-concentration in atmosphere varies from place to place

-invisible until it becomes liquid (through condensation)

-condensation releases large amount of latent heat

-water vapour is a greenhouse gas

-only 0.038% of atmosphere

-enters mainly from decay of vegetation/volcanic eruptions/fossil fuels

-removal through photosynthesis/ocean absorption

-risen more than 20% since '58

-levels were stable before industrial revolution-

-important greenhouse gas

-97% found in stratosphere -still, less than 0.002% volume

-protects from UV radiation

aerosols

early atmostphere

-hydrogen and helium mostly at first, along with hydrogen compounds (CH4, NH3)

-outgassing occured to great extent..

-over time, rain fell and CO2 dissolved into oceans

-O2 came slowly as sun's rays sply H2O molecules

air density vs air pressure

AD-number of molecules in given space

AP-amount of force exerted over an area of surface (a weight)... always decreases with increasing height

* both decrease rapidly at first (/w altitude), then more slowly.

rate at which temperature decreases with altitude

-up to around 11km... it is the region that contains all the weather with which we are familiar

-kept well stirred with rising and descending currents

-at top, air stops becomming colder with elevation (tropopause)

area in atmosphere where lapse rate equals zero

(T constant with altitude)

-this occurs at the "pauses" - tropopause, stratopause, mesopause

-layer with temperature inversion... b/w tropo and meso

-temp inversion due to ozone... it absorbs UV that warms air

-above stratosphere - air extremely thin and low pressure

-top is coldest part of atmosphere (-90)

-hot layer temp inversion (02 is absorbing solar rays)

-few molecules, so small amount of absorption greatly increase T (500C+)

-aurora displays occur here

-a single air molecule will move 100 km b4 colliding with another... therefore wouldn't feel hot to us

-top is approx 500km

heterosphere

-electrified region within upper atmosphere where lots of ions and free electrons exist... begins at approx 60km

-plays large rold in AM radio communication... (which works better at night)

weather (and components)

-condition of atmosphere at any given time/place

composed of:

1)air temp

2)air pressure

3)humidity

4)clouds

5)precip

6)visibility

7)wind

wind direction

-stated in terms of FROM WHERE IS IT COMING

high pressure = clockwise and outward

low pressure = counterclockwise and inward

-high pressure is associated with clear skies and fair weather

-low pressure = storm!!

pressure almost always between 960(low) and 1060(high)

-boundary that separates warm and cool air

-sharp change in T, humidity andd wind direction across this boundary

temp-measure of the average speed of atoms and molecules

heat-energy in the process of being transferred from one object to another because of temp difference b/w them

-the lowest temperature possible (-273C)

-atoms would theoretically posess no thermal motion

convection

conduction

radiation

-T-scale that begins @ absolute zero (no negatives)

-pure H2O freezes @ 0 and boils @100

C=5/9(F-32)

K=C+273

or "hidden" heat

-heat energy required to change a substance from one state to another

-evaporation in a cooling process (absorbs heat which becomes latent)

-condensation is a warming process (releases latent heat

sensible heat

-transfer of heat from molecule to molecule within a substance

-air is an extremely poor conductor of heat

-transfer of heat by mass movement of a fluid (such as air or water)

-these types of medium move freely and currents exist within

-convection also is a word for vertical exchage of heat (when ground warms air, it rises)

-rising air bubbles

-they expand gradually as they rise and then slowly sink and condense again

-energy transferred through air in waves that do not warm air... i.e. from sun to your face

-these waves are called ELECTROMAGNETIC waves

-they do not need molecules to propagate them

-average wavelength of visible light in 0.5 micrometers

-longer waves carry less energy than shorter ones

1)all things emit radiation (unless T is absolute zero)

-energy comes from rapidly vibrating electrons

2)wavelength of radiation depend on an object's temperature

-higher temp=shorter wl=higher energy

3)objects of high T emit wls at greater rate/intensity than lower T objects

visible region

-part of EMS that we can see (400-700nm wl)

-sun emits max amount of radiation @ visible light (greatest intensity/rate, not greatest size)

-violet=shortest wl of visible light (any shorter would yield UV light)

-red=longest =longer would yield infrared

-earth emits mostly longwave infrared

-sun emits mostly shortwave

-object that is both a perfect absorber (100%) and perfect radiator(100%)

-earth and sun are examples of this

-average T when rate of absorption equale rate of radiation(radiative equilibrium)

-earth's is -18C (255K)

-such as atmosphere

-selectively absorb/emit

-these kinds of gases keep earth's temp around 15C

-atmosphere is not a blackbody

-area where atmosphere does not reabsorb wavelengths from earth but allows them to pass into space

i.e. b/w 8-11 micrometer wavelengths pass through CO2 and water vapour

-air temp over last century has risen by 0.6C

-water vapour = 60% of effect

-CO2 = 26% of effect

-greenhouse effect is not actually like a greenhouse!

