Articles | Volume 17, issue 6
https://doi.org/10.5194/cp-17-2515-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/cp-17-2515-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
03 Dec 2021
Research article |
| 03 Dec 2021
| 03 Dec 2021
Climate and ecology in the Rocky Mountain interior after the early Eocene Climatic Optimum
Rebekah A. Stein
CORRESPONDING AUTHOR
Department of Earth and Environmental Sciences, University of
Michigan, Ann Arbor, MI 48109, USA
Department of Earth and Planetary Sciences, University of California,
Berkeley, CA 94720, USA
Department of Earth and Environmental Sciences, University of
Michigan, Ann Arbor, MI 48109, USA
Sarah E. Allen
Department of Biology, Penn State Altoona, Altoona, PA 16601, USA
Michael E. Smith
School of Earth and Sustainability, Northern Arizona University,
Flagstaff, AZ 86011, USA
Rebecca M. Dzombak
Department of Earth and Environmental Sciences, University of
Michigan, Ann Arbor, MI 48109, USA
Brian R. Jicha
Department of Geosciences, University of Wisconsin-Madison, Madison,
WI 53706, USA
Related authors
No articles found.
Tiffany Rivera, McKenna Holliday, Brian Jicha, David H. Malone, Michael J. Braunagel, V. Alex Bonilla Franco, Robert F. Biek, W. Ashley Griffith, and David B. Hacker
EGUsphere, https://doi.org/10.5194/egusphere-2024-2899, https://doi.org/10.5194/egusphere-2024-2899, 2024
Short summary
Short summary
The timing of an ancient gravity slide that originated in the Marysvale volcanic field (Utah) is constrained using 40Ar/39Ar dating of pseudotachylyte, a friction-induced glass that is generated during slide movement, and the volcanic tuffs that were displaced by the slide and those that overly the slide mass. Our results suggest that the Sevier gravity slide occurred at 25.25 Ma. The removal of such a large volume of material likely allowed for the eruption of the Antimony Tuff at 25.19 Ma.
Paolo Boncio, Eugenio Auciello, Vincenzo Amato, Pietro Aucelli, Paola Petrosino, Anna C. Tangari, and Brian R. Jicha
Solid Earth, 13, 553–582, https://doi.org/10.5194/se-13-553-2022, https://doi.org/10.5194/se-13-553-2022, 2022
Short summary
Short summary
We studied the Gioia Sannitica normal fault (GF) within the southern Matese fault system (SMF) in southern Apennines (Italy). It is a fault with a long slip history that has experienced recent reactivation or acceleration. Present activity has resulted in late Quaternary fault scarps and Holocene surface faulting. The maximum slip rate is ~ 0.5 mm/yr. Activation of the 11.5 km GF or the entire 30 km SMF can produce up to M 6.2 or M 6.8 earthquakes, respectively.
Fabrizio Marra, Alison Pereira, Brian Jicha, Sebastien Nomade, Italo Biddittu, Fabio Florindo, Giovanni Muttoni, Elizabeth Niespolo, Paul Renne, and Vincent Scao
Clim. Past Discuss., https://doi.org/10.5194/cp-2021-161, https://doi.org/10.5194/cp-2021-161, 2021
Publication in CP not foreseen
Short summary
Short summary
We demonstrate that coarse gravel deposition in the catchment basins of the major rivers of central Italy is a direct proxy of global deglaciation events associated with meltwater pulses. By precise 40Ar/39Ar dating of the sedimentary deposits we show that emplacement of these gravel beds is closely coincident with discrete events of sea-level rise, with peaks of the Ice-rafted debris (IRD) curve, and with particularly mild (warmer) minima of mean summer insolation at 65° N.
