weather and climate

Geography
weather
-current state of the atmosphere
always changes
climate
-a collective state of the Earth’s atmosphere over a long period of time (greater than 30 years)
-example tropical, subtropical
meteorology
– study of the Earth’s atmosphere
– forecasting (educated guess) is an offset of meteorology
atmosphere
-dealing with the gases that surround the Earth and other planets
-mostly nitrogen and oxygen gases
weather affects our daily lives in…
1. Airfare – travel
2. Produce – farming – food
3. Pricing on items
4. Our personal and daily lives
340 BC
-study of meteorology begins.
-Aristotle is known as ” father meteorology”
1593
-thermometers developed by galieo
-measures hot and cold
1640
-barometer is developed by Torcllini
-measures atmospheric pressure
1664
-hygrometeris developed by Foley and da Vinci
-measures humidity
1843
-telegraph was developed by Alexander Bain
-transmit signals by Morse code
1846
4 cup anemometer
measures wind speed
1891
-civilian US weather Bureau
-it was against the law to use the word tornado in the 1950s because it would scare people
1920
– air mass theory developed by Norwegians
-“fronts” became part of whether
1936
-tupelo Mississippi tornado
-went from Mississippi to Kansas NE
-death toll for whites not blacks
-fourth deadliest tornado in history
-this change the way that America looked at weather
1940
-weather bureau to commerce
-move from governments Department of Agriculture in 1890 to governments Department of Commerce
1940s
-upper air balloon
-rawinsound developed due to World War II
-this measures upper-level winds up
1950s
computers were developed and saved weather data-very large
1957
-weather radar was developed.
-They were monochrome (B&W) and have advanced greatly
-they seem rain
1957
-weather radar was developed.
-They were monochrome (B&W) and have advanced greatly
-they seem rain
1960
weather satellite
-predictors for hurricanes
-1900 Galveston hurricane was before any of this was invented
1970
-weather bureau to NWS
-weather bunnies became popular
-Popularized weather through the weather channels on TV
1974
-worst tornado breakout ever!!!
-weather bunnies were out..and in meteorologist stepped in due to the impact of THIS storm
1980s
-Doppler weather radars
-used colors based on reflectivity
-allowed us to see the speed and circulation of wind
1980s
– wind profilers
– taking the Doppler radars in pointing them upwards
-predicts current wind
-supplement upper air balloons (rawisondes)
1990s
weather observation- ASOS
-report hourly observations of weather use by meteorologist in airports
1990s
NWS modernization: centralized many offices into one per area
the eight elements of weather (what a meteorologist forecasts)
v-HPD CAPS!! 1.)visibility 2.)humidity-hygrometer 3.)precipitation-what’s falling?;4.)wind direction-compass;;5.)clouds-formation;;6.)air temperature-thermometer;;w 7.) atmospheric pressure-barometer-(the only invisible element 8.)wind speed-anemometer;
temperature
-measures hot and cold
humidity
amount of moisture in the air
clouds
10 kinds (2 precipitate)-they are key elements in forecasting. Biggest indicators for weather.. Developed by Aristotle
precipitation
falling stuff. Example rain, sleet, snow etc.
wind direction
stated FROM where the winds blow
windspeed
how quickly the air molecules are moving
atmospheric pressure
you can’t see it. Measured by a barometer. Animals can predict the weather
visibility
how far you can see
8 ways we OBSERVE the weather
1. Satellites in space
2. Radar( speed and circulation of wind)
3. Profilers (radars up)upper air
4. Rawinsondes (upper air)
5.surface weather observation
6. Lightning detection network’s
7. buoys
8. Human observation network
isolines/isopleths (6)
lines of equal or constant values of beginner and property( with respect to place and time)
isobars
lines of equal atmospheric pressure
Isotherm
lines of equal air temperature
Isoyet
lines of equal rainfall amounts
isallobar
lines of equal pressure change
Isodrosotherm
lines of equal dewpoint temperature
Isotach
lines of equal windspeed
two types of weather maps
-surface map (0-30 ft)
1)mono-ugly. 2)TV sexy
-upper air map(30ft-tropopause)
surface map
on a surface not you will see
1.) cold fronts
2.) warm fronts
3.) station fronts
4.) pressures ( hi and low) indicated by isobars
**** surface maps have two types… Mono and TV
upper air map
taken twice-daily
NO FRONTS
looks at the wind direction
wind is generally West to East
low-pressure direction
counterclockwise is
high-pressure direction
clockwise
seven causes of weather
1. Suns heat varies over the earth and with seasons
2. Difference in air temperatures over the earth causes the wind
3. Rotation of the earth destroys simple wind patterns (W to E) twisting the wind producing spirals of high and low pressures
4.) since less moisture can coexist in colder air… precipitation is generally caused by cooling the air. cold air cannot contain moisture hence it falls
5.)pressure in the atmosphere ALWAYS decreases with hight
6.)decreasing air pressure> Temp drops(hairspray)increasing air pressure> Temp rises (football pump)
7. Clouds/precipitation are caused by rising air (Low’s)…. Clear skies are caused by sinking air (highs)
the Earth Spheres (4)
hydrosphere-oceans, lakes
lithosphere-crust, land
biosphere-the living part of the planet
atmosphere-mixture of the different gases ( the Composition of the atmosphere is NOT constant. Changes placed a place in time to time
composition of the atmosphere
permanent gases ( 98%)
-nitrogen 78.08%
-oxygen 20.95%
-Argon .93%
-neon .001%
variable gases a.k.a. greenhouse gases(2%)
-water vapor (0-4%) most variable
-carbon dioxide
-nitrous oxide
-ozone
-methane
*these greenhouse gases let sunlight in in traps heat.
