Geography Lab2
Location and Temp Agulhas current
...
Location and Temp Oyashio current
...
Location and West Wind Drift current
...
When a front passes through a region, abrupt weather changes normally occur. With the passing of a cold front, we note the following:
1. The temperature decreases sharply. 2. Winds shift from southerly, ahead of the front, to northwesterly, following it (in the Northern Hemisphere). 3. The front is in a pressure trough, so pressure falls as the front approaches and rises after it passes. 4. Generally clear skies ahead of the front are replaced by cloudiness and precipitation at the front - to be replaced again by clear skies after the front passes.
Check out the globe on the bottom of page
125
What is the wet adiabatic rate
3.3 F/1000
What is the normal lapse rate
3.5 F/1000 feet
Calculate temperature at various elevations using the normal lapse rate (for still air)
3.5 degrees F/ 1000 ft
What is the normal lapse rate
3.5 degrees F/1000 ft.
What is the dry adiabatic rate
5.5 F/1000 feet
What is a pressure gradient
Air flows from high to low
What happens at lifting condensation level
As a parcel of unsaturated air rises, it cools at the dry adiabatic rate. If the air mass rises high enough, it cools to the dew point temp, the air saturates, condensation begins, clouds form. This is the flat base we see on clouds
Before a warm front
Decreasing pressure Winds south to southeast Cool Temps Cirrus, cirrostratus, altostratus, nimbostratus Light to moderate, increasing rain
Time formula
Distance/Rate
Find the lapse rate if the temp is 68 degrees at 0 ft (sea level) at 10,064 ft
Find the elevation difference = 10,064 ft Set up ratio for cross multiplication: (Temp) 3.5 = x (Elev) 1000 = 10,064 Solve (10,064) 3.5 / 1000 = 35.22 F Remember: if calculating from a higher elevation, subtract degrees from starting temp and if calculating from a lower elevation, add degrees to starting temp So for this problem we are calculating from a higher elevation of 10,06 ft from 0 ft. 68 - 35.22 = 32.78 or 33 degrees at 10,064 ft (higher altitudes it will be cooler, lower altitudes, warmer)
Find the lapse rate if the temp is 68 degrees at 0 ft (sea level) at 1280 ft
Find the elevation difference = 1280 ft Set up ratio for cross multiplication: (Temp) 3.5 = x (Elev) 1000 = 1280 Solve (1280) 3.5 / 1000 = 4.48 F Remember: if calculating from a higher elevation, subtract degrees from starting temp and if calculating from a lower elevation, add degrees to starting temp So for this problem we are calculating from a higher elevation of 1280 ft from 0 ft. 68 - 4.48 = 63.52 at 1280 ft (higher altitudes it will be cooler, lower altitudes, warmer)
Find the lapse rate if the temp is 68 degrees at 0 ft (sea level) at 14,494 ft
Find the elevation difference = 14,494 ft Set up ratio for cross multiplication: (Temp) 3.5 = x (Elev) 1000 = 14,494 Solve (14,494) 3.5 / 1000 = 50.73 F Remember: if calculating from a higher elevation, subtract degrees from starting temp and if calculating from a lower elevation, add degrees to starting temp So for this problem we are calculating from a higher elevation of 14,494 ft from 0 ft. 68 - 50.73 = 17.27 or 17 degrees at 14,494 ft (higher altitudes it will be cooler, lower altitudes, warmer)
Find the lapse rate if the temp is 68 degrees at 0 ft (sea level) at Death Valley - -282 ft below sea level
Find the elevation difference = 282 ft Set up ratio for cross multiplication: (Temp) 3.5 = x (Elev) 1000 = 282 Solve (282) 3.5 / 1000 = .987 F Remember: if calculating from a higher elevation, subtract degrees from starting temp and if calculating from a lower elevation, add degrees to starting temp So for this problem we are calculating from a lower elevation of -282 ft from 0 ft. 68 + .987 = 68.987 or 69 degrees F at -282 ft below sea level (higher altitudes it will be cooler, lower altitudes, warmer)
How to find the lapse rate if temp is 65 degrees at 3000 ft, what will the temp be at 7000 ft
Find the elevation difference = 4000 ft Set up ratio for cross multiplication: (Temp) 3.5 = x (Elev) 1000 = 4000 Solve (4000) 3.5 / 1000 = 14 F Remember: if calculating from a higher elevation, subtract degrees from starting temp and if calculating from a lower elevation, add degrees to starting temp So for this problem we are calculating from a higher elevation of 7000 ft from 4000 ft. 65 - 14 = 51 at 7000 ft (higher altitudes it will be cooler, lower altitudes, warmer)
Cold fronts
Heavy rainfall, decreasing temperatures, decreasing humidity, and changing wind directions are associated with passage of a cold front.