Ethan G. Hyland, Katharine W. Huntington, Nathan D. Sheldon, and Tammo Reichgelt
Clim. Past, 14, 1391–1404, https://doi.org/10.5194/cp-14-1391-2018, https://doi.org/10.5194/cp-14-1391-2018, 2018
Short summary
Short summary
Climate equability is a paradox in paleoclimate research, but modeling suggests that strong seasonality should be a feature of greenhouse Earth periods too. Records of temperature from floral assemblages, paleosol geochemistry, clumped isotope thermometry, and downscaled models during the early Eocene show that the mean annual range of temperature was high, and may have increased during warming events. This has implications for predicting future seasonal climate impacts in continental regions.
Related subject area
Subject: Continental Surface Processes | Archive: Terrestrial Archives | Timescale: Cenozoic
Middle Eocene Climatic Optimum (MECO) and its imprint in the continental Escanilla Formation, Spain
Fluvio-deltaic record of increased sediment transport during the Middle Eocene Climatic Optimum (MECO), Southern Pyrenees, Spain
Terrestrial carbon isotope stratigraphy and mammal turnover during post-PETM hyperthermals in the Bighorn Basin, Wyoming, USA
Palaeo-environmental evolution of Central Asia during the Cenozoic: new insights from the continental sedimentary archive of the Valley of Lakes (Mongolia)
Terrestrial responses of low-latitude Asia to the Eocene–Oligocene climate transition revealed by integrated chronostratigraphy
Mammal faunal change in the zone of the Paleogene hyperthermals ETM2 and H2
Pliocene to Pleistocene climate and environmental history of Lake El'gygytgyn, Far East Russian Arctic, based on high-resolution inorganic geochemistry data
A re-evaluation of the palaeoclimatic significance of phosphorus variability in speleothems revealed by high-resolution synchrotron micro XRF mapping
Nikhil Sharma, Jorge E. Spangenberg, Thierry Adatte, Torsten Vennemann, László Kocsis, Jean Vérité, Luis Valero, and Sébastien Castelltort
Clim. Past, 20, 935–949, https://doi.org/10.5194/cp-20-935-2024, https://doi.org/10.5194/cp-20-935-2024, 2024
Short summary
Short summary
The Middle Eocene Climatic Optimum (MECO) is an enigmatic global warming event with scarce terrestrial records. To contribute, this study presents a new comprehensive geochemical record of the MECO in the fluvial Escanilla Formation, Spain. In addition to identifying the regional preservation of the MECO, results demonstrate continental sedimentary successions, as key archives of past climate and stable isotopes, to be a powerful tool in correlating difficult-to-date fluvial successions.
Sabí Peris Cabré, Luis Valero, Jorge E. Spangenberg, Andreu Vinyoles, Jean Verité, Thierry Adatte, Maxime Tremblin, Stephen Watkins, Nikhil Sharma, Miguel Garcés, Cai Puigdefàbregas, and Sébastien Castelltort
Clim. Past, 19, 533–554, https://doi.org/10.5194/cp-19-533-2023, https://doi.org/10.5194/cp-19-533-2023, 2023
Short summary
Short summary
The Middle Eocene Climatic Optimum (MECO) was a global warming event that took place 40 Myr ago and lasted ca. 500 kyr, inducing physical, chemical, and biotic changes on the Earth. We use stable isotopes to identify the MECO in the Eocene deltaic deposits of the Southern Pyrenees. Our findings reveal enhanced deltaic progradation during the MECO, pointing to the important impact of global warming on fluvial sediment transport with implications for the consequences of current climate change.
Sarah J. Widlansky, Ross Secord, Kathryn E. Snell, Amy E. Chew, and William C. Clyde
Clim. Past, 18, 681–712, https://doi.org/10.5194/cp-18-681-2022, https://doi.org/10.5194/cp-18-681-2022, 2022
Short summary
Short summary
New stable isotope records from pedogenic carbonates through the ETM2, H2, and possibly I1 hyperthermals from the Bighorn Basin highlight significant spatial variability in the preservation and magnitude of these global climate events in paleosol records. These data also provide important climate context for the extensive early Eocene mammal fossil record from the southern Bighorn Basin and support previous hypotheses that pulses in mammal turnover corresponded to the ETM2 and H2 hyperthermals.
