Hubbert’s Peak,
The Coal Question,
and Climate Change
David Rutledge, Caltech
web: rutledge.caltech.edu
email: rutledge@caltech.edu
The UN Panel on Climate Change (IPCC)
• Released 4th Assessment Report in 2007
• For climate projections, the IPCC uses
– 19 computer models with a range for temperature sensitivity
for a doubling of the CO2 level of 2.1 to 4.4°C
– Gives a 66% chance [subjective] that the true sensitivity is in
the range from 2.0 to 4.5°C — little better than a coin toss
– Gives a 90% chance [subjective] that the true sensitivity is
above 1.5°C
• For oil, gas, and coal production, the IPCC works with
scenarios — “… 40 SRES [Special Report on Emissions
Scenarios] scenarios together encompass the current
range of uncertainties…”
2
Oil Production in the IPCC Scenarios
• Gb = billions of barrels
• Range for production from 2010 to 2100 is 1,446Gb to 8,278Gb
— still growing in 13 scenarios in 2100
3
Goal is to Reduce these Uncertainties
• Oil, gas, and coal
–
–
–
–
US oil — Hubbert’s peak
British coal — The Coal Question
World coal
World oil and gas
• Climategate
• Climate change
– CO2 concentrations
– Temperature
– Sea level
4
Characterizing Uncertainty
•
•
•
•
Residuals are the differences between data and models
The model with the smallest residuals is used for projections
Uncertainty refers to the inconsistency of the projections
A range giving the upper and lower values is one measure of
uncertainty
• When residuals look like a string of independent random numbers,
or they can be decorrelated, we can use the computer to create
replications, which are effectively alternative histories
• Replications allow us to calculate confidence intervals — a
statement of the form
“The 90% confidence interval is 0.9°C to 1.8°C”
means that there is a 90% chance that the interval includes the
actual temperature
• Limitation in confidence intervals is that they depend on the form
of the models — models can break, and we will see examples
5
King Hubbert
• Geophysicist at
the Shell lab in
Houston, Texas
• In 1956, he
wrote a paper
suggesting the
possibility of a
peak in US oil
production in
1970
6
US Crude-Oil Production
• Gb = billions of barrels
7
Cumulative Production for US Crude Oil
• Top of the scale for the normal gives a projection for the long-term
production — total production, past and future
8
Probit Transform for US Crude Oil
• The probit transform is the inverse of the standard cumulative normal
• The plot is for probit(q/Q), where q is cumulative production, and Q is
the proposed long-term production
• Maximize r2 (coefficient of determination) — gives 0.99990
• A one-parameter fit, 1 second in Excel
9
Historical Long-Term Fits
•
•
•
•
Range from 218Gb to 237Gb since 1948 (8%)
Large circles are government estimates, small circles are non-government
Government median is 433Gb, non-government median is 230Gb
USGS = US Geological Survey, MMS = Mineral Management Service
10
Residuals for US Crude Oil
• Residuals are expressed in the equivalent months of production
— positive residuals show we are ahead of schedule, negative
residuals show we are behind schedule
• Maximum residual from 1901 on is 11 months — 1 month in 2009
• Residuals can be decorrelated to do statistical replications
11
Replications for Historical Projections
• 1000 replications — current 90% confidence interval is 224Gb to 231Gb
• Confidence interval is now small enough that a single new technology, like
hydro-fractured shale and deep-water production could make it wrong
• The USGS/MMS assessment, 385Gb, implies an extraordinary break in the
production history
12
Kenneth Deffeyes on the USGS Assessments
“When USGS workers tried to estimate resources,
they acted, well, like bureaucrats. Whenever a
judgment call was made about choosing a statistical
method, the USGS almost invariably tended to pick
the one that gave the higher estimate.”
