Phanerozoic Atmospheric Carbon Dioxide Concentration Proxy Data ----------------------------------------------------------------------- World Data Center for Paleoclimatology, Boulder and NOAA Paleoclimatology Program ----------------------------------------------------------------------- NOTE: PLEASE CITE ORIGINAL REFERENCE WHEN USING THIS DATA!!!!! NAME OF DATA SET: Phanerozoic Atmospheric Carbon Dioxide Concentration Proxy Data LAST UPDATE: 10/2008 (Original receipt by WDC Paleo) CONTRIBUTOR: Dana L. Royer, Wesleyan University IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2008-100 WDC PALEO CONTRIBUTION SERIES CITATION: Royer, D.L. 2008. Phanerozoic Atmospheric Carbon Dioxide Concentration Proxy Data. IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series # 2008-100. NOAA/NCDC Paleoclimatology Program, Boulder CO, USA. ORIGINAL REFERENCE: Royer, D.L. 2006. CO2-forced climate thresholds during the Phanerozoic. Geochimica et Cosmochimica Acta, Vol. 70, pp. 5665-5675. doi:10.1016/j.gca.2005.11.031 ABSTRACT: The correspondence between atmospheric CO2 concentrations and globally averaged surface temperatures in the recent past suggests that this coupling may be of great antiquity. Here, I compare 490 published proxy records of CO2 spanning the Ordovician to Neogene with records of global cool events to evaluate the strength of CO2-temperature coupling over the Phanerozoic (last 542 my). For periods with sufficient CO2 coverage, all cool events are associated with CO2 levels below 1000 ppm. A CO2 threshold of below ~500 ppm is suggested for the initiation of widespread, continental glaciations, although this threshold was likely higher during the Paleozoic due to a lower solar luminosity at that time. Also, based on data from the Jurassic and Cretaceous, a CO2 threshold of below ~1000 ppm is proposed for the initiation of cool non-glacial conditions. A pervasive, tight correlation between CO2 and temperature is found both at coarse (10 my timescales) and fine resolutions up to the temporal limits of the data set (million-year timescales), indicating that CO2, operating in combination with many other factors such as solar luminosity and paleogeography, has imparted strong control over global temperatures for much of the Phanerozoic. ADDITIONAL REFERENCE: Jansen, E., J. Overpeck, K.R. Briffa, J.-C. Duplessy, F. Joos, V. Masson-Delmotte, D. Olago, B. Otto-Bliesner, W.R. Peltier, S. Rahmstorf, R. Ramesh, D. Raynaud, D. Rind, O. Solomina, R. Villalba and D. Zhang, 2007: Palaeoclimate. In: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. GEOGRAPHIC REGION: Global PERIOD OF RECORD: Phanerozoic Era, 542 Million Years BP - present DESCRIPTION: Compilation of 490 published proxy records of atmospheric carbon dioxide concentration over the Phanerozoic (the last 542 million years). Notes 1. Ekart et al. (1999) data: original sources used when possible; some data from the Permo-Carboniferous have been supplanted by data from Tabor et al. (2004) and Montañez & Tabor (unpublished data). 