Andre Baldermann, Oliver Wasser, Elshan Abdullayev, Stefano Bernasconi, Stefan Löhr, Klaus Wemmer, Werner E. Piller, Maxim Rudmin, and Sylvain Richoz
Clim. Past, 17, 1955–1972, https://doi.org/10.5194/cp-17-1955-2021, https://doi.org/10.5194/cp-17-1955-2021, 2021
Short summary
Short summary
We identified the provenance, (post)depositional history, weathering conditions and hydroclimate that formed the detrital and authigenic silicates and soil carbonates of the Valley of Lakes sediments in Central Asia during the Cenozoic (~34 to 21 Ma). Aridification pulses in continental Central Asia coincide with marine glaciation events and are caused by Cenozoic climate forcing and the exhumation of the Tian Shan, Hangay and Altai mountains, which reduced the moisture influx by westerly winds.
Y. X. Li, W. J. Jiao, Z. H. Liu, J. H. Jin, D. H. Wang, Y. X. He, and C. Quan
Clim. Past, 12, 255–272, https://doi.org/10.5194/cp-12-255-2016, https://doi.org/10.5194/cp-12-255-2016, 2016
Short summary
Short summary
An integrated litho-, bio-, cyclo-, and magnetostratigraphy constrains the onset of a depositional environmental change from a lacustrine to a deltaic environment in the Maoming Basin, China, at 33.88 Ma. This coincides with the global cooling during the Eocene-Oligocene transition (EOT) at ~ 33.7–33.9 Ma. This change represents terrestrial responses of low-latitude Asia to the EOT. The greatly refined chronology permits detailed examination of the late Paleogene climate change in southeast Asia.
A. E. Chew
Clim. Past, 11, 1223–1237, https://doi.org/10.5194/cp-11-1223-2015, https://doi.org/10.5194/cp-11-1223-2015, 2015
Short summary
Short summary
This project describes mammal faunal response in the zone of the ETM2 and H2 hyperthermals (rapid global warming events) of the early Paleogene in the south-central Bighorn Basin, WY. The response includes changes in faunal structure and species relative body size. Comparative analysis suggests that environmental moisture and rate of change are important moderators of response.
V. Wennrich, P. S. Minyuk, V. Borkhodoev, A. Francke, B. Ritter, N. R. Nowaczyk, M. A. Sauerbrey, J. Brigham-Grette, and M. Melles
Clim. Past, 10, 1381–1399, https://doi.org/10.5194/cp-10-1381-2014, https://doi.org/10.5194/cp-10-1381-2014, 2014
S. Frisia, A. Borsato, R. N. Drysdale, B. Paul, A. Greig, and M. Cotte
Clim. Past, 8, 2039–2051, https://doi.org/10.5194/cp-8-2039-2012, https://doi.org/10.5194/cp-8-2039-2012, 2012
Cited articles
Allen, S. E.: Fossil palm flowers from the Eocene of the Rocky Mountain region
with affinities to Phoenix L. (Arecaceae: Coryphoideae), Int. J. Plant Sci., 176, 586–596, 2015.
Allen, S. E.: Reconstructing the local vegetation and seasonality of the
Lower Eocene Blue Rim site of southwestern Wyoming using fossil
wood, Int. J. Plant Sci., 17, 689–714, 2017a.
Allen, S. E.: The Uppermost Lower Eocene Blue Rim Flora from the Bridger
Formation of Southwestern Wyoming: Floristic Composition, Paleoclimate, and
Paleoecology, Doctoral Dissertation, University of Florida, 2017b.
Allen, S. E., Stull, G. W., and Manchester, S. R.: Icacinaceae from the Eocene
of western North America, Am. J. Bot., 102, 725–744, 2015.
