Global Warming is Limited by Carbon Availability • presenter: Brian Davies, Physics Dept, WIU • For a summary of this presentation with pointers to internet resources, see my webpage: http://frontpage.wiu.edu/~bmd111/carbon.htm • The key analytical work presented here is that of Prof. David Rutledge, Chair of the Division of Engineering and Applied Science at the California Institute of Technology. See http://rutledge.caltech.edu/ for a video and slide presentation. • James Hansen and others are also working on updating their assumptions about carbon availability. • Conclusion: many of the scenarios in the IPCC study assume that carbon emission is much higher than possible from known reserves. Atmospheric CO2 has been steadily increasing during the Anthropocene epoch (NOAA data) From the Carbon Dioxide Information Analysis Center http://cdiac.ornl.gov/trends/co2/graphics/mlo145e_thrudc04.pdf The trend continues upward, and can be estimated by calculations, using as an input an estimate of the emission of carbon dioxide by human activity. The primary source from human activity is the combustion of fossil fuels such as coal, petroleum and its derivative products, and natural gas. Where does this line trend in the future? How much carbon is available to be burned and how much will end up in the atmosphere? Reference: http://www.esrl.noaa.gov/gmd/ccgg/trends/ A goal of the calculations is to estimate this trend from basic physics. The American Geophysical Union has released a statement on “Human Impacts on Climate” which states that “The Earth's climate is now clearly out of balance and is warming. Many components of the climate system—including the temperatures of the atmosphere, land and ocean, the extent of sea ice and mountain glaciers, the sea level, the distribution of precipitation, and the length of seasons—are now changing at rates and in patterns that are not natural and are best explained by the increased atmospheric abundances of greenhouse gases and aerosols generated by human activity during the 20th century. ... If this 2°C warming is to be avoided, then our net annual emissions of CO2 must be reduced by more than 50 percent within this century. With such projections, there are many sources of scientific uncertainty, but none are known that could make the impact of climate change inconsequential. …” For the full statement (and it should be read as an entire statement) see: http://www.agu.org/sci_soc/policy/positions/climate_change2008.shtml UN Panel on Climate Change (IPCC) • The UN Intergovernmental Panel on Climate Change (IPCC) publishes assessment reports that reflect the consensus on climate change • The 4th report has been released (www.ipcc.ch) – Over one thousand authors – Over one thousand reviewers • Updated measurements – Temperature rising 0.013C per year (1956-2005) – JPL satellite measurements indicate that sea level rising 3mm per year (1993-2003) Cumulative Future Fossil-Fuel Carbon Emissions, Gt. The IPCC report envisions 40 different scenarios with varying assumptions. 2,000 1,000 0 2000 2050 2100 Adapted from: http://rutledge.caltech.edu One of my major points in this talk: We need to estimate the actual amount of carbon emissions that could be emitted by burning known amounts of hydrocarbons, and not just make simple assumptions about growth rates. Annual Crude-Oil Production, billions of barrels. Historical U.S. petroleum production 1970 Hubbert’s Peak Alaskan oil 3 2 1 0 1900 • • 1920 1940 1960 1980 2000 Data from the DOE’s Energy Information Administration (EIA) From http://rutledge.caltech.edu Cumulative Production, billions of barrels. US Crude-Oil Production – cumulative plot 200 29Gb remaining 100 0 1900 • • • 1950 2000 2050 2100 EIA data (1859-2006), and graph by Rutledge Cumulative production assumes an ultimate of 225Gb production Hubbert’s larger ultimate was 200 billion barrels (the Alaska trend is 19 billion barrels) Growth-Rate Plot for US Crude Oil Growth Rate for Cumulative . 