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SOAR 2007SOAR 2007
Energy and TemperatureEnergy and Temperature
Energy & TemperatureEnergy & Temperature Insolation
Spectrum Distribution with latitude Distribution with albedo
Interaction with Air, Land & Water Reflected Absorbed by atmosphere Absorbed by land Absorbed by water
Effect of insolation Heating & temperature
Insolation Spectrum Distribution with latitude Distribution with albedo
Interaction with Air, Land & Water Reflected Absorbed by atmosphere Absorbed by land Absorbed by water
Effect of insolation Heating & temperature
Temperature Scales (Again!)Temperature Scales (Again!)
Celsius 0 - fresh water freezes 100 - fresh water boils at 1013.2 hPa (1
atm)
Kelvin Based on gases
TC + 273 = TK
Fahrenheit – used only in US 0 ~ salt water freezes 100 ~ human body temp.
TC = (5/9)(TF - 32)
TF = (9/5)TC + 32)
Celsius 0 - fresh water freezes 100 - fresh water boils at 1013.2 hPa (1
atm)
Kelvin Based on gases
TC + 273 = TK
Fahrenheit – used only in US 0 ~ salt water freezes 100 ~ human body temp.
TC = (5/9)(TF - 32)
TF = (9/5)TC + 32)
Celsius – Fahrenheit touch
points:
-40 C = -40 F
16 C = 61 F
28 C = 82 F
Celsius – Fahrenheit touch
points:
-40 C = -40 F
16 C = 61 F
28 C = 82 F
PressurePressure
Temperature C
Temperature C
-273-273
Plots for different gases meet at -273 C
Plots for different gases meet at -273 C
Temperature Scales
Temperature ScalesCelsius –
Fahrenheit touch points:
28C ≈ 82F
16C ≈ 61F
-40C = -40F
Celsius – Fahrenheit touch
points:
28C ≈ 82F
16C ≈ 61F
-40C = -40F“At 40
below it doesn’t matter!”
Atmospheric “Windows”Atmospheric “Windows” Solar Radiation
air transparent to some (visible, radio, some IR)
opaque to others (some IR & UV, all X- & -rays)
Solar Radiation air transparent to some (visible, radio, some IR)
opaque to others (some IR & UV, all X- & -rays)
Solar Radiation & LatitudeSolar Radiation & Latitude Latitude
Latitudes close to equator get more annual sun Tropics
23.5 N - Tropic of Cancer 23.5 S - Tropic of Capricorn
Polar Regions 66.5 N – Arctic Circle 66.5 S – Antarctic Circle
Latitude Latitudes close to equator get more annual
sun Tropics
23.5 N - Tropic of Cancer 23.5 S - Tropic of Capricorn
Polar Regions 66.5 N – Arctic Circle 66.5 S – Antarctic Circle
Sun directly overhead on
solstice
Sun directly overhead on
solstice
Sun does not set (or rise) on
solstice
Sun does not set (or rise) on
solstice
Sun Angle & LatitudeSun Angle & Latitude Insolation depends on sun angle. Insolation depends on sun angle.
Sun Angle Through the Year
0
30
60
90
120
J F M A M J J A S O N D
Ang
le a
bove
Hor
izon
At the Equator, the noontime sun goes from 23.5 South of the zenith to 23.5 North of the zenith.
All days have 12 hours of daylight.At the Tropic of Cancer, the noontime sun is directly overhead
on the northern summer solstice.In Canton, the noontime sun goes from 45-23.5= 21.5 above the horizon to 45-23.5= 68.5 above the horizon.At the Arctic Circle, the sun goes from being just at the horizon
on the winter solstice to 47 above the horizon.
Point of sunrise & sunset changes by
68° From azimuth 56° to 124° (90° is east)
Highest angle changes by
47° from 21.5°
to 68.5°
No-shadow days!