Anagnostou, E., John, E. H., Edgar, K. M., Foster, G. L., Ridgwell, A.,
Inglis, G. N., Pancost, R. D., Lunt, D. J., and Pearson, P. N.: Changing
atmospheric CO2 concentration was the primary driver of early Cenozoic
climate, Nature, 533, 380–384, 2016.
Arens, N. C., Jahren, A. H., and Amundson, R.: Can C3 plants faithfully
record the carbon isotopic composition of atmospheric carbon
dioxide?, Paleobiology, 26, 137–164, 2000.
Barclay, R. S. and Wing, S. L.: Improving the Ginkgo CO2 barometer:
implications for the early Cenozoic atmosphere, Earth Planet. Sc. Lett., 439, 158–171, 2016.
Beerling, D. J. and Royer, D. L.: Fossil plants as indicators of the
Phanerozoic global carbon cycle, Ann. Rev. Earth Pl. Sc., 30, 527–556, 2002.
Berner, R. A.: Weathering, plants, and the long-term carbon
cycle, Geochim. Cosmochim. Ac., 56, 3225–3231, 1992.
Bernstein, L., Bosch, P., Canziani, O., Chen, Z., Christ, R., and Riahi, K.: IPCC, climate change 2007, synthesis report, 2007.
Bestland, E. A.: Weathering flux and CO2 consumption determined from
paleosol sequences across the Eocene–Oligocene
transition, Palaeogeogr. Palaeocl., 156, 301–326, 2000.
Bijl, P. K., Houben, A. J., Schouten, S., Bohaty, S. M., Sluijs, A.,
Reichart, G. J., Damsté, J. S. S., and Brinkhuis, H.: Transient Middle
Eocene atmospheric CO2 and temperature
variations, Science, 330, 819–821, 2010.
Boutton, T. W.: Stable Carbon Isotope Ratios of Natural Materials: I. Sample
Preparation and Mass Spectrometric, Carbon isotope techniques, 1, 152–155, 1991.
Brand, L. R., Goodwin, H. T., Ambrose, P. D., and Buchheim, H. P.: Taphonomy
of turtles in the middle Eocene Bridger Formation, SW
Wyoming, Palaeogeogr. Palaeocl., 162, 171–189, 2000.
Breedlovestrout, R. L., Evraets, B. J., and Parrish, J. T.: New Paleogene
climate analysis of western Washington using physiognomic characteristics of
fossil leaves, Palaeogeogr. Palaeocl., 392, 22–40, 2013.
Buchheim, H. P., Brand, L. R., and Goodwin, H. T.: Lacustrine to fluvial
floodplain deposition in the Eocene Bridger Formation, Palaeogeogr. Palaeocl., 162, 191–209,
2000.
Cerling, T. E., Solomon, D. K., Quade, J. A. Y., and Bowman, J. R.: On the
isotopic composition of carbon in soil carbon dioxide, Geochim. Cosmochim. Ac., 55, 3403–3405,
1991.
Cerling, T. E.: Use of carbon isotopes in paleosols as an indicator of the
P(CO2) of the paleoatmosphere, Global Biogeochem. Cy., 6, 307–314, 1992.
Chadwick, O. A., Brimhall, G. H., and Hendricks, D. M.: From a black to a gray box – a mass balance interpretation of pedogenesis, Geomorphology, 3, 369–390, 1990.
Cheeseman, J.: Food security in the face of salinity, drought, climate
change, and population growth, in: Halophytes for food security in dry lands, Academic Press, 111–123, 2016.
Chetel, L. M. and Carroll, A. R.: Terminal infill of Eocene Lake Gosiute,
Wyoming, USA, J. Sediment. Res., 80, 492–514, 2010.
Chetel, L. M., Janecke, S. U., Carroll, A. R., Beard, B. L., Johnson, C. M.,
and Singer, B. S.: Paleogeographic reconstruction of the Eocene Idaho River,
North American Cordillera, GSA Bulletin, 123, 71–88, 2011.