Kenneth Deffeyes
Professor of Geology, emeritus,
Princeton University
Deffeyes’ Law of Bureaucratic Resource Estimates
13
British Coal
Photo by
14
John Cornwell
The Coal Question (1865)
Stanley Jevons
15
UK Coal Production
• Mt = millions of metric tons
• Production is now 16 times less than the peak — the last time
the production was this low, Napoleon was alive
• In 1913, Britain exported 31% of its production, now it imports
74% of the coal it burns
16
Cumulative Production and Historical Fits
• Estimates for long-term production have varied in a 11% range
since 1900
• Fit uses a different s-curve, the logistic function
• Linearized through the logit transform r2 = 99.95%
17
Historical Long-term Fits Compared with Reserves
• Reserve numbers are available before long-term fits
• Produced 18% of the 1871 Royal Commission reserves + cumulative
• Criteria were too optimistic ― 1-ft seams, 4,000-ft depth (Deffeyes’ law)
18
Residuals for UK Coal
• Residuals become larger with time
• Do not try to do confidence intervals for coal production
19
American Coal
Photograph by
Christian Abraham
used with permission
20
Pennsylvania Anthracite Production
• Burns without smoke — used for home heating
• Production is now 59 times less than the peak
21
Historical Projections for PA Anthracite
• Reserve numbers are available before long-term fits stabilize
• Produced 42% of 1921 reserves + cumulative
22
Western US Coal Production
• Early production cycle peaked in 1918
• New start after the 1970 Clean-Air Act Extension, which encouraged
the use of low-sulfur coal, and the 1980 Staggers Rail Act, which
deregulated the railroads
23
Coal West of the Mississippi
• Long-term fit is 45Gt (28% of reserves + cumulative)
24
Residuals for Western Coal
• For the current fit, r2 is 0.999990
25
Long-term Fits Compared with Reserves
• Marius Campbell of the USGS did the first reserves in 1913
• Paul Averitt was responsible for the reserves from 1948-1975. He
responded to criticism from mining engineers by tightening reserves
criteria — seams at least 28 inches thick, up to 1,000 feet deep,
within 3/4 mile from a measurement, 50% recovery
• Now 13 times lower than in 1913
26
African Coal
• SASOL = South African Synthetic Oil company
• Coal production increased dramatically during the boycott period
27
Probit Transform for Africa
•
Projection for the ultimate is 18Gt (45% of reserves + cumulative)
28
Residuals for Africa
• Residuals are largest at the boundary between the two trends
29
Chinese Coal
• Serious problems with the reliability of the production data
30
Cumulative Production versus Historical Fits
• For the current fit, r2 is 0.99959
• Long-term production fit is 128Gt (83% of reserves + cumulative)
31
Long-term Fits Compared with Reserves
• Reserves submitted to World Energy Council in 1989 and 1992 differ by 6:1
• Projection for ultimate is 128Gt (83% of reserves + cumulative)
32
Historical Long-Term Fits for World Coal
•
•
•
•
Other regions not shown, but are available on line
12% range from 1995 on
Current long-term fit is 671Gt, 59% of reserves + cumulative
IPCC range for production through 2100 is 355 to 3,500Gt
33
Where Does the IPCC Get Its Coal Numbers?
World Energy Proved recoverable Additional recoverable
Council survey
reserves, Gt
reserves, Gt
1992
1,039
702
1995
1,032
680
1998
984
3,368
2001
984
409
2004
909
449
2007
847
180
• The scenario report SRES (2000) references the 1995 and 1998 surveys
• The IPCC chose to use additional recoverable reserves and they also
chose 1998 (3,368Gt) instead of 1995 (680Gt) (Deffeyes’ Law)
• Additional recoverable reserves are now 19 times smaller than in 1998
• The 4th Assessment report notes the 2004 survey results, and includes
100,000EJ (5,000Gt) as a “possible resource” with no reference
34
World Oil and Gas Production
• 7.33 barrels of oil = 1 metric ton, toe = metric tons of oil equivalent
• Natural gas added as the energy equivalent
35
Historical Long-term Fits for World Oil and Gas
• 1,000 replications — current confidence interval is 544 to 667Gtoe
• Close to BP’s reserves + cumulative production, 596Gtoe
36
Carbon-Dioxide Emissions
• Carbon coefficients for oil, gas, and coal from the IPCC 4th Assessment
• Projection is less than any of the IPCC scenarios (Deffeyes’ Law?)
37
Climategate
The Climategate Material
• 63MB zip file
• 1,037 emails with threads for a few
scientists at the Climate Research Unit
– earliest is March 6, 1996
– latest is Thursday, November 12, 2009 —
• 3,400 files in 101 folders — data, code,
proposals, reviews, spreadsheets
– earliest is March 3, 1993
– latest is November 11, 2009
From Charles Rotter, at Watts Up With That
“On Tuesday November 17th I was at my desk, browsing the web and
moderating at the same time when the now infamous post came in
from user FOIA at 6:25 [pm] PST.
‘We feel that climate science is, in the current situation,
too important to be kept under wraps. We hereby release a
random selection of correspondence, code, and documents.
Hopefully it will give some insight into the science and the
people behind it.
This is a limited time offer, download now:
http://ftp.tomcity.ru/incoming/free/FOI2009.zip’ “
• Rotter quarantined the message, but he downloaded the material
from the Russian web site
• Rotter gave the material to a colleague, Steve Mosher, who studied
it for two days to assure himself that the material was genuine
before beginning to post emails on November 19
Who Done It?