Insolation in CantonInsolation in Canton Summer sun 21.5 Summer sun 21.5
~700 W/m2 from sun reaches
surface
~700 W/m2 from sun reaches
surface
~665W falls on one m2 in
Canton in summer
~665W falls on one m2 in
Canton in summer
~500W falls on one m2 in Canton in
spring & fall
~500W falls on one m2 in Canton in
spring & fall
~260W falls on one m2 in
Canton in winter
~260W falls on one m2 in
Canton in winter
Insolation & LatitudeInsolation & Latitude
Insolation & LatitudeInsolation & Latitude Tropics
energy surplus Poles
energy deficit Energy must betransported to poles
Tropics energy surplus
Poles energy deficit
Energy must betransported to poles
Latitude & TemperatureLatitude & Temperature Temperature plots of data from
worldclimate.com Temperature plots of data from
worldclimate.com
Temperatures at Diff erent Latitudes
0
10
20
30
40
J F M A M J J A S O N D
Deg
rees
C
Venice, I taly 45N
Pakanbaru, I ndonesia, 0S
Shuwaikh, Kuwait, 30N
Reflected Radiation -- AlbedoReflected Radiation -- Albedo Different surfaces reflect differently Different surfaces reflect differently
Melting ice & snow increases
absorption, enhances heating
Melting ice & snow increases
absorption, enhances heating
Melting sea ice increases absorption,
enhances heating
Melting sea ice increases absorption,
enhances heating
“Ice-Albedo Effect”
“Ice-Albedo Effect”
Insolation on Earth’s SurfaceInsolation on Earth’s Surface Distributed by latitude & vegitation Distributed by latitude & vegitation
Deserts get > 200 W/m2
Deserts get > 200 W/m2
Rainforests get less due to clouds
Rainforests get less due to clouds
InsolationInsolation Short wave radiation
visible light emitted by Sol (the sun) absorbed by land & water not absorbed by air
Long wave radiation infrared (IR)
emitted by Earth absorbed by air,
land & water
Short wave radiation visible light
emitted by Sol (the sun) absorbed by land & water not absorbed by air
Long wave radiation infrared (IR)
emitted by Earth absorbed by air,
land & water
Simplified Energy BudgetSimplified Energy BudgetShortwave radiation from sun (light)
absorbed by Earth (land & water)Earth heats & emits longwave radiation
Shortwave radiation from sun (light) absorbed by Earth (land & water)
Earth heats & emits longwave radiation
Top of the atmosphere receives 1372 W/m2 - solar constant
Top of the atmosphere receives 1372 W/m2 - solar constant10 W = power to lift 1 kg 1 meter in 1 second10 W = power to lift 1 kg 1 meter in 1 second
Energy BudgetEnergy Budget Insolation – incoming solar radiation
reflected & absorbed
Insolation – incoming solar radiation reflected & absorbed
~30% reflected~30% reflected
Energy BudgetEnergy Budget Insolation – incoming solar radiation
reflected & absorbed
Insolation – incoming solar radiation reflected & absorbed
~30% reflected~30% reflected
Outgoing shortwave
reflected from clouds and
deserts, absorbed by
ocean & forests
Outgoing shortwave
reflected from clouds and
deserts, absorbed by
ocean & forests
Energy BudgetEnergy Budget Insolation – incoming solar radiation
reflected & absorbed
Insolation – incoming solar radiation reflected & absorbed
~30% reflected~30% reflected
~51% absorbed by surface~51% absorbed by surface
~19% absorbed by air & clouds
~19% absorbed by air & clouds
~70% re-radiated
~70% re-radiated
Energy BudgetEnergy Budget Insolation – incoming solar radiation
reflected & absorbed
Insolation – incoming solar radiation reflected & absorbed
~51% absorbed by surface~51% absorbed by surface
Outgoing longwave
radiated by surfaces
Outgoing longwave
radiated by surfaces
~70%
re-radiated
~70%
re-radiated
Energy BudgetEnergy Budget Insolation
Sun’s incident energy drives air motions (energy from deep interior adds a tiny bit)
Distribution of Sunlight Reflection from clouds, landscape Absorption by atmosphere Absorption by surface
Albedo = ratio of sunlight reflected Earth: 0.367 Moon: 0.113 Mars: 0.15 Venus: 0.84
Insolation Sun’s incident energy drives air motions
(energy from deep interior adds a tiny bit)
Distribution of Sunlight Reflection from clouds, landscape Absorption by atmosphere Absorption by surface
Albedo = ratio of sunlight reflected Earth: 0.367 Moon: 0.113 Mars: 0.15 Venus: 0.84
Energy DistributionEnergy Distribution Convection – hot stuff moves Conduction – hot stuff heats neighbors Radiation – heat moves as IR radiation
Convection – hot stuff moves Conduction – hot stuff heats neighbors Radiation – heat moves as IR radiation
Insolation: 1,373 W/m2Insolation: 1,373 W/m2
30% Reflected by atmosphere &
surface
30% Reflected by atmosphere &
surface20% Absorbed by
atmosphere20% Absorbed by
atmosphere
50% Absorbed by Earth’s surface
50% Absorbed by Earth’s surface
Most solar energy comes in as light (shortwave
radiation)
Most solar energy comes in as light (shortwave