Clyde, W. C., Sheldon, N. D., Koch, P. L., Gunnell, G. F., and Bartels, W.
S.: Linking the Wasatchian/Bridgerian boundary to the Cenozoic Global Climate
Optimum: new magnetostratigraphic and isotopic results from South Pass,
Wyoming, Palaeogeogr. Palaeocl., 167, 175–199, 2001.
Coats, S., Smerdon, J. E., Cook, B. I., and Seager, R.: Are simulated
megadroughts in the North American Southwest forced?, J. Clim., 28, 124–142, 2015.
Cotton, J. M., Jeffery, M. L., and Sheldon, N. D.: Climate controls on soil
respired CO2 in the United States: implications for 21st century
chemical weathering rates in temperate and arid ecosystems, Chem. Geol., 358, 37–45, 2013.
Cornwell, W. K., Wright, I. J., Turner, J., Maire, V., Barbour, M. M.,
Cernusak, L. A., Dawson, T., Ellsworth, D., Farquhar, G. D., Griffiths, H.,
and Keitel, C.: Climate and soils together regulate photosynthetic carbon
isotope discrimination within C3 plants worldwide, Glob. Ecol. Biogeogr., 27, 1056–1067,
2018.
Cramwinckel, M. J., Huber, M., Kocken, I. J., Agnini, C., Bijl, P. K.,
Bohaty, S. M., Frieling, J., Goldner, A., Hilgen, F. J., Kip, E. L.,
Peterse, F., and Sluijs, A.: Synchronous tropical and polar temperature
evolution in the Eocene, Nature, 559, 382–386, 2018.
DeCelles, P. G.: Late Jurassic to Eocene evolution of the Cordilleran thrust belt and foreland basin system, western USA, Am. J. Sci., 304, 105–168, 2004.
Deines, P.: Mantle carbon: concentration, mode of occurrence, and isotopic
composition, in: Early Organic Evolution, Springer, Berlin, Heidelberg, 133–146, 1992.
Dickinson, W. R., Klute, M. A., Hayes, M. J., Janecke, S. U., Lundin, E. R.,
McKittrick, M. A., and Olivares, M. D.: Paleogeographic and paleotectonic
setting of Laramide sedimentary basins in the central Rocky Mountain
region, Geol. Soc. Am. Bull., 100, 1023–1039, 1988.
Dickens, G. R.: Down the Rabbit Hole: toward appropriate discussion of methane release from gas hydrate systems during the Paleocene-Eocene thermal maximum and other past hyperthermal events, Clim. Past, 7, 831–846, https://doi.org/10.5194/cp-7-831-2011, 2011.
Dillhoff, R. M., Dillhoff, T. A., Greenwood, D. R., DeVore, M. L., and Pigg,
K. B.: The Eocene Thomas Ranch flora, Allenby Formation, Princeton, British
Columbia, Canada, Botany, 91, 514–529, 2013.
Doebbert, A. C., Carroll, A. R., Mulch, A., Chetel, L. M., and Chamberlain,
C. P.: Geomorphic controls on lacustrine isotopic compositions: evidence from
the Laney Member, Green River Formation, Wyoming, GSA Bull., 122, 236–252, 2010.
Dzombak, R. M., Midttun, Nikolas C., Stein, R. A., and Sheldon, N. D.:
Incorporating lateral variability and extent of paleosols into proxy
uncertainty, Palaeogeogr. Palaeocl., 582, 110641, https://doi.org/10.1016/j.palaeo.2021.110641, 2021.
Ekart, D. D., Cerling, T. E., Montanez, I. P., and Tabor, N. J.: A
400-million-year carbon isotope record of pedogenic carbonate: implications
for paleoatmospheric carbon dioxide, Am. J. Sci., 299, 805–827, 1999.
Emry, R. J.: Mammals of the Bridgerian (middle Eocene) Elderberry Canyon local fauna of eastern Nevada, Geol. Soc. Am. Spec. Paper, 243, 187–210, 1990.