• Tracks are covered by artificial file creation dates and proxy servers
• Last email November 12  first posting November 17
• An FOI (Freedom of Information) request from Steve McIntyre in
Canada was turned down by post on November 13 — McIntyre says
that he received the letter on November 18
• Emails appear to be selected by key words (SRES, Yamal, SST, …) of
interest to skeptics
• The files appear to be selected by content
• No personal material — however, some has no apparent connection to
an FOI request (fund-raising efforts with Shell Oil company, photoshopped image making fun of climate skeptics)
41
Phil Jones — Director of the Climate Research Unit (CRU)
• Leader of effort to develop the
most important world land
temperature series (CRUTEM3)
— the only thermometer series
that goes back to 1850
• Jones has temporarily stepped
down
• The British MET office has
announced a three-year review
of the temperature record
Response to Freedom of Information (FOI) Act
Phil Jones to Michael Mann (February 2005)
“The two MMs [Steve McIntyre and Ross McKittrick] have been
after the CRU station data for years. If they ever hear there is a
Freedom of Information Act now in the UK, I think I'll delete the file
rather than send to anyone…. We also have a data protection act,
which I will hide behind.”
Phil Jones to Michael Mann (September 2008), apparently related
to an FOI request from David Holland (turned down June 2008)
“Can you delete any emails you may have had with Keith re AR4
[the IPCC 4rth Assessment Report]? Keith will do likewise.… Can
you also email Gene and get him to do the same? I don't have his
new email address. We will be getting Caspar to do likewise.”
Editors and Reviewers
Keith Briffa to Ed Cook (June 2003)
“I am really sorry but I have to nag about that review - Confidentially I now
need a hard and if required extensive case for rejecting - to support Dave
Stahle's and really as soon as you can. Please”
Tom Wigley to Michael Mann, Phil Jones and others (January 2005)
“If you think that [Editor Jim] Saiers is in the greenhouse skeptics camp, then,
if we can find documentary evidence of this, we could go through official
AGU [American Geophysical Union] channels to get him ousted.”
From Phil Jones to others (August 2009)
“All of them know the sorts of things to say - about our comment and the
awful original, without any prompting.”
in response to the journal request: “Please list the names of 5 experts who are
knowledgeable in your area and could give an unbiased review of your work. Please
do not list colleagues who are close associates, collaborators, or family members.”
The Temperature Record
Tom Wigley to Phil Jones (November, 2009)
“Land warming since 1980 has been twice the ocean warming -and skeptics might claim that this proves that urban warming is
real and important.”
Tom Wigley to Phil Jones (November, 2009)
“Here are some speculations on correcting SSTs [sea surface
temperatures] to partly explain the 1940s warming blip. If you
look at the attached plot you will see that the land also shows the
1940s blip (as I'm sure you know). So, if we could reduce the
ocean blip by, say, 0.15 degC, then this would be significant for the
global mean – but we'd still have to explain the land blip.”
Phil Jones to Michael Mann (March, 2004)
“Recently rejected two papers (one for JGR and for GRL) from
people saying CRU has it wrong over Siberia. Went to town in both
reviews, hopefully successfully.”
Land and Ocean Temperatures
• Land adjusted from the CRU (CRUTEM3), land raw is a simple average
of annual temperature differences from the GHCN (Global Historical
Climatology Network)
• Ocean adjusted from the UK Hadley Centre (HadSST2), Ocean raw by
subtracting adjustments from Rayner at al., 2006
• 11-year averages, relative to the 1850-1900 average
Temperature Data Problems
• Quality of temperature data is poor
• Likely to be unrecognized problems of measurement
bias and human bias
• I will try to compensate for possible bias by stating the
temperature rise result as a fraction — how close we
are to the peak temperature, compared where we
were over the 1850 to 1900 period?
