Lec 3- enviro variation Flashcards
Climate
causes different environments
- round earth
- rotation
- tilt at diff angle twd earth (23 tilted)
- orbits
geography of earth
almost round and dived into
latitudinal lines (W and E = parallel)
longitudinal (N and S = meridians)
Equator
0 degree
widest point
hottest
northern hemisphere
latitudes north of equator
southern hemisphere
latitudes south of equator
North pole
90 degrees latitude
arctic circle
66 degrees latitude
34 degrees N
- sun never sets 1 day of the yr
Tropic of Cancer
turning point
23 degrees 26 degrees N
summer solstice
Tropic of Capricorn
23 degrees 26 degrees S
winter solstice
Antarctic circle
66 degrees latitude
34 degrees S
South pole
90 degrees latitude
south
Sun
main driver of climate
w/o sun means no life exists
energy shapes biotic and abiotic
variation based on position
weather
day to day state of atmosphere
over span of days
- rain, snow, wind
climate
long term avgs of weather
historical record
- quantitative climate properties- avg sum of precipitation per yr or avg temp per yr
- qualitative- temperate
Solar angle of incidence
- diff parts of planet receive diff amounts of solar energy
- depends on latitude and associated angle of incidence
- equator around 90 degrees solar angle (straight overhead)
- energy hits smaller surface compared to higher latitudes
- distance b/w sun and earth is shorter
- poles less that 90 degrees (never overhead)
- energy scattered across larger surface compared to equator
- distance b/w sun and earth is longer
what drives major climatic systems?
solar angle of incidence
- diff in solar angle of incidence resulting in diff amounts of solar radiation received
global air circulation
uneven distribution of solar energy per unit area across latitude acts like a motor that sustains major air circulation across planet
Hadley Cells
- form due to warm air rising, cooling and forming condensation (rain) at equator
- 30 degrees latitude. airmasses descend, warm up and absorb moisture
- close to equator
- Monsoons
- deserts and rainforests
Ferrel Cells
30-60 degrees N and S
- not maintained by warming and cooling effects
- caused by strong energy of other cells
- YEG @ 53 degrees
Polar Cells
- form due to warming and cooling of air
- air masses rise at about 60 degrees and cool down closer to poles where they descend as very cold air
Coriolis effect and winds
above earths surface
- atmospheric masses are move at a tilt bc of Coriolis effect
N: deflected to the right of direction of travel (looking at flat map: down and to left)
S: deflected to the left
(looking at map: up and to the left)
Northeast trade winds
b/w 0-30 degrees N
- b/w equator and tropic of cancer
- from hadley
Southeast trade winds
b/w 0-30 degrees S
- b/w equator and tropic of capricorn
Westerlies
winds
30-60 degrees N and S
Polar easterlies
winds from 60 degrees N to N Pole
and 60 degrees S to S Pole
Northern Hemisphere and Coriolis
storms spin CCW
fluids from high-pressure sys pass low-pressure sys to the right
1. winds rushes to the low-pressure eye of hurricane
2. coriolis effect tugs wind to the right
3. entire storm rotates CCW
Southern Hemisphere and Coriolis
storms spin CW
- currents deflected to the left
Topographic effects
solar radiation drives 3 main types of climate cells
- large topography and water bodies influence climate-albeit at more regional scale
windward side of mountain has warm, moist air and lush veg
air rises and cools and condenses and rain
dry air goes down on leeward side of mountain
rain shadow
np veg
Wind-driven ocean currents from ocean gyres
water masses move too = currents
- vertically and horizontally
- exchange of water masses, energy, salts and and nutrients
Gyres
horizontally circulating
major water currents in oceans
driven by winds, Coriolis and position/distance from land masses