2. Retallack (2001) and Beerling et al. (2002) data: only used data associated with >4 cuticle fragments (see Royer [2003] for details). 3. Demicco et al. (2003) data: supplants the estimates of Pearson and Palmer (2000). 4. Many individual CO2 estimates are based on multiple measurements of the same material. Consult original literature for details. 5. All dates are calibrated to the timescale of Gradstein et al. (2004). The data have also been plotted in figure 6.1 of Jensen et al. 2007, IPCC AR4 WG1, Chapter 6, Palaeoclimate. SOURCE REFERENCE LIST: Andrews, J.E., Tandon, S.K., and Dennis, P.F. 1995. Concentration of carbon dioxide in the Late Cretaceous atmosphere. Journal of the Geological Society, London, v. 152, p. 1-3. Beerling, D.J. 2002. Low atmospheric CO2 levels during the Permo-Carboniferous glaciation inferred from fossil lycopsids. Proceedings of the National Academy of Sciences, USA, v. 99, p. 12567-12571. Beerling, D.J., Lomax, B.H., Royer, D.L., Upchurch, G.R., and Kump, L.R.. 2002. An atmospheric pCO2 reconstruction across the Cretaceous-Tertiary boundary from leaf megafossils. Proceedings of the National Academy of Sciences, USA, v. 99, p. 7836-7840. Beerling, D.J., and Royer, D.L.. 2002. Fossil plants as indicators of the Phanerozoic global carbon cycle. Annual Review of Earth and Planetary Sciences, v. 30, p. 527-556. Cerling, T.E.. 1991. Carbon dioxide in the atmosphere: Evidence from Cenozoic and Mesozoic paleosols. American Journal of Science, v. 291, p. 377-400. Cerling, T.E.. 1992. Use of carbon isotopes in paleosols as an indicator of the P(CO2) of the paleoatmosphere. Global Biogeochemical Cycles, v. 6, p. 307-314. Cox, J.E., Railsback, L.B., and Gordon, E.A.. 2001. Evidence from Catskill pedogenic carbonates for a rapid large Devonian decrease in atmospheric carbon dioxide concentrations. Northeastern Geology and Environmental Sciences, v. 23, p. 91-102. Demicco, R.V., Lowenstein, T.K., and Hardie, L.A.. 2003. Atmospheric pCO2 since 60 Ma from records of seawater pH, calcium, and primary carbonate mineralogy. Geology, v. 31, p. 793-796. Driese, S.G., Mora, C.I., and Elick, J.M.. 2000. The paleosol record of increasing plant diversity and depth of rooting and changes in atmospheric pCO2 in the Siluro-Devonian. in White, R.D., ed., Phanerozoic Terrestrial Ecosystems. New Haven, The Paleontological Society Special Publication 6, p. 47-61. Ekart, D.D., Cerling, T.E., Montañez, I.P., and Tabor, N.J.. 1999. A 400 million year carbon isotope record of pedogenic carbonate: implications for paleoatmospheric carbon dioxide. American Journal of Science, v. 299, p. 805-827. Fletcher, B.J., Beerling, D.J., Brentnall, S.J., and Royer, D.L.. 2005. Fossil bryophytes as recorders of ancient CO2 levels: Experimental evidence and a Cretaceous case study. Global Biogeochemical Cycles, v. 19, GB3012, doi:10.1029/2005GB002495. Freeman, K.H., and Hayes, J.M.. 1992. Fractionation of carbon isotopes by phytoplankton and estimates of ancient CO2 levels. Global Biogeochemical Cycles, v. 6, p. 185-198. Ghosh, P., Bhattacharya, S.K., and