10% Trend line is for normal fit (225 billion barrels) 5% 0% 0 100 200 Cumulative Production, billions of barrels • • EIA data (cumulative from 1859, open symbols 1900-1930, closed symbols 1931-2006) This plot shows annual production divided by cumulative production (vertical axis) vs. cumulative production (horizontal axis) (also known as Hubbert linearization) Now consider world oil production • This method (known as Hubbert Linearization in some discussions) allows for an estimate of ultimate production (the total amount of the resource that will eventually be extracted from the ground). • We will show the global oil production curves, then • skip the display of world oil production and go on to • estimate the ultimate quantity of all types of hydrocarbon that will be extracted (Oil, natural gas, and natural gas liquids, etc., but not liquids derived from biomass). Consumption has overtaken discovery, with a 40 year lag in peaks. From a talk by Albert Bartlett, U. Colorado (retired). The projections in this graph are outdated, so just look at the historical data. Growth Rate for Cumulative . Growth-Rate Plot for World Hydrocarbons (from Rutledge) 6% 4% Trend line for 3Tboe remaining 2% 0% 0 1 2 3 Cumulative Production, trillion barrels of oil equivalent • • • Oil + natural gas + natural gas liquids like propane and butane Data 1965, 1972, 1981, 2006 BP Statistical Review (open 1960-1982, closed 1983-2005) The German resources agency BGR gives hydrocarbon reserves as 2.7Tboe – – Expectation of future discoveries and future OPEC oil reserve reductions Includes 500Gboe for non-conventional sources like Canadian oil sands Cumulative Production,Tboe. World Hydrocarbon Production (from Rutledge) 4 3 2 3Tboe remaining 1 0 1960 1980 2000 2020 2040 2060 2080 2100 • Cumulative normal (ultimate production 4.6Tboe) • IPCC scenarios assume that 11 to 15Tboe is available Coal production • • • • • • • • Coal resources – ALL the coal underground (a huge resource) Coal reserves – Coal that can be economically mined (much less) New data on coal usually results in downgrading of the proven reserves. German hard coal reserves were downgraded by 99 percent from 23 billion tons to 0.183 billion tons in 2004. German lignite reserves have been downgraded drastically, which is noteworthy because Germany is the largest lignite producer world-wide. Poland downgraded its hard coal reserves by 50 percent compared to 1997. Poland downgraded its lignite and subbituminous coal reserves in two steps since 1997 to zero. Some of the IPCC scenarios assumed up to 18 TBoe of coal would be mined and burned on a global basis, and we will see that estimates of actually-recoverable coal reserves may be around 1.6 TBoe, much lower than assumed by the IPCC authors. (Even generous estimates of coal production yield a figure of 3.5 TBoe.) British Coal Production (from Rutledge) Annual Production, Mt . 300 200 100 0 1850 • • 1900 1950 2000 Data from the US National Bureau of Economic Research (1854-1876), the Durham Coal Mining Museum (1877-1956), and the British Department of Trade and Industry (1957-2006) In the peak production year, 1913, there were 3,024 mines Cumulative Production, Gt. Cumulative British Coal Production (from Rutledge) Pre-war fit 20 Post-war fit 10 0 1850 • • 1900 1950 2000 Pre-war lms fit (1854-1945, ultimate 25.6Gt, mean 1920, sd 41 years) Post-war lms fit (1946-2006, ultimate 27.2Gt, mean 1927, sd 39 years) Growth Rate for Cumulative . Growth-Rate Plot for British Coal (from Rutledge) 4% 2% 0% 0 5 10 15 20 25 Cumulative Production, Gt • • 1854-2006, 1853 cumulative from William Jevons, The Coal Question Already near the trend line in 1854 Reserves vs Trends for Remaining Production Region Reserves Gt Trends Gt North America 255 135 East Asia 190 70 Australia and New Zealand 79 50 Europe 55 23 Africa 30 10 223 18 Former Soviet Union • South Asia 111 Central and South America 20 World (at 3.6boe/t) 963 (3.5Tboe) 437 (1.6Tboe) North America includes trends for the East (40Gt), the West (25Gt), reserves for Montana (68Gt), and trends for Canada and Mexico (2Gt) • IPCC scenarios assume 18Tboe is available for production Cumulative Production, Tboe. Future Fossil-Fuels Production (from Rutledge) 4 3 2 1 0 1960 • • • • 3.0Tboe hydrocarbons remaining 1.6Tboe coal remaining 1980 2000 2020 2040 2060 2080 2100 Hydrocarbons