radiation)
Insolation: 1,373 W/m2Insolation: 1,373 W/m2
30% Reflected by atmosphere &
surface
30% Reflected by atmosphere &
surface20% Absorbed by
atmosphere20% Absorbed by
atmosphere
50% Absorbed by Earth’s surface
50% Absorbed by Earth’s surface
Most solar energy comes in as light (shortwave
radiation)
Most solar energy comes in as light (shortwave
radiation)
Surface
Air Clouds
Reflection of sunlight
Reflection of sunlight
Energy Emitted by Planet EarthEnergy Emitted by Planet Earth
30% reflected directly to
space
30% reflected directly to
space
% of total insolation% of total insolation
70% emitted
as IR
70% emitted
as IR
Energy Flow from SurfaceEnergy Flow from Surface7% conducted to air7% conducted to air
20% radiated as
IR (longwave)
20% radiated as
IR (longwave)
~ 50% of total
insolation absorbed by
surface
~ 50% of total
insolation absorbed by
surface
23% transferred by water23% transferred by water
Energy Absorbed by Atmosphere
Energy Absorbed by Atmosphere
20% from Sun20% from Sun7% conducted from surface7% conducted from surface
23% transferred by water23% transferred by water8% radiated by
surface8% radiated by surface
% of total insolation% of total insolation
Energy Absorbed by Atmosphere
Energy Absorbed by Atmosphere
20% from Sun20% from Sun7% conducted from surface7% conducted from surface
23% transferred by water23% transferred by water8% radiated by
surface8% radiated by surface
% of total insolation% of total insolation
Urban Heat IslandsUrban Heat Islands Structures and pollution increase heat Structures and pollution increase heat
Urban Heat IslandsUrban Heat Islands May be giving false increases in global
temperature since most weather stations are at airports in urban areas!
May be giving false increases in global temperature since most weather stations are at airports in urban areas!
Energy Absorbed by Atmosphere
Energy Absorbed by Atmosphere
20% from Sun20% from Sun7% conducted from surface7% conducted from surface
23% transferred by water23% transferred by water8% radiated by
surface8% radiated by surface
% of total insolation% of total insolation
Energy Transfer by WaterEnergy Transfer by Water Latent heat effects weather Latent heat effects weather
Evaporating water absorbs energy
from water, cooling it.
Evaporating water absorbs energy
from water, cooling it.
Condensing water releases energy to
air, heating it.
Condensing water releases energy to
air, heating it.
Energy Absorbed by Atmosphere
Energy Absorbed by Atmosphere
20% from Sun20% from Sun7% conducted from surface7% conducted from surface
23% transferred by water23% transferred by water8% radiated by
surface8% radiated by surface
% of total insolation% of total insolation
WesterliesWesterlies
WesterliesWesterlies
NE TradesNE Trades
SE TradesSE Trades
EasterliesEasterlies
EasterliesEasterlies
Moist air rising stormy
Moist air rising stormy
Moist air rising stormy
Moist air rising stormy
Dry air falling Arid
Dry air falling Arid
Dry air falling Arid
Dry air falling Arid
Moist air rising stormy
Moist air rising stormy
Atmospheric CirculatonAtmospheric Circulaton Ground conducts heat to adjacent
air Heated air rises Troposphere cools with altitude
Environmental lapse rate
Ground conducts heat to adjacent air
Heated air rises Troposphere cools with altitude
Environmental lapse rate Inversion = warmer air aloft
Inversion = warmer air aloft
Energy Absorbed by Atmosphere
Energy Absorbed by Atmosphere
20% from Sun20% from Sun7% conducted from surface7% conducted from surface
23% transferred by water23% transferred by water8% radiated by
surface8% radiated by surface
% of total insolation% of total insolation
Greenhouse EffectGreenhouse Effect Light from sun gets absorbed by Earth Earth radiates infrared
Light from sun gets absorbed by Earth Earth radiates infrared
Greenhouse EffectGreenhouse Effect Light from sun gets absorbed by Earth Earth radiates infrared
Light from sun gets absorbed by Earth Earth radiates infrared
Earth re-emits energy
absorbed from sunlight as
infrared
Earth re-emits energy
absorbed from sunlight as
infraredinfraredinfrared
Greenhouse Effect
Greenhouse Effect
IR gets absorbed by atmosphere Air heats Air absorbs more
water Moist air absorbs more IR & heats more absorbs more
water
IR gets absorbed by atmosphere Air heats Air absorbs more
water Moist air absorbs more IR & heats more absorbs more
water
Global WarmingGlobal Warming
Increasing greenhouse gases increases absorption of longwave (IR) radiation
by ground
Increasing greenhouse gases increases absorption of longwave (IR) radiation
by ground
Increasing greenhouse gases decreases
longwave (IR) radiation lost to space
Increasing greenhouse gases decreases
longwave (IR) radiation lost to space
Venus: Greenhouse gone wild!Venus: Greenhouse gone wild!