Jani, R.A.. 1995. Palaeoclimate and palaeovegetation in central India during the Upper Cretaceous based on stable isotope composition of the palaeosol carbonates. Palaeogeography, Palaeoclimatology, Palaeoecology, v. 114, p. 285-296. Ghosh, P., Ghosh, P., and Bhattacharya, S.K.. 2001. CO2 levels in the Late Palaeozoic and Mesozoic atmosphere from soil carbonate and organic matter, Satpura basin, Central India. Palaeogeography, Palaeoclimatology, Palaeoecology, v. 170, p. 219-236. Ghosh, P., Bhattacharya, S.K., and Ghosh, P.. 2005. Atmospheric CO2 during the Late Paleozoic and Mesozoic: Estimates from Indian soils, in Ehleringer, J.R., Cerling, T.E., and Dearing, M.D., eds., A History of Atmospheric CO2 and Its Effects on Plants, Animals, and Ecosystems. New York, Springer, p. 8-34. Gradstein, F.M., Ogg, J.G., and Smith, A.G., eds.. 2004. A Geologic Time Scale 2004. Cambridge, Cambridge University Press. Greenwood, D.R., Scarr, M.J., and Christophel, D.C.. 2003. Leaf stomatal frequency in the Australian tropical rainforest tree Neolitsea dealbata (Lauraceae) as a proxy measure of atmospheric pCO2. Palaeogeography, Palaeoclimatology, Palaeoecology, v. 196, p. 375-393. Haworth, M., Hesselbo, S.P., McElwain, J.C., and Robinson, S.A.. 2005. Mid Cretaceous pCO2 based on stomata of the extinct conifer Pseudofrenelopsis. Geology, v. 33, p. 749-752. Koch, P.L., Zachos, J.C., and Gingerich, P.D.. 1992. Correlation between isotope records in marine and continental carbon reservoirs near the Palaeocene/Eocene boundary. Nature, v. 358, p. 319-322. Kürschner, W.M.. 1996. Leaf stomata as biosensors of paleoatmospheric CO2 levels. LPP Contributions Series, v. 5, p. 1-153. Kürschner, W.M., Wagner, F., Dilcher, D.L., and Visscher, H.. 2001. Using fossil leaves for the reconstruction of Cenozoic paleoatmospheric CO2 concentrations, in Gerhard, L.C., Harrison, W.E., and Hanson, B.M., eds., Geological Perspectives of Global Climate Change. APPG Studies in Geology 47, Tulsa, The American Association of Petroleum Geologists, p. 169-189. Lee, Y.I.. 1999. Stable isotopic composition of calcic paleosols of the Early Cretaceous Hasandong Formation, southeastern Korea. Palaeogeography, Palaeoclimatology, Palaeoecology, v. 150, p. 123-133. Lee, Y.I., and Hisada, K.. 1999. Stable isotopic composition of pedogenic carbonates of the Early Cretaceous Shimonoseki Subgroup, western Honshu, Japan. Palaeogeography, Palaeoclimatology, Palaeoecology, v. 153, p. 127-138. McElwain, J.C.. 1998. Do fossil plants signal palaeoatmospheric CO2 concentration in the geological past? Philosophical Transactions of the Royal Society London, v. B353, p. 83-96. McElwain, J.C., Beerling, D.J., and Woodward, F.I.. 1999. Fossil plants and global warming at the Triassic-Jurassic boundary. Science, v. 285, p. 1386-1390. McElwain, J.C., Wade-Murphy, J., and Hesselbo, S.P.. 2005. Changes in carbon dioxide during an oceanic anoxic event linked to intrusion into Gondwana coals. Nature, v. 435, p. 479-482. Muchez, P., Peeters, C., Keppens, E., and Viaene, W.A.. 