12.842 Climate Physics and
Chemistry
Fall 2006
Ed Boyle, Kerry Emanuel, Carl Wunsch
Ocean & Atmospheric Chemistry Lectures
Sept. 29, Oct. 2, 4, 11, 13, 16, 18, 20
Paleoclimate Lectures
Sept. 8, 11, 13, 18, 20, 22, 25, 27
The Origin of the
Earth, the
Atmosphere & Life
Outline
Time T(K) E Density What’s Happening?
The standard
cosmological
model of the
formation of the
universe:
“The Big Bang”
Table removed due to
copyright restrictions.
• From Steven Weinberg, The First
Three Minutes
•Also see:
http://superstringtheory.com/cosmo/cosmo3.html
for a terrific tour of the Big Bang!
Outline pt I.
Evidence for
the Big Bang
#1: An
Expanding
Universe
•The galaxies we see in all directions are moving away from the
Earth, as evidenced by their red shifts.
•The fact that we see all stars moving away from us does not imply
that we are the center of the universe!
•All stars will see all other stars moving away from them in an
expanding universe.
•A rising loaf of raisin bread is a good visual model: each raisin
will see all other raisins moving away from it as the loaf expands.
http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html & http://map.gsfc.nasa.gov/m_uni/uni_101bbtest1.html &
http://en.wikipedia.org/wiki/Metric_expansion_of_space
Image removed due to
copyright restrictions.
Evidence for the
Big Bang #2:
The 3K Cosmic
Microwave
Background
•Uniform background radiation in the microwave region of the spectrum is
observed in all directions in the sky.
•Has the wavelength dependence of a Blackbody radiator at ~3K.
•Considered to be the remnant of the radiation emitted at the time the
expanding universe became transparent (to radiation) at ~3000 K. (Above
that T matter exists as a plasma (ionized atoms) & is opaque to most
radiation.)
Image courtesy of NASA.
The Cosmic Microwave Background in Exquisite
Detail: Results from the Microwave Anisotropy
Probe (MAP)-Feb. 2003
•Age of universe: 13.7 +/- 0.14 Ga
Results from the Cosmic Microwave Anisotropy Probe (CMAP), Seife (2003) Sc