Ennis, D. J., Dunbar, N. W., Campbell, A. R., and Chapin, C. E.: The effects
of K-metasomatism on the mineralogy and geochemistry of silicic ignimbrites
near Socorro, New Mexico, Chem. Geol., 167, 285–312, 2000.
Fletcher, B. J., Brentnall, S. J., Anderson, C. W., Berner, R. A., and
Beerling, D. J.: Atmospheric carbon dioxide linked with Mesozoic and early
Cenozoic climate change, Nat. Geosci., 1, 43–48, 2008.
Foster, G. L., Hull, P., Lunt, D. J., and Zachos, J. C.: Placing our current
“hyperthermal” in the context of rapid climate change in our geological
past, Philoso. T. R. Soc. A, 376, 20170086, https://doi.org/10.1098/rsta.2017.0086, 2018.
Franks, P. J. and Beerling, D. J.: CO2-forced evolution of plant gas
exchange capacity and water-use efficiency over the
Phanerozoic, Geobiology, 7, 227–236, 2009.
Franks, P. J., Royer, D. L., Beerling, D. J., Van de Water, P. K., Cantrill,
D. J., Barbour, M. M., and Berry, J. A.: New constraints on atmospheric
CO2 concentration for the Phanerozoic, Geophys. Res. Lett., 41, 4685–4694, 2014.
Fricke, H. C. and Wing, S. L.: Oxygen isotope and paleobotanical estimates
of temperature and δ18O–latitude gradients over North America
during the early Eocene, Am. J. Sci., 304, 612–635, 2004.
Gallagher, T. M. and Sheldon, N. D.: A new paleothermometer for forest
paleosols and its implications for Cenozoic climate, Geology, 41, 647–650, 2013.
Gingerich, P. D.: Mammalian responses to climate change at the
Paleocene-Eocene boundary: Polecat Bench record in the northern Bighorn
Basin, Wyoming, in: Causes and Consequences of Globally Warm Climates in the Early Paleogene, edited by: Wing, S. L., Gingerich, P. D., Schmitz, B., and Thomas, E., Geol. Soc. Am. Sp. Paper, 369, 463–478, 2003.
Greenwood, D. R. and Wing, S. L.: Eocene continental climates and
latitudinal temperature gradients, Geology, 23, 1044–1048, 1995.
Greenwood, D. R., Scarr, M. J., and Christophel, D. C.: Leaf stomatal
frequency in the Australian tropical rainforest tree Neolitsea dealbata (Lauraceae) as a proxy
measure of atmospheric pCO2, Palaeogeogr. Palaeocl., 196, 375–393, 2003.
Greenwood, D. R., Pigg, K. B., Basinger, J. F., and DeVore, M. L.: A review
of paleobotanical studies of the Early Eocene Okanagan (Okanogan) Highlands
floras of British Columbia, Canada and Washington, USA, Can. J. Earth Sci., 53,
548–564, https://doi.org/10.1139/cjes-2015-0177, 2016.
Grein, M., Konrad, W., Wilde, V., Utescher, T., and Roth-Nebelsick, A.:
Reconstruction of atmospheric CO2 during the early middle Eocene by
application of a gas exchange model to fossil plants from the Messel
Formation, Germany, Palaeogeogr. Palaeocl., 309, 383–391, 2011.
Gulbranson, E. L., Montanez, I. P., and Tabor, N. J.: A proxy for humidity
and floral province from paleosols, J. Geol., 119, 559–573, 2011.
Guiot, J., Wu, H. B., Garreta, V., Hatté, C., and Magny, M.: A few prospective ideas on climate reconstruction: from a statistical single proxy approach towards a multi-proxy and dynamical approach, Clim. Past, 5, 571–583, https://doi.org/10.5194/cp-5-571-2009, 2009.