1993. Stable isotopic composition of paleosols in the Lower Visan of eastern Belgium: evidence of evaporation and soil--gas CO2. Chemical Geology, v. 106, p. 389-396. Mora, C.I., Driese, S.G., and Colarusso, L.A. 1996. Middle and Late Paleozoic atmospheric CO2 levels from soil carbonate and organic matter. Science, v. 271, p. 1105-1107. Nordt, L., Atchley, S., and Dworkin, S.I.. 2002. Paleosol barometer indicates extreme fluctuations in atmospheric CO2 across the Cretaceous-Tertiary boundary. Geology, v. 30, p. 703-706. Nordt, L.. 2003. Terrestrial evidence for two greenhouse events in the latest Cretaceous. GSA Today, v. 13(12), p. 4-9. Pagani, M., Arthur, M.A., and Freeman, K.H.. 1999a. Miocene evolution of atmospheric carbon dioxide. Paleoceanography, v. 14, p. 273-292. Pagani, M., Freeman, K.H., and Arthur, M.A.. 1999b. Late Miocene atmospheric CO2 concentrations and the expansion of C4 grasses. Science, v. 285, p. 876-879. Pagani, M., Zachos, J.C., Freeman, K.H., Tipple, B., and Bohaty, S.. 2005. Marked decline in atmospheric carbon dioxide concentrations during the Paleogene. Science, v. 309, p. 600-603. Pearson, P.N., and Palmer, M.R.. 2000. Atmospheric carbon dioxide concentrations over the past 60 million years. Nature, v. 406, p. 695-699. Platt, N.H.. 1989. Lacustrine carbonates and pedogenesis: sedimentology and origin of palustrine deposits from the Early Cretaceous Rupelo Formation, W. Cameros Basin, N. Spain. Sedimentology, v. 36, p. 665-684. Retallack, G.J.. 2001. A 300-million-year record of atmospheric carbon dioxide from fossil plant cuticles. Nature, v. 411, p. 287-290. Robinson, S.A., Andrews, J.E., Hesselbo, S.P., Radley, J.D., Dennis, P.F., Harding, I.C., and Allen, P.. 2002. Atmospheric pCO2 and depositional environment from stable-isotope geochemistry of calcrete nodules (Barremian, Lower Cretaceous, Wealden Beds, England). Journal of the Geological Society, London, v. 159, p. 215-224. Royer, D.L.. 2003. Estimating latest Cretaceous and Tertiary atmospheric CO2 concentration from stomatal indices. in Wing, S.L., Gingerich, P.D., Schmitz, B., and Thomas, E., eds., Causes and Consequences of Globally Warm Climates in the Early Paleogene. Boulder, Colorado, Geological Society of America Special Paper 369, p. 79-93. Royer, D.L., Wing, S.L., Beerling, D.J., Jolley, D.W., Koch, P.L., Hickey, L.J., and Berner, R.A.. 2001. Paleobotanical evidence for near present-day levels of atmospheric CO2 during part of the Tertiary. Science, v. 292, p. 2310-2313. Sinha, A., and Stott, L.D.. 1994. New atmospheric pCO2 estimates from paleosols during the late Paleocene/ early Eocene global warming interval. Global and Planetary Change, v. 9, p. 297-307. Stott, L.D.. 1992. Higher temperatures and lower oceanic pCO2: A climate enigma at the end of the Paleocene Epoch. Paleoceanography, v. 7, p. 395-404. Suchecky, R.K., Hubert, J.F., and Birney de Wit, C.C.. 1988. Isotopic imprint of climate and hydrogeochemistry on terrestrial strata of the Triassic-Jurassic Hartford and Fundy Rift Basins. Journal of