Continental Tropical
Hot and Dry
How can relative humidity change if temp stays the same
If temperature stays the same, relative humidity changes as water vapor enters or leaves the air.
After cold front
Increasing pressure North Northwest cold temps Cumulus, altostratus Moderate-light, decreasing precipitation
Warm fronts
Light to moderate rain, warmer temperatures, increasing humidity, and changing wind directions follow passage of a warm front
Location and Temp of California Current
Location: The California current flows along the West Coast of the United States Temp: cool
Know the location and T° of Humbolt
Location: north along the west coast of South America from the southern tip of Chile to northern Peru. Known as the Peru current Temp: warm
Location and Temp of Gulf Stream
Location: originates at the tip of Florida, and follows the eastern coastlines of the United States and Newfoundland before crossing the Atlantic Ocean. Temp: warm
Location and Temp of North Atlantic Drift
Location: warm ocean current in the northern part of the Atlantic Ocean. A continuation of the Gulf Stream Temp: Warm
Identify marine or continental location based on monthly temperatures/annual temp ranges
Marine West Coast - Moderate temps - avg summer temp 60 to 70 degrees and winter temps 35 to 45 degrees - moderate annual temp range Humid Continental - Dramatic swings in temp, huge variability day to day, cold waves, heat waves, blizzards, thunderstorms, tornadoes, etc. Summer temps average mid 70's mild and brief. But winter temps is between 10 to 25 degrees with 1 to 5 months below freezing, long, dark, very cold. Huge annual temp ranges
Distance formula
Rate (Time)
Location and Temp Benguela current
Temp:
Location and Temp of Brazil current
Temp: warm
On page 96, you can see the warm currents in the red and cool currents in blue. What do you notice
Warm currents seem to go between 30 degrees north and south plus the north Atlantic drift. Cold currents are beyond that
Dry bulb - Wet bulb =
Wet bulb depression
What is albedo
ability of a surface to reflect radiation
Relative humidity percentage
absolute humidity/capacity x 100
How to calculate "mean" temp
add temps and divide by total number of temps
Dry bulb
air temp
The prefix is the
altitude
Clouds are classified by two characteristics
altitude and shape
What is specific heat?
amount of energy needed to raise the temp of 1 gram of any material 1 degree C
Wet bulb
amount of evaporation - how much room is in the air for water vapor to evaporate
What is insolation
amount of radiation energy received from the sun to drive Earth's processes
What is capacity?
amount of water vapor in grams an air parcel can hold at a given temp
What is absolute humidity
amount of water vapor in grams present in a given parcel of air
Trade Winds
arrows from the sub tropical high converging at the equator
Westerlies
arrows from the subtropical high between 40 to 60 degrees latitude N and S
Air is heated from the ground up how
by long wave radiation emitted from the earth not by short wave insolation
How are ocean currents set in motion
by the trade winds blowing across the equator from the east towards the west
Be able to locate the location of a warm and cold front on an isobar map
can you do this?
Know where to find the cold front, warm front, cold air mass, warm air mass, and the direction of movement on a map and cross-section of a mature midlatitude cyclone
can you do this?
Polar air mass
cold
The air mass with the lowest humidity would be
cold
What is high pressure
cold air sinking to an area of higher external pressure; diverges
Continental Polar
cold and dry
Adiabatic heating and cooling is one of the processes that creates
condensation and precipitation
Air masses
continental, marine, tropical, polar
Marine Polar
cool and wet
This causes the air mass to
cool by expansion
Increasing temps causes the relative humidity to _____ and what happens to condensation?
decrease; it ends
Continental air mass
dry
Sub tropical highs
hatch marks along the 30 degree latitude line N and S
What is sensible heat
heat (energy) you feel
ITCZ
heavy line along the equator
How about a cement sidewalk
high
What about a greek village with white painted houses
high
Would antarctica be a high or low albedo?