-rapid T increase due to positive feedback...

clouds are negative feedback

solar constant

-amound of radiation received from sun at top of atmosphere -

it is 1367W/m²

-when sunlight strikes very small objects such as air molecules and dus particles, the light is deflected in all directions

-reason for sunsets, as only long wavelengths survive the journey through such a thick chunk of atmosphere

-% of radiation returning from a given surface compared to the amound of radiation initially striking it

-i.e. it is the reflectivity of a surface

-snow,clouds=very high albedo

water=apppprox 10%

-tilt = 23.5

-average distance to sun - 150million km (comes closer in january and july)

-seasons regulated by amound of solar energy received at earth's surface

1)intensity of angle

2)length of exposure per day

-earth's axis points always in the same direction

-NH toward  sun in summer and away in winter (duh)

-astronomical first day of summer - june 21

-sun and moon directly overhead

-NH points directly at sun

-occurs during some years when there is an unusually warm period in autumn - occurs in eastern 2/3 of USA

-occurs when large high pressure areas stall near SE coast- clockwise flow moves air from gulf of mexico to states

-march 20- marks arrival of spring (NH)

-days and night are equal all over the world, and north pole sees sun for first time in 6 months

-basically opposite of NH

-earth closer to sun in Jan than in July, but NH have warmer summers

-amount of water makes the difference (acts as a buffer, absorbs heat)

-***this also keeps SH winters warmer!

-in NH, objects facing south will receive more sunlight in a year than thoe facing north

-ski slopes typically face north

-this is important for designing a home!

forced convection

-measured increase in air temperature just above the ground

-occurs mostly at night and when calm

1))windless night (breeze mixes air)

2)long night (longer time of radiational cooling (winter nights are best)

3)clear sky and dry air (ground radiates to exosphere and therefore cools rapidly

-warm hillsides (cold air drains downwards)

-vally bottoms usually not only colder by also more polluted

-cover small plants with tarp, so as to prevent escaping radiation

-orchid heaters warm air and ground around trees by setting up convection currents near ground

-wind machines mix cold air near ground with warm air above

-trees can also be protected by flooding with irrigation

-when a "freeze" occurs (cold wind), fruit can be frozen with mist to protect them

1)latitude

2)land/water distribution

3)ocean currents

4)elevation

-amount of heat needed to raise 1g of something

1C

-difference b/w T at night and T during day

-humid regions have small diurnal temperature ranges

-is the difference of the average T b/w warm and cold months

-largest usually noted on the mainland

HDD-based on the assumption that people will begin to use their furnaces when T drops below 65F

-i.e if it is 64F average during day, then this is 1 heating degree day

-helps to estimate the amount of fuel use

CDD-when T rises above 65F

-index used by farmers

-one of these occurs when T is 1 degree above minimum for given crop

-when wind blows, warm layer of air that surrounds out body is blown away. this layer normally helps us to feel warmer than it really is

-wet skin is a factor in how cold we feel (H2O conducts heat away from body)

liquid in glass- basic

maximum - showest highest /w zone of constriction

-minimum - index marker shows lowest

-electric thermometers - highly accurate

-radiometer - instruments that measure emitted infrared radiation.. can estimate air T in selected altitudes

-thermograph-measures T by using bimetallic thermometer... 2 different pieces of metal in a single strip - brass expands more than iron and therefore bends the strip to read T

H2O

CO2

CH4

N2O

O3

CFCs

30%

clouds=20

aerosols=4

surface=6

warm air comes up from south (pulled up)

-opposite of trough (allows cold air to sink in)

milibar - winds, atmospheric action (shows westerlies, ridges, troughs, jetstreams etc)

1milibar = approx 10m elevation (total =5km)

surface - what is happening on the ground (shows high/low pressure zones, cold and warm fronts storms, etc,)

difference b/w westerlies and jetstreams

westerlies-Westerlies is the prevailing winds in the southern tropics and the easterlies are the prevailing winds in the northern tropics

jetstreams-Jet streams are relatively narrow bands of strong wind in the upper levels of the atmosphere. The winds blows from west to east. Jet streams follow the boundaries between hot and cold air 

**a jetstream is a westerlie**