Sedimentary Petrology, v. 58, p. 801-811. Tabor, N.J., Yapp, C.J., and Montañez, I.P.. 2004. Goethite, calcite and organic matter from Permian and Triassic soils: Carbon isotopes and CO2 concentrations. Geochimica et Cosmochimica Acta, v. 68, p. 1503-1517. Tanner, L.H., Hubert, J.F., Coffey, B.P., and McInerney, D.P.. 2001. Stability of atmospheric CO2 levels across the Triassic/Jurassic boundary. Nature, v. 411, p. 675-677. van der Burgh, J., Visscher, H., Dilcher, D.L., and Kürschner, W.M.. 1993. Paleoatmospheric signatures in Neogene fossil leaves. Science, v. 260, p. 1788-1790. Yapp, C.J., and Poths, H.. 1996. Carbon isotopes in continental weathering environments and variations in ancient atmospheric CO2 pressure. Earth and Planetary Science Letters, v. 137, p. 71-82. Yapp, C.J.. 2004. Fe(CO3)OH in goethite from a mid-latitude North American Oxisol: Estimate of atmospheric CO2 concentration in the Early Eocene "climatic optimum". Geochimica et Cosmochimica Acta, v. 68, p. 935-947. DATA: 1. Atmospheric CO2 data from PALEOSOLS (d13C) (n = 138) Reference Age Age Age CO2 CO2low CO2high (Ma) old young (ppm) (ppm) (ppm) Suchecky et al., 1988 198 200 197 3010 208 217 200 3160 1800 5400 216 221 211 4500 3000 6000 Platt, 1989 143 146 140 2100 1600 2600 Cerling, 1991 208 217 200 2500 2000 3000 Cerling, 1992 4 5 2 300 0 1000 8 500 0 1000 14 14 13 500 0 1000 53 56 50 300 0 1000 106 112 100 2250 1500 3000 Koch et al., 1992 56 56 55 200 0 350 56 57 56 200 0 350 Muchez et al., 1993 343 345 340 1310 690 1890 Sinha & Stott, 1994 56 56 55 500 300 700 56 57 56 500 300 700 Andrews et al., 1995 68 71 66 300 0 1300 Mora et al., 1996 285 299 271 175 150 200 303 307 299 625 450 800 322 326 318 725 600 1000 322 326 318 525 450 600 322 326 318 800 600 1000 336 345 326 475 450 500 365 375 359 988 700 1275 367 375 359 1500 950 2050 419 421 416 4200 3200 5200 Yapp & Poths, 1996 5 350 280 420 83 100 66 1400 0 3325 163 165 161 350 0 1750 163 165 161 350 0 1750 174 176 172 6300 4700 7900 188 200 176 6300 4700 7900 367 375 359 350 0 1750 447 450 444 5600 4900 6213 Ekart et al., 1999 3 1170 500 2000 5 810 410 1210 6 730 330 1130 7 370 0 970 9 510 110 910 10 1120 720 1520 10 1170 770 1570 13 740 440 1040 13 440 140 740 14 0 0 100 21 780 380 1180 25 1470 770 2200 45 1950 1600 2200 65 0 0 210 66 71 66 820 520 1120 67 71 66 430 130 730 67 71 66 630 330 930 75 84 71 2950 2340 3540 80 84 71 1260 660 1860 115 125 112 2260 1350 3300 115 125 112 2710 1350 3300 115 125 112 2690 1350 3300 120 125 112 1480 1200 1800 153 156 151 3180 2280 3480 191 197 185 4560 3960 5160 174 176 172 1920 1320 2520 216 228 204 1650 900 3450 216 228 204 1830 900 3450 222 228 217 2850 900 3450 241 245 237 710 400 1000 241 245 237 610 300 900 260 261 260 1000 600 1500 294 0 0 300 303 307 299 1470 850 2050 303 307 299 1520 900 2100 343 346 339 2060 1500 2550 391 398 385 1560 960 2160 Lee, 1999 133 136 130 2300 2200 2400 Lee & Hisada, 1999 112 125 100 2450 1700 3200 Driese et al., 2000 368 375 359 2850 2100 3600 370 375 359 3150 2400 3900 402 407 398 3300 2400 4200 417 419 416 