continentality
in respects to a location within a continent. Denver has more continentality than Houston.
good ozone
in the stratosphere a.k.a. “filter of the rays”
bad ozone
in the troposphere… Pollution
atmospheric origins
particles and solar winds formed the earth and then it cooled.outgassing occurred including water vapor. Clouds formed rain fell. At first rain “boiled away” after completely cooling the Earth the oceans eventually filled with water.and hydraulic cycle began
formation of oxygen
the first atmosphere contain little amounts of oxygen, how did oxygen as we know it today form?UV radiation through chemical reactions produced some oxygen. Largely most came through photosynthesis
layers of composition
Homosphere-surface to 55 miles up –well mixed region many Atoms
heterosphere-did a small number of atoms molecules higher up
layers by electrical properties
ionosphere-40/50-not a layer, but no electrical region. Molecules (N) and Atoms(O)are readily ionized with energy from sun’s radiation contains the layers (low)D, (mid)E,(high)F
some things to know
the Earth intercepts lesson to billions of all the suns energy!
However solar energy represents 99.9% of the energy that heats the Earth’s surface
if the sudden stop shining and winced I the Earth will cool and die
movement of the earth
Earth rotation-Earth spins on its axis once every 24 hours and is responsible for day in night
-orbital rotation responsible for the earths orbit around the sun every 365 1/2 days.responsible for the seasons
altitude of the sun
More of an angle determines the number of “atmospheres” that the suns rays must traverse.
90° overhead – ( 1 atmosphere)-most direct rays
30°above horizon-(2 atmospheres)
5 to 10° above horizon- ( 11 atmospheres)
the Earth’s seasons
March 21 – vernal equinox
June 21-summer solstice
September 21-autumale equinox
December 21-winter solstice
tropic latitudes
tropic of cancer is located at 23.5° NORTH
tropic of Capricorn is located at 23.5° SOUTH
heat transfer
100% from sun
51% absorbed by Earth
19% absorbed by atmosphere and clouds
20% scattered by clouds
4% reflected by the surface of the earth
* heat in the atmosphere is largely result of the heat on earth surface
four ways to transfer energy
conduction, convection, advection, radiation
1. Conduction-not all materials are conducted. Transfer energy (hot>cold) through material.not very important for meteorology
2.convection-very important for meteorology-it’s the vertical transfer of heat through particles resulting in thunderstorms
3. Advection-the horizontal transfer of energy
4. Radiation- transfer of heat from the sun (short wave-solar, longwave-terrestrial)
scattering
dust and other particles redirects radiation which results in light. Small gas molecules scatter radiation
specific types of scattering (two)
Rayleigh scattering-short waves solar-scatters gases which creates a blue sky
albedo
total fraction of total radiation that is reflected by a given surface ( black, white, etc.)
albedo varies…
Place to place in time to time. Due to cloud cover in particular matter. Due to angle of sunrays. Nature Earth’s surface
average planetary albedo percentage ( 30%)
freshly fallen snow – 80 to 85%
thick clouds – 70 to 80%
old snow – 50 to 60%
thin clouds- 25 to 50%
Sand surfaces- 20 to 30%
green areas – 20 to 25%
dry earth – 15 to 25%
wet earth – 10%
forested areas – 5 to 10%
water overhead – 3 to 5%
* Sun needs to get to the earth surface to heat it
object radiation
*if an object radiates more energy than it absorbs it will become colder
*if an object absorbs more energy than a radiates it will turn warmer
blackbody object
perfect absorber (all of the radiation it receives it absorbs) or a perfect emitter (emits Max radiation possible at a given temperature)
* the not have to be black
“the Earth is a blackbody not the Earth’s atmosphere”
energy
the property have a system that enables it to do work.
ex, kinetic electrical etc.
heat
form of energy that traversed between objects by virtue of temperature differences
heat capacity
ratio heat absorbed or released by a system compared to the corresponding temperatures rise and fall
*the more he it takes to warm the higher the capacity (ocean compared to a pond)
latent heat
“hidden” heat or moisture
-heat energy required for change of state
*evaporation and condensation
evaporation
the evaporation of water is a cooling process.
-heat is hidden away in water vapor
-Evaporation= absorbed latent heat
condensation
the condensation of water is a warming process
-sensible heat is released within rising air particles this causes the particles to be warmer
-latent heat is released
Latitutional heat balance
worldwide average short wave (solar) radiation is balanced by average longwave (terrestrial) radiation this is not true of each latitude north and south.