cumulative normal (ultimate 4.6Tboe, lms fit for mean 2018, sd 35 years) 2005 coal cumulative from the 2005 BGR Energy Resources Report (USGS for US) Coal cumulative normal (ultimate 2.6Tboe, lms fit for mean 2024, sd 48 years) The standard deviations of 35 and 48 years can be compared to time constants for temperature and sea level Fossil-Fuel Carbon Emissions (from Rutledge) Cumulative Carbon Emissions, Gt. 800 600 • Super-Kyoto Profile 400 520Gt remaining 200 0 1960 • • Producer-Limited Profile 1980 2000 2020 2040 2060 2080 2100 Total fossil-fuel carbon is an input for climate-change models Carbon coefficients from the EIA: oil (110kg/boe), gas (79kg/boe), coal (141kg/boe), and future hydrocarbons weighted by BGR reserves (98kg/boe) The Super-Kyoto Profile is a 50% stretch-out in time with the same ultimate production Cumulative Future Fossil-Fuel Carbon Emissions, Gt. From the work by Rutledge, the main point of this talk comes in comparing with the IPCC Scenarios: • • 2,000 1,000 Producer-Limited Profile 0 2000 2050 2100 The Producer-Limited profile has lower emissions than any of the 40 IPCC scenarios, which puts limits on the eventual temperature rise! Jean Laherrere was the first to point out this anomalous situation Conclusion: The Producer-Limited profile has lower emissions than any of the 40 IPCC scenarios. This means that these scenarios are probably unrealistic. Carbon availability limits the eventual temperature rise; it may be significantly lower than the IPCC estimates. • Rutledge web site with video and accompanying Powerpoint slides: http://rutledge.caltech.edu/ • Dr. Rutledge has also summarized this in a web discussion forum: http://www.theoildrum.com/node/2697 • CalTech has several related video presentations (by Hansen, etc): http://today.caltech.edu/theater/list?subset=science • Ken Deffeyes, Hubbert’s Peak, in the Malpass library • William Catton, Overshoot, in the Malpass library • http://www.architecture2030.org/home.html Concluding Thoughts from Dr. Rutledge • Results – Estimate for future hydrocarbon production (3Tboe) is consistent with reserves – Estimate for future coal production (1.6Tboe) is about half of reserves – The time constants for fossil-fuel exhaustion are of the order of 50 years – The time constants for temperature and sea-level change are of the order of 1,000 years • Implications – Since estimate for future fossil-fuel production is less than all 40 UN IPCC scenarios, producer limitations could provide useful constraints in climate modeling – A transition to renewable sources of energy is likely – To lessen the effects of climate change associated with future fossil-fuel use, reducing ultimate production is more important than slowing it down • Opportunities – One-third of US fossil-fuel reserves are on federal lands, so ultimate production could be reduced substantially by limits on new leases for mining and drilling – The US has an outstanding resource in its direct sunlight from COAL: RESOURCES AND FUTURE PRODUCTION Background paper prepared by the Energy Watch Group March 2007 EWG-Series No 1/2007 updated version: 10th July 2007 US coal-producing regions From a National Academy of Sciences report, June 2007 from COAL: RESOURCES AND FUTURE PRODUCTION Background paper prepared by the Energy Watch Group March 2007 EWG-Series No 1/2007 updated version: 10th July 2007 from COAL: RESOURCES AND FUTURE PRODUCTION Background paper prepared by the Energy Watch Group March 2007 EWG-Series No 1/2007 updated version: 10th July 2007 from COAL: RESOURCES AND FUTURE PRODUCTION Background paper prepared by the Energy Watch Group March 2007 EWG-Series No 1/2007 updated version: 10th July 2007 from COAL: RESOURCES AND FUTURE PRODUCTION Background paper prepared by the Energy Watch Group March 2007 EWG-Series No 1/2007 updated version: 10th July 2007 from COAL: RESOURCES AND FUTURE PRODUCTION Background paper prepared by the Energy Watch Group March 2007 EWG-Series No 1/2007 updated version: 10th July 2007 CO2 levels on geologic time scales were much higher than in the paleolithic period (or now) (present level is about 350 ppm = 0.03%) R. Dudley, J. Exper. Biol.,201, 1043, 1998.