3600 2700 4500 Cox et al., 2001 380 385 375 2800 2300 3200 389 392 385 3900 2900 5200 Royer et al., 2001 53 54 53 2034 1434 2634 54 54 54 577 177 977 55 56 55 1152 652 1652 56 56 55 1217 727 1717 56 56 56 1448 948 1948 57 57 56 2041 1441 2641 57 57 57 1185 685 1685 Tanner et al., 2001 198 200 197 2480 1490 3470 216 228 204 2250 1350 3150 Robinson et al., 2002 129 130 128 560 244 895 Nordt et al., 2002 64.3 1000 800 1200 64.8 850 700 1000 65.5 750 600 900 66.0 1400 1100 1700 67.0 750 600 900 77.0 1200 900 1500 Nordt et al., 2003 64.2 534 445 623 64.2 488 407 570 64.4 264 220 308 64.6 334 278 389 64.8 533 444 621 64.9 161 134 188 65.1 549 458 641 65.2 832 693 971 65.4 271 226 316 65.5 0 0 0 65.5 127 106 149 65.6 45 37 52 65.6 790 658 922 65.7 1358 1132 1585 65.9 1277 1064 1490 65.9 796 664 929 66.0 657 548 767 66.0 385 321 449 67.5 31 26 37 67.7 512 427 597 67.8 329 274 384 68.0 475 396 554 68.1 415 346 484 68.3 607 506 708 68.4 435 363 508 68.5 1034 861 1206 68.7 611 509 713 68.9 927 773 1082 69.0 1126 939 1314 69.1 986 822 1150 69.2 365 304 426 69.3 115 95 134 69.5 378 315 441 70.4 763 636 890 70.5 868 723 1012 70.6 883 736 1030 Tabor et al., 2004 283 300 300 3300 270 300 300 2100 Yapp, 2004 52 53 50 2700 2100 3300 Ghosh et al., 2005 (and 1995, 68 71 66 1480 1110 1850 173 200 146 2225 1675 2775 222 228 217 1170 880 1460 237 245 228 1210 910 1510 285 295 276 715 540 890 2. Atmospheric CO2 data from PHYTOPLANKTON/(FORAMS) (d13C) (n = 184) Reference Age CO2 CO2low CO2high (Ma) (ppm) (ppm) (ppm) Freeman & Hayes, 1992 1 430 360 510 8 340 285 400 11 510 425 575 13 420 375 500 20 460 390 540 40 670 570 780 91 860 750 975 94 1005 800 1200 134 1085 940 1225 154 975 650 1350 Stott, 1992 56 500 450 550 56 600 550 740 Pagani et al., 2005 (and 1999a, 5.4 261 240 331 5.8 239 221 303 6.1 249 229 315 6.4 252 233 319 6.8 278 256 356 7.2 242 223 306 7.3 264 243 334 7.6 230 212 292 8.3 237 218 301 8.7 247 228 313 9.1 227 209 287 9.1 268 247 342 9.6 258 238 327 9.6 263 243 334 9.6 234 216 296 9.6 205 188 259 9.8 247 227 312 9.9 235 217 296 10.1 245 226 310 10.2 255 235 323 10.2 244 225 309 10.3 243 225 307 10.5 251 231 318 10.6 223 206 280 10.7 246 227 311 10.9 228 210 287 10.9 238 220 300 11.1 220 203 277 11.3 232 214 293 11.4 211 194 266 11.5 204 188 255 11.6 225 207 284 11.9 245 226 310 12.1 213 196 268 12.2 202 186 254 12.2 208 191 261 12.3 213 196 269 12.5 218 200 277 12.7 210 193 264 12.7 203 186 255 12.8 224 206 283 12.9 211 194 265 12.9 228 210 287 13.1 205 189 258 13.2 225 208 283 13.3 230 212 291 13.3 229 211 288 13.4 220 203 277 13.4 223 206 280 13.5 223 206 280 13.5 203 187 254 13.6 189 173 237 13.7 213 196 269 14.1 231 213 292 14.2 220 202 278 14.5 205 189 257 14.9 236 217 298 15.0 229 212 289 15.1 220 202 277 15.1 215 198 272 15.2 187 172 235 15.3 199 184 250 15.4 202 186 253 15.5 205 190 257 16.1 213 196 268 16.2 176 162 220 16.3 179 165 223 16.3 238 220 301 16.4 201 184 253 16.6 220 202 278 16.8 227 208 318 17.3 232 214 293 17.3 202 185 282 17.3 200 182 279 17.4 216 198 305 17.4 210 192 294 17.5 223 204 314 17.5 