The difference between Earth and
Venus!
Complete Energy BudgetComplete Energy Budget
Sunlight & TemperatureSunlight & Temperature Noon not warmest time of day Solstice not warmest time of year
Temperature waits for surface to heat air!
Noon not warmest time of day Solstice not warmest time of year
Temperature waits for surface to heat air!
Insolation on Land and WaterInsolation on Land and Water Land
Light heats surface, some downward conduction no downward transmission or convection
Conduction to subsurface very slow Water
Surface molecules evaporate, cooling surface Light penetrates to depths, heats subsurface Heats slowly due to high specific heat Convection moves heat across surface and
beneath surface … currents
Land Light heats surface, some downward
conduction no downward transmission or convection
Conduction to subsurface very slow Water
Surface molecules evaporate, cooling surface Light penetrates to depths, heats subsurface Heats slowly due to high specific heat Convection moves heat across surface and
beneath surface … currents
Land and WaterLand and Water Water distributed heat more than
land Water distributed heat more than
land
Energy Absorbed by WaterEnergy Absorbed by Water Specific Heat
Energy absorbed/released to change temp. Latent Heat
Energy needed to change phase (substance remains at same temperature)
Specific Heat Energy absorbed/released to change temp.
Latent Heat Energy needed to change phase (substance remains at same temperature)
Energy Absorbed by WaterEnergy Absorbed by Water Specific Heat
Energy absorbed or released to change temp.
Specific Heat Energy absorbed or released to change temp.
Substance Specific Heat (Joule/K/kg)
Air (50C) 1050
Iron or Steel 460
Lead 130
Glass 840
Quartz 762
Granite 804
Sandstone 1088
Shale 712
Soil (average) 1050
Wood (average)
1680
Ice 2100
Steam 2050
Water 4168
Raising 1 kg of water 1°C
absorbs 4,168 Joules
Raising 1 kg of water 1°C
absorbs 4,168 Joules
10 cm square cube
of water
10 cm square cube
of water
1 kg
4000 Joules ≈ energy to lift 400 kg or 900 lb 1 m4000 Joules ≈ energy to lift 400 kg or 900 lb 1 m
Energy Absorbed by WaterEnergy Absorbed by Water Latent Heat
Energy absorbed or released to change phase
Latent Heat Energy absorbed or released to change phase
Evaporating 1 kg of water
absorbs 2,257,000Joule
s
Evaporating 1 kg of water
absorbs 2,257,000Joule
s 10 cm square cube
of water
10 cm square cube
of water
1 kg
2,257,000 Joules ≈ energy to lift 225,700 kg or 507,000 lb 1 m2,257,000 Joules ≈ energy to lift 225,700 kg or 507,000 lb 1 m
Substance
Specific Heat (Joule/kg)
vaporization
fusion
Alcohol 879,000 109,000
Water 2,257,000 333,500
Land and WaterLand and Water Maritime climates milder than continental Maritime climates milder than continental
Seattle, 48 N, maritimeSeattle, 48 N, maritime
0
50
100
150
200
250
300
350
Janu
ary
Febru
ary
Mar
chApr
ilM
ayJu
ne July
Augus
t
Septe
mbe
r
Octobe
r
Novem
ber
Decem
ber
Rai
nfa
ll (
mm
)
-20
-10
0
10
20
30
40
Tem
p (
C),
Su
n A
ng
le (
(Deg
rees
/2)
Rainfall (mm) Solar Angle Average Temp-erature (C)
0
50
100
150
200
250
300
350
Janu
ary
Febru
ary
Mar
chApr
ilM
ayJu
ne July
Augus
t
Septe
mbe
r
Octobe
r
Novem
ber
Decem
ber
Rai
nfa
ll (
mm
)
-20
-10
0
10
20
30
40
Tem
p (
C),
Su
n A
ng
le (
(Deg
rees
/2)
Rainfall (mm) Solar Angle Average Temp-erature (C)
Minot, ND, 48 N, continental
Minot, ND, 48 N, continental
Monthly average temperature varies by 14 C in Seattle, 35 C in Minot