• Also there are large fluctuations that apparently come
from natural causes — so I will compare the rise
projection to these fluctuations
47
CO2 Levels from Tom Wigley’s MAGICC
•
•
•
Projection includes 1.45Gt/yr land-use carbon emissions (1951-2005 average)
Logarithmic scale — 64% of the way to the top from the 1850-1900 average
Fraction of variance accounted for is 99.9% (but model has many parameters)
48
Temperature
•
•
•
•
Monthly surface temperatures from the UK Hadley Centre, with seasonal
effects removed
1999-2008 average is 0.7°C above the 1850-1900 average
Model is T = T0 + T1 log2(CO2)d where d accounts for thermal delays
Only 63% of variance explained — residuals are large and complex
49
Two Time Constants in Residuals
• The diamonds indicate the autocorrelation of the residuals
• Model assumes that temperature responds in time to carbon
dioxide as it does to the things the model does not cover
50
Comparison with Crowley and Kim (1995)
8.5
8.4
Model (impulse response set
equal to autocorrelation of
8.3
8.2
8.1
1850
1900
1950
• Step response, with vertical scale adjusted to match at 60 years
• Dotted line shows Crowley and Kim’s energy-balance model
• Solid black line shows the general circulation model Crowley and
Kim used for the comparison with the energy-balance model
Temperature Residuals
• The 90% range extends from ±0.3°C
• Residuals are highly correlated
52
Confidence Band for Association
between Temperature and log2(CO2)
• This slope (T1) is not exactly comparable to the IPCC sensitivity, where
aerosols and greenhouse gases like methane and nitrous oxide are
considered separately — but it has been stable for sixty years
• 1,000 replications — current 90% confidence interval is 1.5°C to 2.9°C
53
Confidence Band for the Temperature
• The future rise associated with the increase in CO2 levels is 0.6°C —
comparable to the 0.6°C residual fluctuations
• 53% of the total projected rise appears to have already occurred
• IPCC uses a few selected marker scenarios, and this artificially alters the
uncertainty — no marker scenarios have oil production rising in 2100 54
World Cereal Yield History
•
•
•
•
From FAO, the Food and Agriculture Organization of the United Nations
Cereals include the three most important food crops — rice, wheat, corn
Per-person supply has improved by 25% over this period
At this level, there is no evidence of damage from climate change
55
Satellite Radar Sea-Level Measurements
• TOPEX and Jason radar satellites — University of Colorado data
• Corrected for air pressure with seasonal effects removed
• 1999 to 2008 rise is 29mm
56
Rahmstorf Model for Sea Level
• Model for rise rate is R = 1.5 + 1.7T mm per year
• Fraction of variance accounted for is 97.5%
• Tide gauge data from John Church and Neil White
57
Decadal Sea-Level Rise
• Rise rate associated with temperature is comparable to the background
• The current decadal sea-level rise is 77% of the projected peak rise,
which is comparable to the rise during the 1940’s
• IPCC uses a few selected marker scenarios, and this artificially alters the
uncertainty — no marker scenarios have oil production rising in 2100 58
Long Beach
Subsidence
— 9m!
• Picture taken by Roger
Coar in 1959 — his
dog’s name was King
• With the permission of
the Long Beach
Historical Society
59
Summary
• Analysis through statistical replications gives smaller uncertainties than
the scenarios and computer models the IPCC uses
• Oil, gas, and coal
– US crude-oil production has been following a normal curve since 1901 — the 1995
USGS/2006 MMS assessment is not consistent with history
– The projection for long-term world oil and gas production is consistent with the BP
reserves
– Long-term production estimates for coal from geological reserves are available early,
but they are too high (6 for the UK, 2 for Pennsylvania anthracite)
– The projection for long-term world coal production is 59% of the reserves plus
cumulative production — varies within a 12% band since 1995
• Climate
– 1/2 of the projected temperature rise appears to already occurred
– The current decadal sea-level rise is 3/4 of the projected peak
– For both temperature and sea level, humanity’s part of the future rise appears to be
comparable to the natural changes
60
Thank You
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Sandro Schmidt at the BGR (the German Resources Agency)
Granger Morgan, Melissa Chan, Ed Rubin and Jay Apt at Carnegie-Mellon
Charlie Kennel at the University of California at San Diego
Kevin Bowman and Dimitri Antsos at the Jet Propulsion Laboratory
Lee Freese and John Rutledge at Freese and Nichols, Inc. in Fort Worth, Texas
Kyle Saunders, Euan Mearns, and Dave Summers at The Oil Drum
Andrew Ferguson at the Optimum Population Trust
Tom Crowley at the University of Edinburgh
Tom Wigley at the National Center for Atmospheric Research for MAGICC
Alex Dessler, Andy Dessler, and Jerry North at Texas A&M
Steve Mohr at the University of Newcastle, New South Wales
Steven Schwartz at Brookhaven National Laboratory
Jim Murray at the University of Washington
Many Caltech colleagues, but particularly Bill Bridges, Paul Dimotakis, David
Goodstein, Nadia Lapusta, John Ledyard, Carver Mead, Tapio Schneider, John
Seinfeld, and Tom Tombrello
Special thanks to Sandy Garstang and Shady Peyvan in the Caltech Library,
Tony Diaz in the Caltech Geology Library, and Kent Potter and Dale Yee in the
Caltech Engineering Division for their perseverance and ingenuity in locating
historical coal production and reserves records
61
• Copyright © 2007, revised 2008, 2009, and 2010 by David Rutledge
• Permission is given to copy this work, provided attribution is given,
and provided that the link http://rutledge.caltech.edu/ is included.
• This site has links to the current version of these slides, an Excel
workbook with calculations for the graphs, and streaming video for a
public lecture. A book is in preparation.
62