231 213 323 17.6 222 204 281 17.6 211 193 296 17.6 207 189 289 17.7 213 195 297 17.7 212 195 296 17.8 215 197 299 17.8 227 209 317 17.8 214 196 300 17.8 197 181 275 17.9 211 194 294 17.9 215 198 299 18.1 228 210 287 18.3 252 232 318 18.3 215 198 301 18.4 216 198 301 18.5 215 198 271 18.6 232 214 294 18.6 216 199 272 18.7 219 200 306 19.1 230 211 291 19.2 218 200 275 19.2 230 211 322 19.2 224 206 312 19.4 209 192 291 19.5 206 188 288 19.7 250 229 353 20.0 294 269 419 20.0 248 228 315 20.2 208 191 263 20.3 343 316 489 20.4 308 283 441 20.5 272 250 383 20.5 208 191 262 20.8 205 189 259 20.8 301 276 428 20.8 202 186 254 20.8 278 255 393 20.9 240 220 305 21.1 261 240 335 21.5 305 280 435 22.2 250 230 353 23.3 211 193 267 23.5 243 222 344 23.8 257 236 328 23.9 242 222 341 23.9 287 263 410 23.9 271 250 343 24.2 256 237 324 24.4 246 226 314 24.5 222 204 282 24.6 248 227 352 24.7 392 361 570 24.7 466 407 671 24.7 749 634 1106 24.9 331 305 428 25.0 343 317 443 25.0 294 270 377 25.1 602 518 852 25.2 351 312 495 25.3 359 318 507 26.1 420 369 624 26.1 419 369 578 26.1 386 339 560 26.6 367 324 510 27.1 582 499 847 27.4 535 462 772 28.6 434 381 619 28.7 383 336 544 28.9 504 438 740 29.5 321 284 451 30.0 457 401 714 30.1 367 325 529 30.2 529 462 752 30.2 570 496 826 30.3 463 401 665 30.6 543 474 787 32.2 1158 962 1678 32.9 864 729 1253 33.0 1326 1068 1992 33.0 832 698 1189 33.0 809 681 1152 33.1 1232 1019 1795 34.1 1093 917 1568 34.4 901 769 1268 34.8 902 769 1270 35.2 709 617 977 35.5 786 673 1101 37.0 1321 1084 1941 37.8 968 825 1365 38.0 768 658 1074 39.7 996 845 1413 39.9 1480 1202 2215 41.1 1041 873 1496 44.0 1176 987 1691 3. Atmospheric CO2 data from STOMATAL INDICES/RATIOS (n = 129) Reference Age Age Age CO2 CO2low CO2high (Ma) old young (ppm) (ppm) (ppm) Van der Burgh et al., 1 2.0 2.1 1.8 358 340 375 & Kürschner et al. 2.7 276 260 292 3.4 358 340 375 4.0 363 345 380 4.6 270 255 285 5.1 358 340 375 7.2 270 255 285 8.5 350 340 360 10.5 370 350 390 McElwain, 1998 43 49 37 619 480 757 168 176 161 677 594 760 297 300 295 300 250 350 313 313 312 247 209 284 402 407 398 1980 1728 2232 McElwain et al., 1999 197 199 196 900 199 200 195 2250 200 201 200 1050 Beerling & Royer, 2002 135 140 130 965 534 1601 168 176 161 597 330 990 172 176 168 1263 698 2094 188 200 176 490 271 813 Kürschner et al., 2001 45 49 40 488 460 515 Retallack, 2001 34 36 32 521 298 1121 35 40 30 920 521 1519 50 55 45 1994 984 3453 64 65 63 1519 859 2430 128 130 125 1350 802 2098 135 140 130 1794 1271 2430 143 146 140 3178 2667 3739 151 156 146 859 560 1271 203 204 200 1194 310 3453 203 204 200 1994 1433 2667 215 217 204 2547 1271 4350 221 228 217 1121 298 3453 223 228 217 1350 521 2790 226 228 217 1051 521 1893 227 228 217 920 302 3046 227 228 217 1433 352 3887 228 228 217 2098 1051 3594 228 228 217 1519 485 3453 228 228 217 747 321 1350 228 228 217 485 310 1794 228 228 217 2790 1794 4038 233 237 228 1699 747 3178 247 250 244 3314 2206 4674 249 251 247 3314 2317 4511 260 267 260 1519 802 2547 260 267 260 1794 1051 2790 261 267 260 920 352 2098 256 258 