Convergence: air flows together and rises

4) Localized convective heating: warm surface heats air causing it to rise

5) Turbulent uplift: obstacles or rough surface force air upward.

(Chapter 4) be able to describe and calculate how an air parcel’s temperature and dew point change as it is forced to rise and moves over a mountain given a set of initial conditions.

Before reaching LCL:

• temperature decreases by 10* C/km

• dew point decreases by 2* C/km

At LCL:

• condensation begins

• clouds form

Above LCL:

• temperature decreases by about 6*C/km

• dew point and temperature stay close together

Descending side:

• temperature increases by 10*C/km

• dew point increases by 2*C/km

(chapter 4) how is the windward side of a mountain different than the leeward side?

Windward side:

• faces the wind

• air rises

• cooler

• more clouds

• more precipitation

Leeward Side:

• opposite side

• air sinks

• warmer

• drier

• often a rain shadow

Easy Memory →

• Windward = wet

• leeward = dry

(Chapter 4) What do we mean when we say air is stable or unstable?

Stable air:

• resist rising

• if lifted tends to sink back down

Unstable air :

• Continues rising on its own

• encourages cloud growth and storms

(Chapter 4) Be able to predict whether the atmosphere is in a state of absolute stability, absolute instability or conditional instability based on a graphshowing how the enviornment changes in temperature and how an air parcel changes in temperature.

Absolute stability:

• parcel is colder than environment

• parcel sinks

Absolute instability:

• parcel is warmer than enviornment

• parcel keeps rising

Conditional Instability:

• unsaturated parcel is stable

• saturated parcel becomes unstable

Easy Memory:

• colder parcel = stable

• warmer parcel = unstable

(chapter 4) what can cause a body of air to become more stable or more unstable?

more stable:

• cooling the surface

• warming the atmosphere

More unstable:

• heating the surface

• cooling the atmosphere aloft

Easy Memory:

• warm ground = instability

• cool ground = stability

Is it common to find water in its liquid state on planets other than Earth?

NO. The earth is unique because liquid water is abundant at the surface.

Other planets water may exist as ice, water vapor or underground oceans (possibly).

• Liquid water is not common on the surfaces of other planets in our Solar System. Earth is the only planet known to have abundant water at its surface.