Friday, May 10, 2013

Prof. Pierrehumbert: Successful Climate Predictions

{edited May 11th am}

The following lecture given by Ray Pierrehumbert (Ph.D., MIT, 1980) 
the Louis Block Professor in Geophysical Sciences at the University of Chicago -
Fellow, American Geophysical Union -
John Simon Guggenheim Fellow (1996/1997) -
Lead author on the IPCC Third Assessment Report -
Co-author of the National Research Council report on abrupt climate change -
Previously he was with the atmospheric science faculties of MIT and Princeton -

You can learn more about Professor Pierrehumbert at his University of Chicago website: 

This lecture is a review of past predictions made by climatologists and how they have faired in light of the passing decades.  

Including some basic notes, mainly for orientation.


Tyndall Lecture: GC43I. Successful Predictions
San Francisco  |   December 3-7th, 2012
Published on Dec 7, 2012  |   AGUvideos







4:20  -   Climate scientists are too busy with all they don't fully know, that they forget to acknowledge all that they do know.

5:00  -  Successful predictions and climate science.

6:15  -  What Arrhenius got right.

7:20  -  What Arrhenius got wrong.

7:45  -  Knut Angstrom predicts CO2 absorption saturated - little effect on climate.

8:30  -  Angstrom was wrong - related to his lab experiments being inadequate to task - Earth's heat lost comes from radiation out to space from the high top of atmosphere were CO2 is not saturated.

9:30  -  Climate theories predict outgoing IR should be depleted in the 15-micron band.

10:30  -  Tales of Paul Hoffman:  Stages in the life-cycle of a scientific theory:
* Formulate and propose it
* Reject it
* Ignore it (when most of the real work gets done)
* Rediscover it
* Accept it

11:30  -  The standard model

13:30  -  The standard model for stellar structure

14:10  -  The Dark Ages of Anthropogenic Global Warming: 1900 - 1958

16:05  -  Hulbert (1931) Phys. Rev. Computed 2xCO2 warming

16:20  -  The world according to QJRMS, 1900-1960
(Quarterly Journal of the World Meteorological Society)

17:00  -  1928 Simpson's memoire on atmospheric  radiation - 
1932 Review of atmospheric radiation

17:45  -  L.F. Richardson's comment on Simpson (1928)

19:05  -  G.S. Callender 1938 "Artificial Production of CO2 and it's Influence on Temperature.

21:30  -  surface energy budget v. top-of-atmosphere radiation balance.

23:00  -  And then the 1960s

23:50  -  Carl Sagan (1962) who correctly inferred that the microwaves emission of Venus could only be accounted for by the hot house effect of a very thick atmosphere.

24:55  -  1959 Bolin and Eriksson predict CO2 increase (before data was available)

26:20  -  1967 Manabe and Wetherald - Thermo Equilibrium of the Atmosphere (1967)
First correct radiative-convective implementation of the Standard Model applied to Earth

27:50  -  Prediction confirmed !

28:40  -  Manabe and Wetherald - 1975 - Effect of Doubling the CO2 on the Climate of a General Circulation Model (GCM).
* General circulation model with idealized geography
* Computes atmospheric humidity dynamically, rather than assuming fixed relative humidity
* Computes vertical and horizontal temperature structure, incorporating convection, radiation and large scale dynamics
* Computes ice/snow albedo feedback

29:40  -  Graph: Predicted latitude-height structure

30:40  -  Serreze et al. 2009 - Predicted Arctic structure confirmed by the data

31:10  -  Predicted vertical amplification in the tropics hasn't yet come up out of the noise level

31:50  -  1988-1989: First predictions of transient warming with coupled Atmosphere-Ocean GCMs

33:10  -  ... And this is precisely the pattern that is emerging from the data

33:35  -  CLIMAP 1981 - Reconstruction of the world ocean temperatures during last glacial maximum conflicted with GCM findings

34:00  -  ... but GCM's predict substantial cooling - Broccoli and Manabe 1987
also Rind and Peteet 1985 find other problems with CLIMAP 1981

34:40  -  Dick Lindzen explains CLIMAP ... corollary: climate very insensitive to CO2

35:20  -  but, then CLIMAP unravels - MARGO reconstruction 2011

35:50  -  This was an example where models were right and Lindzen and CLIMAP was wrong

36:35  -  Speaking of cases were models were right and the so-called observations were wrong.  There's the famous case of Christy and Spencer and the Micro-wave Sounding Unit Satellite data that seemed to be saying that contrary to everything I was saying about atmosphere and surface warming together and everything the Standard Model predicted the surface might be warming but the atmosphere wasn't, it was actually cooling.  So there was something really wrong and it wasn't CO2.

But, this turned out to be wrong, once the errors in their satellite retrieval were corrected - then there was complete compatibility between the surface warming and the warming of the troposphere.  The troposphere was indeed warming along.

37:10  -  Another case of a wrong prediction - water vapor feedback is essential to CO2 being a significant threat - It's the amplification from water-vapor feedback that makes doubling CO2 a big problem.

37:30  -  Lindzen goes after water-vapor feedback in 1990, with a theory that predicted that actual water-vapor feedback would be negative...  meaning atmosphere would get drier with increasing CO2

38:00  -  Many physical experiments showing this not to be the case - with warming atmospheric moisture goes up

38:30  -  Lindzen's science may be wrong science - but it's OK because scientist learn from it

38:50  -  ... But, then there is the stuff that isn't even wrong - because it is so badly formulated it don't even make a prediction that can be falsified.

39:00  -  Courtillot's Earth magnetic field and climate... cosmic-ray/climate connection

39:15  -  Rasool and Schneider 1971: Aerosol cooling will beat CO2 warming...
error found (CO2's influence vastly underestimated), result dismissed by 1975.

40:30  -  The world is warming compatibly with predictions of GHG theory

41:00  -  Failure to predict in advance - 
taking into account the delaying effect of ocean heat uptake

42:10  -  ... one possibility is ocean heat uptake fluctuation, not modeled well.
oceans v aerosols challenge . . .

45:40  -  "I think that the standard model has done pretty well, I think our predictions have held up pretty well.    There's been a constant challenge and testing over the last hundred years of the connection between CarbonDioxide and Climate - so I think we in climate science have earned the right to be listened to...

~ ~ ~
45:55  -  "The Image"  From Planet of the Apes - George Taylor discovers the buried Statue of Liberty and understands he is on Earth and his people destroyed it.  Seems to me a fitting icon for those of us who've been paying attention to the dishonest Republican derailment of the Global Warming "Debate" for the past decades. 
~ ~ ~

45:55  -  ...Though the question is: Is anybody actually listening?  If you make a prediction in the forest and no one is there listening,  have you ever actually made a prediction and has it done any good?

46:10  -  (referring the above mentioned image)  "Will this be our epitaph ?

46:30  -  "We were given fair warming, but we did this to ourselves."

47:15  -  "But, there's another storyline, this one with a happy ending..."

48:50  -  Questions and Answers
~ ~ ~ ~ ~ ~ ~ 


Book by Ray Pierrehumbert and David Archer 

Whiley Press


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