the exam results …. note: ex1 score = (number correct)/49 you get one ‘bonus’ question due to...
TRANSCRIPT
![Page 1: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/1.jpg)
The Exam results ….
Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test
![Page 2: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/2.jpg)
The Earth
How it got this way ….
![Page 3: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/3.jpg)
Accretion of planetesimals
![Page 4: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/4.jpg)
Accretion of planetesimals(4.54 billion years ago)
Massive enough to form a sphere
START
![Page 5: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/5.jpg)
Accretion of planetesimals
Gravitational and impact energies melts it
Temp. and pressure increase inwards to
the core
![Page 6: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/6.jpg)
Differentiation
Denser materials sinkLess-dense ones float
IRON CORE
MANTEL
“Solid” crust
Maybe only 10 million years later
Liquid Fe core + rotation =
magnetic field
![Page 7: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/7.jpg)
Must have looked like this …
![Page 8: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/8.jpg)
After some cooling
IRON CORE
MANTEL
Lithosphere“cool, rigid rock”
![Page 9: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/9.jpg)
Meanwhile: “Heavy bombardment period”
IRON CORE
MANTEL
Comets – ICE (water!)
First few hundred-million years
Asteroids
Asteroids
Still cooling,Heavy crateringand Volcanism
![Page 10: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/10.jpg)
![Page 11: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/11.jpg)
Opps!
IRON CORE
MANTEL
“Theia”
(more than 4.4 billion years ago)
Moon forms from the less-dense
outer layers that get blasted off
![Page 12: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/12.jpg)
![Page 13: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/13.jpg)
After some major recovery …. Late bombardment tapers off
IRON CORE
MANTEL
First oceans form about 3.8 billion years ago from comet water!
![Page 14: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/14.jpg)
Note: close moon
![Page 15: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/15.jpg)
After A LONG time …. The present
IRON CORE
MANTEL
Lithosphere“cool, rigid rock”
Convective cooling by the mantel
driven by temp. difference
100 million year time scale.(bottom to top)
![Page 16: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/16.jpg)
Tectonic plates
![Page 17: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/17.jpg)
Tectonic activity
![Page 18: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/18.jpg)
![Page 19: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/19.jpg)
Our Atmosphere
How it got this way ….
![Page 20: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/20.jpg)
Volcanism!
Gasses trapped within earth’s mantel released
Liquid water!!!
![Page 21: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/21.jpg)
Were did they all go?
Were did this come from?
![Page 22: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/22.jpg)
The light stuff: H2 and He drifted off into space.(Low mass -> high speeds > escape velocity)
Were did they all go?
The semi-light stuff: CH3 and NH3 broken down in the atmosphere by UV radiation. (No ozone layer back then!!)
Water and CO2 ?? We get very lucky…
Greenhouse gasses!
![Page 23: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/23.jpg)
Temperature warm&cool enough for water to condense and rain!
OCEANS!
CO2 the dissolves in the seas and is locked away in carbonate rocks
(e.g. limestone)
![Page 24: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/24.jpg)
Were did The O2 come from?
Modern stromatolites at Shark Bay, Western Australia. Stromatolites are rock structures built up by layers of cyanobacteria, microorganisms that contribute to the addition of O2 to the atmosphere. Their role in oxygen production dates back billions of years and similar structures to the stromatolites at Shark Bay have been found in rocks as old as 3.5 billion years before present.
![Page 25: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/25.jpg)
Our oxygen is “plant” excretion
![Page 26: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/26.jpg)
Atmospheric cycles – delicate balance of everything
![Page 27: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/27.jpg)
“We’re so lucky” slide:
Earth big enough:
Earth-Sun distance just right:
Slower cooling -- Fe core still molten producing a magnetic field protects us from solar ion wind
We formed just far enough so water would condense, but not freeze.We owe the greenhouse effect for this!
Avoided bad greenhouse by locking most H2O and then CO2 in the oceans
Liquid oceans form the right place for early anaerobic life to evolve.At first O2 was a toxic waste product, building up.
O3 layer which shields later, land-based life from UV.Later life evolved to burn O2 as food.
![Page 28: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/28.jpg)
The “Green-house” effect
![Page 29: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/29.jpg)
Why does something (i.e. a planet) change its temperature?
![Page 30: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/30.jpg)
Energy in Energy out
T
IF Energy in Energy out>Temperature increases!
![Page 31: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/31.jpg)
Energy in Energy out
T
IF Energy in Energy out<Temperature decreases!
![Page 32: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/32.jpg)
Energy in Energy out
T
IF Energy in Energy out=Temperature constant!
EQULIBRIUM
![Page 33: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/33.jpg)
After billions of years cooling, the planets are very near equilibrium!
Only cooling very slowly (if at all)
![Page 34: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/34.jpg)
T
A planet at (surface) temperature T
![Page 35: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/35.jpg)
T
Solar radiation:This is ‘mostly’ in the visible range
ENERGY IN
Reflected (Albedo)
Absorbed
Sun
Ligh
t
Depends on surface compositionCloud reflectivity etc.
Self heating:Radioactive decay!
Decreases with time!
![Page 36: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/36.jpg)
T
Thermal radiation:For (modern) planetary temperatures,This is in the infra-red
ENERGY OUT
![Page 37: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/37.jpg)
SURFACE AT TEMPERATURE T
![Page 38: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/38.jpg)
SURFACE AT TEMPERATURE T
No atmosphere:All IR out to space.
![Page 39: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/39.jpg)
SURFACE AT TEMPERATURE T
Non-greenhouse atmosphere:Gasses do NOT absorb in the IRAll IR out to space.
N2 O2
Ar
![Page 40: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/40.jpg)
SURFACE AT TEMPERATURE T
With a greenhouse atmosphere:Gasses do absorb in the IR
Less IR out to space.
CO2
H2O
Absorbed
Re-emitt
ed
![Page 41: The Exam results …. Note: Ex1 score = (number correct)/49 You get one ‘bonus’ question due to boo-boo on a question in the 3PMer’s test](https://reader030.vdocuments.site/reader030/viewer/2022032702/56649f425503460f94c615df/html5/thumbnails/41.jpg)
For systems close to equilibrium, small changes in the energy balance can cause the surface temperature/climate to change
New sources of CO2 -> “run away” greenhouse effect.
(cooling system failure)
Nuclear war/asteroid strike -> “Nuclear winter”.
(heating system failure)
(increased albedo)