high
Cirrus, what's the altitude, shape, and weather
high, no shape, wispy high clouds of ice crystals stable conditions
Cirrocumulus
high, rounded and puffy, approaching strorm
How to calculate the temp "range"
highest temp minus lowest temp
Marine air mass
humid
The air mass may reach dew point temp depending on
humidity and degree of cooling
What is the coriolis effect
in the Northern Hemisphere high pressure = diverging, clockwise low pressure = converging, counterclockwise in the Southern Hemisphere high pressure = diverging, counter clockwise low pressure - converging, clockwise
What happens to the air mass as it rises
it expands as it increases altitude and external pressure decreases
The results of specific heat for land and water
land (continental interiors) experiences extreme temp ranges during day or over a year water (coastal) experiences lower temp ranges during day or over a year
Land heats and cools faster than water. Why?
land has lower specific heat water has higher specific heat
Why is the rate of cooling slowed above lifting condensation level?
latent heat is released when water vapor condenses
With a warm air front, what is different
lesser magnitude
Can you identify the source regions for air masses for North America on a map?
let me know
The elevation where this occurs is called
lifting condensation level
A freshly plowed field with dark brown soil
lo
Would lava flow in Hawaii be hi or lo
low
Would the amazon river be hi or lo
low
cumulus
low, round and puffy, fair weather
stratocumulus
low, round and puffy, stretchy, drizzle
Cirrostratus
low, sheet like, indicate approaching storms
Nimbostratus
low, sheetlike, gentle steady rain
Stratus
low, sheetlike, overcast
What are some low albedo surfaces
mature forests, dark soil, dark fields, dark rocks, rough surfaces
Altocumulus
mid, puffy and round, settled weather, stable
Altostratus
mid, sheetlike, changing weather - unstable
What are the 4 factors of water
mobile transparent higher evaporation higher specific heat
Cumulonimbus
no altitude, tall vertical thunderclouds, produce heavy rain, hail, tornadoes
Stratus
prefix Low (before 6500
Alto
prefix Middle (6500 to 20,000 ft)
Cirrus
prefix high (20,000 ft)
What are the primary means for transporting surplus energy from the tropics to the deficit areas at the poles
pressure, wind, and ocean circulation systems
What is relative humidity
ratio of water vapor present to the total amount of vapor the air mass can hold
When an air mass comes in contact with a barrier, such as a mountain, it is forced to
rise
When do we use the wet adiabatic rate
rising air masses that have cooled to dew point
When do we use the dry adiabatic rate
rising air masses that have not cooled to dew point
If this happens, the air mass will become
saturated
Why don't all geographic locations not receive the same amount of insolation
seasons - shift of direct rays in tropics, 24 hrs day/night poleward angle of the rays duration of daylight atmospheric conditions albedo
The suffix is the
shape
Between warm and cold fronts
small decrease in pressure, then small increase southwest winds warm temps Cumulus, cumulonimbus No rain then heavy rain prior to cold front
What are some high albedo surfaces
snow, ice, sand, deserts, light vegetation, smooth surfaces, light surfaces
What are the 4 factors of land
solid opaque less evaporation lower specific heat
When do we use the normal lapse rate
stratified air - air that is not rising
Nimubus
suffix any could that is precipitating
Cumulus
suffix rounded and puffy
Humidity is based on
temp
What is dew point
temperature where relative humidity is 100% AND to which a given air mass must cool in order for condensation to occur
As the air mass descends, what happens
the opposite. Increasing external pressure compresses the air mass and causes warming.
What is leeward
the side of the mountain where air is sinking and warming; no precipitation
What is winward
the side of the mountain where the air is rising, cooling, and precipitating
Wind direction is based on
the source region of the air - which direction it is coming from
What happens when the currents hit a barrier
the water is deflected to the right in the northern hemisphere and to the left in the southern hemisphere by the Coriolis Effect see pg 96
You only use the wet adiabatic rate on which side of the mountain? .
the winward side, above lifting condensation level (LCL)
Ocean currents are responsible for
transferring surplus energy stored along the equator to deficit areas at the poles
Fronts occur where
two air masses of different temps meet. A low pressure cell forms where the air masses meet due to mixing. Around the low pressure cell in the northem hemisphere, the air will circulate counterclockwise around the cell due to Coriolis. This allows the cold air to move into the warm air sector and warm air to move into the cold air sector. Eventually, the cold front will overtake the warm front, and the cyclone will end.
The air mass with the highest humidity would be
warm
Tropical air mass
warm
Which has a high capacity, warm air mass or cold air mass
warm
What is low pressure
warm air rising to an area of lower external pressure; converges
Marine Tropical
warm and wet
There is more evaporation over water or land
water
What happens to relative humidity if temp increases or decreases
when temp decreases, humidity increases when temp increases, humidity decreases the warmer it is, the greater capacity for water vapor in the air
