4.5 - 4.9 global wind patterns, solar radiation/earths seasons, earths geography/climate, el nino/ el nina

uneven warming pattern

1. variation in angle sun’s ray hits earth

2. variation in surface area sun’s ray is distributed

3. albedo

equator

receives sunlight at 90 degree angle

albedo

percentage of incoming sunlight reflected off surface

perpendicular

region near equator (tropics) sun’s ray hits earth at a _____ angle

travels a shorter distance to equator than other latitudes

more solar energy than mid-latitudes and polar regions

oblique

at higher and lower latitudes, sun’s ray hit at an ____ angle

smaller surface

when sun’s ray hits equator, solar energy is distributed over ____ ____ than near poles

more solar energy/square meter

white surface

__ ___ has higher albedo (reflects more solar energy) than black surface, stays cooler

ex. dense forest = low albedo

snow covered polar regions = high albedo

axis of rotation

__ __ __ is tilted at 23.5 degrees, so amount of solar energy reaching various latitudes shifts over course of year

earth’s tilt

an orbit around the sun causes seasonal changes in temperature and precipitation

more pronounced when northern hemisphere is toward sun and southern hemisphere is away, and vice versa

december solstice

northern hemisphere is tilted AWAY from sun, shortest day of year

at tropic of capricorn at 23.5 degrees south latitude

NH = winter

SH = summer

march equinox

sun is directly over equator, entire earth gets 12 hours day/night

NH = spring

SH = fall

june solstice

northern hemisphere is tilted TOWARD sun, longest day of year

over tropic of cancer at 23.5 north latitude

NH = summer

SH = winter

september equinox

sun is overhead equator, everywhere has 12 hours day/night

NH = fall

SH = spring

axis of rotation’s tilt

causes seasons

solstice

longest/shortest day of year

earth’s axis tilted away/toward sun

equinox

day and night are EQUAL in length

adiabatic cooling

cooling effect of reduced pressure on air as it rises higher in atmosphere and expands

saturation point

maximum amount of water vapor in air at given temperature

latent heat release

release of energy when water vapor in atmosphere condenses in liquid water

adiabatic heating

heating effect of increased pressure on air as it sinks toward surface of earth and decreases in volume

atmospheric convection current

global patterns of air movement initated by unequal heating of earth

atmospheric convention current

major contributor to different climates and move air and moisture around globe

cycle of air

warming at earth’s surface causes air to rise → lower pressure, adiabatic cooling, latent heat release

cool air at top of atmosphere is displaced horizontally then sinks

experiences adiabatic heating + moves horizontally

intertropical convergence zone

ITCZ

latitude that receives MOST intense sunlight, causes ascending branches of 2 hadley cells to converge

hadley cell

convection current in atmosphere that cycles between equator and 30 deg N and 30 deg S

trade wind

caused by hadley cells

hadley cell

atmospheric convention current between 30 deg N and 30 deg S

solar energy warms humid air in tropics → rises → cools below saturation point

air sinks to 30 deg N and 30 deg S → warmed by adiabatic heating

water vapor condenses into clouds and precipitation

CAUSES DESERT ENVIRONMENTS TO DEVELOP

polar cell

convection current in atmosphere formed by air

rises at 60 deg N and 60 deg S

sinks at 90 deg N and 90 deg S

ferrell cell

convection current in atmosphere between hadley cells and polar cells

air currents

driven by nearby hadley cells and ferrell cells

warm air from hadley cells move towards poles

cool air from ferrell cells move towards equator

westerlies winds

caused by ferrell cells

atmospheric convection current

responsible for locations of rainforest, deserts, grasslands bc determine patterns of temperature and precipitation

north to south

atmospheric convection currents cause air to move ___ to ___

but is DEFLECTED because earth is rotating

faster

as earth rotates, surface moves ___ at equator than mid-latitude/polar regions

faster rotation speeds at equator cause objects moving north or south to deflect

coriolis effect

deflection of object’s path due to rotation of earth

prevailing winds

produced by combination of atmospheric convection currents and coriolis effect

rain shadow effect

humid winds blowing inland from ocean meets MOUNTAIN RANGE

windward (wind facing) side of mountains: air rises and cool (adiabatic cooling), large amounts of water vapor condense to form clouds and precipitation

leeward side of mountains: dry air falls and warms (adiabatic warming), causes much drier conditions = rain shadow

ocean currents

driven by combination of temperature, gravity, prevailing winds, salinity, coriolis effect, continent location

warm water

expands and rises

raises surface of water in tropics to be 3 inches higher than mid-latitudes

slight slope + gravity causes water to flow AWAY from equator

gyre

large scale pattern of water circulation moving clockwise in NH and counterclockwise in SH

gyre

redistribute heat in ocean causing cold water from polar regions to move along west coast of continents

cool air above water brings cooler temperatures to these continents

gyre

driven by trade winds in tropics and westerlies in mid-latitudes

california current

causes coastal areas of california to have cooler temperatures than areas of similar latitudes along easy coast of us

upwelling

upward movement of ocean water toward surface because of diverging currents

west coast

upwelling occurs along __ __ of most continents

when surface currents diverge, deeper waters rise to replace water that has moved away

upwelling

brings nutrients from ocean bottom that supports producers → support large populations of fish

HIGHLY PRODUCTIVE ECOSYSTEMS

thermohaline circulation

oceanic circulation pattern that drives mixing of surface water and deep water

takes hundreds of years to complete

thermohaline circulation

crucial for moving heat and nutrients around globe

thermohaline circulation

driven by surface waters that contain unusually large amounts of SALT

mixes water of ALL oceans

gulf stream

originates in gulf of mexico but flows toward western europe + brings warmer water/temperature to cold places

englands average winter temperature is 20 deg celsius warmer than newfoundland canada (at a similar latitude)

el nino southern oscillation

ENSO

reversal of wind and water currents in south pacific between south america and australia/southeast asia

caused by shift in ocean currents

coast of south america

shifts regularly from el nino (warmer, rainier) to la nina (cooler, drier) conditions along ___ of __ ___

normal year

trade winds push warm surface waters from coast of SA towards australia and SE asia

promotes upwelling of water near SA

drier conditions in SA

wetter, warmer conditions on australia and SE asia

el nino southern oscillation

trade winds near SA weaken → warm equatorial water from western pacific (australia/SE asia) move toward west coast of SA

warm water/air suppresses upwelling off peru coast + decreases productivity there, reduces fish populations near coast

ENSO consequences

reduces upwelling off coast of SA → decreases nutrients, productivity, fish populations, income

ENSO consequences

causes warmer and wetter conditions in americas → increases flooding

ENSO consequences

causes cooler, drier conditions in australia and SE asia → drought

poor crop yields → death in developing countries

ENSO consequences

decreased hurricane activity in atlantic

ENSO consequences

weakened monsoon activity in india + SE asia

la nina

stronger than normal trade winds

east to west, warmer/rainier in australia/SE asia

increased upwelling off coast of SAS → cooler conditions, extra fisheries