Monthly average temperature varies by 14 C in Seattle, 35 C in Minot
Atmospheric Water & WarmingAtmospheric Water & Warming Clouds & Rain
clouds reflect sunlight, shade ground so cloudy places should be cool …
moist air absorbs more IR than dry so humid places should stay warm …
Clouds & Rain clouds reflect sunlight, shade ground
so cloudy places should be cool …
moist air absorbs more IR than dry so humid places should stay warm …
0
50
100
150
200
250
300
350
Janu
ary
Febru
ary
Mar
chApr
ilM
ayJu
ne July
Augus
t
Septe
mbe
r
Octobe
r
Novem
ber
Decem
ber
Rai
nfa
ll (
mm
)
-20
-10
0
10
20
30
40
50
Tem
p (
C),
Su
n A
ng
le (
(Deg
rees
/2)
Rainfall (mm) Solar Angle Average Temp-erature (C)
0
50
100
150
200
250
300
350
Janu
ary
Febru
ary
Mar
chApr
ilM
ayJu
ne July
Augus
t
Septe
mbe
r
Octobe
r
Novem
ber
Decem
ber
Rai
nfa
ll (
mm
)
-5
0
5
10
15
20
25
30
35
40
45
Tem
p (
C),
Su
n A
ng
le (
(Deg
rees
/2)
Rainfall (mm) Solar Angle Average Temp-erature (C)
Monsoon rains cool Lhasa and Calcutta.Monsoon rains cool Lhasa and Calcutta.
Atmospheric Water & WarmingAtmospheric Water & Warming More evaporation
more clouds surface shaded surface cools atmosphere cools
More evaporation more clouds surface shaded surface cools atmosphere cools
Negative feedback prevents runaway warming
Negative feedback prevents runaway warming
Atmospheric Water & WarmingAtmospheric Water & Warming More evaporation
more clouds more IR absorption atmosphere warms
More evaporation more clouds more IR absorption atmosphere warms
Positive feedback enhances runaway warming
Positive feedback enhances runaway warming
Ocean Current
s
Ocean Current
sSurface currents
move warm water toward poles
Surface currents
move warm water toward poles
Gulf Stream warms east coast of US and
Europe
Gulf Stream warms east coast of US and
Europe
Ocean CurrentsOcean CurrentsSea Surface Temperature monitored by
satellites, augmented by buoy array.Sea Surface Temperature monitored by
satellites, augmented by buoy array.
Equator
http://www.ssec.wisc.edu/data/sst.html
9/26/079/26/07
Hurricanes
Winter Temperature PatternsWinter Temperature Patterns Landforms, water, latitude affect temps. Landforms, water, latitude affect temps.
Frozen landscape
pushes isotherms
toward equator
Frozen landscape
pushes isotherms
toward equator
Gulf Stream pushes
isotherms toward arctic
Gulf Stream pushes
isotherms toward arctic
Evenly spaced isotherms over uninterrupted
ocean.
Evenly spaced isotherms over uninterrupted
ocean.
Dramatic Temp.
changes at
mountains, shores
Dramatic Temp.
changes at
mountains, shores
Siberia gets as cold as Greenland’s Icesheet!Siberia gets as cold as Greenland’s Icesheet!
Summer Temperature PatternsSummer Temperature Patterns Landforms, water, latitude affect temps. Landforms, water, latitude affect temps.
Warmed landscape
pushes isotherms
toward mountains
Warmed landscape
pushes isotherms
toward mountains
Gulf Stream pushes
isotherms toward arctic
Gulf Stream pushes
isotherms toward arctic
Evenly spaced isotherms over uninterrupted
ocean.
Evenly spaced isotherms over uninterrupted
ocean.
Annual Range of TemperaturesAnnual Range of Temperatures Continental climates most extreme Continental climates most extreme
Siberia varies by 60 C = (108 F)
Siberia varies by 60 C = (108 F)
Temperature of equatorial ocean barely varies.Temperature of equatorial ocean barely varies.
“Summer” and “Winter” don’t make sense everywhere!
“Summer” and “Winter” don’t make sense everywhere!