254 2317 1271 3739 262 267 260 1433 602 2790 263 267 260 1607 521 3594 264 267 260 920 352 2098 265 267 260 2098 1121 3453 297 299 295 452 302 1051 Royer et al., 2001 15.2 16.7 13.7 310 307 313 15.3 16.8 13.8 316 313 318 15.3 16.8 13.8 316 313 318 16.5 18.0 15.0 396 385 413 54.0 54.1 53.9 342 339 346 54.1 54.2 54.0 323 321 326 54.5 54.6 54.4 345 339 352 55.4 55.5 55.3 360 353 369 55.7 55.8 55.6 373 368 381 55.8 58.8 52.8 826 661 1000 55.9 56.0 55.8 298 296 300 55.9 56.0 55.8 303 302 304 55.9 56.0 55.8 300 297 302 55.9 56.0 55.8 390 380 406 56.0 56.1 55.8 299 297 301 56.2 56.3 56.1 306 304 308 56.3 56.4 56.1 309 307 311 56.4 56.6 56.3 317 315 318 56.5 56.7 56.4 307 305 308 56.5 56.7 56.4 314 312 316 56.5 56.8 56.3 312 309 314 57.0 57.3 56.6 363 354 376 57.9 58.4 57.3 353 347 361 59.1 59.8 58.5 451 421 519 59.1 59.8 58.5 409 388 447 Beerling, 2002 267 271 267 343 310 376 267 271 267 266 237 295 268 271 267 290 259 321 270 271 267 326 294 358 271 271 267 342 309 375 311 314 307 348 316 380 311 314 307 351 319 383 311 314 307 336 305 367 311 314 307 308 277 339 311 314 307 350 318 382 311 314 307 366 333 399 311 314 307 368 336 400 311 314 307 358 326 390 311 314 307 303 272 334 311 314 307 367 333 401 311 314 307 350 316 384 311 314 307 401 367 435 311 314 307 287 254 320 311 314 307 311 278 344 311 314 307 284 253 315 311 314 307 325 294 356 320 326 314 385 351 419 320 326 314 392 359 425 320 326 314 359 327 391 Beerling et al., 2002 64.5 65.5 63.6 341 337 346 64.6 64.8 64.4 329 325 334 65.0 65.3 64.7 344 340 348 65.0 65.3 64.7 339 334 345 66.0 66.5 65.5 385 379 394 Royer, 2003 54.1 54.2 54.0 370 350 390 61.5 313 310 315 Greenwood et al., 2003 43 49 37 337 325 349 52 56 49 349 337 361 Roth et al., 2003 (modi 409 411 407 2836 2505 4561 McElwain et al., 2005 183 1050 800 1300 183 1550 1200 1900 183 550 400 700 183 950 700 1200 183 950 700 1200 183 600 500 700 Haworth et al., 2005 101 710 580 1420 108 710 603 1400 114 700 597 1340 117 695 590 1380 123 630 530 1220 126 630 530 1250 129 550 450 1130 131 620 590 1270 135 650 500 1300 4. Atmospheric CO2 data from MARINE BORON (d11B) (n = 35) Reference Age CO2 CO2low CO2high (Ma) (ppm) (ppm) (ppm) Demicco et al., 2 0.1 317 252 399 1.0 286 255 321 1.5 271 215 341 3.0 184 146 232 3.3 220 196 247 3.9 251 224 282 6.0 234 208 262 6.2 268 213 337 9.0 179 159 201 10.4 193 172 216 11.4 182 144 229 11.8 208 165 262 13.1 170 135 214 14.7 101 80 127 15.0 126 112 142 16.2 216 172 272 16.7 179 142 225 18.4 160 142 179 19.9 157 125 198 21.7 158 126 201 23.0 210 187 240 23.5 297 265 343 40.1 253 167 767 42.5 71 52 197 44.3 122 108 273 45.7 250 141 890 46.1 788 702 1768 47.0 98 74 262 50.3 189 169 425 51.0 130 92 367 52.2 1285 909 3629 53.2 506 319 1604 55.8 939 593 2977 57.1 703 395 2501 59.9 1189 842 3359 5. Atmospheric CO2 data from LIVERWORTS (d13C) (n = 4) Reference Age Age Age CO2 CO2low CO2high (Ma) old young (ppm) (ppm) (ppm) Fletcher et al., 2005 103 106 99.6 1514 1052 1976 103 106 99.6 1382 1018 1746 103 106 99.6 1105 1017 1193 Royer & McElwain, unpublished 197 199 195 650