planetary temperatures
100 1000 10000
Average D istance from Sun (10 6 km )
note logarithm ic scale !
-400
-200
0
200
400
600
Ave
rage
Pla
net
ary
Tem
pera
ture
(°C
)
M ercury
Venus
Earth
M ars
Jup ite r Saturn
U ranus N eptune
eccentricity:the influence of elliptical orbits
http://astroprofspage.com/archives/1024
Note: for the Earth this difference is quite small – about 3%
• changes in the shape of the earth’s orbit
• affects how solarradiation is distributedthroughout the year
http://www.homepage.montana.edu/~geol445/hyperglac/time1/milankov.htm
• axial tilt orobliquity
• determines howmuch sunlight reaches the northern and southern hemispheres during summer / winter
• influences the severity of the seasons
Milankovitch (over) simplified
• changes in orbital parameters change the way solar radiation is distributed across the earth
• it changes the absolute amount of solar radiation a little
(due to Kepler’s second law)
• so why don’t the effects just average out?
Important Greenhouse Gasses
Water vapor H2O 0.1 ppm – 40,000 ppm
Carbon Dioxide CO2 370 ppm
Methane CH4 1.7 ppm
Nitrous Oxide N2O 0.3 ppm
Ozone O3 0.01 ppm (at surface)
Freon – 11 CCl3F 0.00026 ppm
Freon – 12 CCCl2F2 0.0054 ppm
Data from Kump et al., 2004
The Greenhouse Effect
• Atmosphere transparent to visible light
• Atmosphere opaque to long wavelength radiation (infrared)
1600 1700 1800 1900 2000
Year
1363
1364
1365
1366
1367
mea
n a
nnua
l sol
ar ir
radi
ance
(W
/ m
2 )
data from :Lean, J.. 2004. Solar Irradiance Reconstruction.IG BP PAG ES/W orld Data Center for Paleoclim atology Data Contribution Series # 2004-035.NO AA/NG DC Paleoclim atology Program , Boulder CO , USA.
total solar irradiance 1610 - 2000
The Reverend Robert WalkerSkating on Duddingston Loch
attributed to Henry Raeburn, 1790's
Pieter Brueghel the Younger. Winter Landscape, 1621
little ice age
London Bridge Frost Fair Luke Clenell, 1814
Top Related