-At 36° latitude or below or short wave radiation is received and lost
-36° latitude above the opposite is true
the Earth’s atmosphere and to a lesser extent the oceans help transfer colder air to the polls
*** 30-50° is the “war zone” Battle of the atmospheres
temperature measurement
the expansion and contraction of a liquidated on an index scale
-maximum thermometer (Mercury)
-minimum thermometer (alcohol)
-Mercury is now outlawed in federal facilities
ways to measure temperature
Hygrothermometer-looks like a mushroom catches air
radio meters- satellite application
bimetallic thermometer-makes a thermographic chart
rules for thermometer
door to the north no direct sunlight well ventilated shielded from any radiating surfaces 5 feet above ground level in a grassy vegetated area. The more inconvenient the better
temperature scales
Fahrenheit (only in US) and Celsius
Fahrenheit
developed in 1714 by Daniel Fahrenheit
_based on Mercury and the glass barometer based on the zero point
32° – freezing point
98.6°-human temperature
212° boiling point
Celsius
used worldwide developed by anders
using decimal scale where freezing is zero
0°-freezing
37°-human
100°-boiling
*kelvin and Celsius are the same
** degree of Celsius is larger than a degree of Fahrenheit by factor of 1.8
formula for Fahrenheit to Celsius
C = F -32 divided by 1.8
formula for celcius to farenheight
f= 32+(1.8 x C)
controllers for temperature
solar radiation is the primary control
* place to place changes are due to differential heating of land and water, ocean currents, elevated latitude and geographic position
infiltrate
soak to the ground
transpiration
when plants release paper
temperature data uses
temperature data is gathered at thousands of stations worldwide on an hourly basis
uses for temperature data
hourly temperatures, max and min daily, record of high low, heating and cooling growing degree days, daily average temperature, monthly average temp
*these records are sometimes used for CSI data
heating/cooling degree days
HDD/CDD’s were developed by heating engineers
* these are considered units of measurement
-HDD/CDD’s are practical method of evaluating energy, energy demand and consumption
-these degree days are based on the assumption that heating/cooling is not required when it’s 65°F
-formula
examples of degree days
high 90 low 70
high 50 low 40
average the high low temperature…. Find the difference in degrees to 65
avg 80-65= 15 DD cooling
avg 45>65= 20 DD Heatin
HDD/CDD seasons
CDD season-January> December (encompasses entire summer season)
HDD season-July> June 30 ( encompasses entire winter season)
bio meteorological applications
heat stress index
developed by RG steadham ’83
two factors temperature and humidity

-windchill index
developed by polar scientist in the 1940s
two factors air temp and wind speed
* also clothes humidity and solar radiation

water vapor
most important element in the atmosphere
varies from 4% near the equator and 0% at the poles
humidity
the amount of water vapor in the air
relative humidity
ratio of the airs actual water vapor content compared with the amount of water vapor required for saturation at a given temperature.
express as a percentage
total saturation-100%
tells us how close we are to saturation
influences on relative humidity
-adding/subtracting moisture to the air
-changing a given temperature
-daily temp changes
-air moves horizontally
-air moves vertically
dewpoint temperature
the temperature to which a parcel of air would need to be cold to in order for a given parcel of air to become saturated
-it is always less than the air temperature. If same era saturated
how we measure humidity
slinger wet/dry
hair hygrometers
electric hydrogmeters
infared hydrogmeter-sattelitees
atmospheric stability
state of equilibrium of the atmosphere
-stable equilibrium
-unstable equilibrium
in order to determine atmospheric stability……
We look at the temperature of a parcel of air as it rises and sinks in the atmosphere compared to the temperature of the surrounding environmental air…. Micro-analyzing
— if air parcelis warmer than its surrounding parcels of air…. Then it is considered unstable
rises> Cools….. Sinks> Warms
*** the rate at which air cools/warms the pens upon the air moisture content and whether it is saturated or unsaturated
adiabatic and diabatic processes
adiabatic- when parcel of air cools(expands)or warms (compresses) with NO change in atmosphere
diabatic…including changes in the atmosphere
as parcels rise or sink in the atmosphere we assume a Adiabatic process is occurring
unsaturated air (DRY Adiabatic)
-air cools/heats at 5.5/1000ft
saturated air(WET adiabatic)
-air cools/heats 3.3/1000ft
environmental lapse rates ELR
by looking at the environment temperature profile via thermodynamic diagrams( data provided by radiosonde and profilers)we can determine stability
*** the overall atmospheric temperature profile
stability
absolutely unstable> When you ELR is greater then air molecule (5.5/1000 feet)>>>>> (fast)
conditionally unstable-When the ELR is in between 5.5 and 3.3
absolutely stable-when ELR is below 3.3***if air is saturated it is unstable
stable air
air resist change
stability is enhanced by:
radiation of cooling of the earth surface after sunset
cooling air mass from below as it traverses a colder surface
sinking air
*** promotes cool dense stable air close to the ground
unstable air
once forced upward initially air rises
-instability is enhanced by:
intense solar heating
heating of an air mass from below as it moves over a warmer surface
forceful lifting of air( Mountain)
upward motion with surface air convergence

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