Gutjahr, M., Ridgwell, A., Sexton, P. F., Anagnostou, E., Pearson, P. N.,
Pälike, H., Morris, R. D., Thomas, E., and Foster, G. L.: Very large
release of mostly volcanic carbon during the Palaeocene–Eocene Thermal
Maximum, Nature, 548, 573–577, 2017.
Hamzeh, M., and Dayanandan, S.: Phylogeny of Populus (Salicaceae) based on
nucleotide sequences of chloroplast TRNT-TRNF region and nuclear
rDNA, Am. J. Bot., 91, 1398–1408, 2004.
Hamzeh, M., Périnet, P., and Dayanandan, S.: Genetic Relationships among
species of Populus (Salicaceae) based on nuclear genomic data, J. Torr. Bot. Soc., 133, 519–527,
2006.
Haynes, S. J., MacLeod, K. G., Ladant, J. B., Guchte, A. V., Rostami, M. A.,
Poulsen, C. J., and Martin, E. E.: Constraining sources and relative flow
rates of bottom waters in the Late Cretaceous Pacific
Ocean, Geology, 48, 509–513, 2020.
Henehan, M. J., Ridgwell, A., Thomas, E., Zhang, S., Alegret, L., Schmidt,
D. N., Rae, J. W., Witts, J. D., Landman, N. H., Green, S. E., and Huber, B.
T.: Rapid ocean acidification and protracted Earth system recovery followed
the end-Cretaceous Chicxulub impact, P. Natl. Acad. Sci., 116, 22500–22504, 2019.
Henehan, M., Edgar, K., Foster, G., Oenman, D., Hull, P., Greenop, R.,
Anagnostou, E., and Pearson, P.: Revisiting the Middle Eocene Climatic
Optimum “Carbon Cycle Conundrum” with new estimates of atmospheric pCO2
from boron isotopes, Paleoceanogr. Paleocl., 35, e2019PA003713, https://doi.org/10.1029/2019PA003713, 2020.
Henry, C. D., Hinz, N. H., Faulds, J. E., Colgan, J. P., John, D. A., Brooks, E. R., and Castor, S. B.: Eocene–Early Miocene paleotopography of the Sierra Nevada–Great Basin–Nevadaplano based on widespread ash-flow tuffs and paleovalleys, Geosphere, 8, 1–27, 2012.
Holdridge, L. R.: Life Zone Ecology, Tropical Science Center, San Jose, Costa Rica,
1–206, 1967.
Huang, C., Retallack, G. J., Wang, C., and Huang, Q.: Paleoatmospheric
pCO2 fluctuations across the Cretaceous–Tertiary boundary recorded
from paleosol carbonates in NE China, Palaeogeogr. Palaeocl., 385, 95–105, 2013.
Hyland, E. G. and Sheldon, N. D.: Coupled CO2-climate response during
the early Eocene climatic optimum, Palaeogeogr. Palaeocl., 369, 125–135, 2013.
Hyland, E., Sheldon, N. D., and Fan, M.: Terrestrial paleoenvironmental
reconstructions indicate transient peak warming during the early Eocene
climatic optimum, GSA Bull., 125, 1338–1348, 2013.
Hyland, E. G., Huntington, K. W., Sheldon, N. D., and Reichgelt, T.: Temperature seasonality in the North American continental interior during the Early Eocene Climatic Optimum, Clim. Past, 14, 1391–1404, https://doi.org/10.5194/cp-14-1391-2018, 2018.
Inglis, G. N., Collinson, M. E., Riegel, W., Wilde, V., Farnsworth, A.,
Lunt, D. J., Valdes, P., Robson, B. E., Scott, A. C., Lenz, O. K., Naafs, B.
D. A., and Pancost, R. D.: Mid-latitude continental temperatures through the
early Eocene in western Europe, Earth Planet. Sc. Lett., 460, 86–96, 2017.
Jagniecki, E. A., Lowenstein, T. K., Jenkins, D. M., and Demicco, R. V.:
Eocene atmospheric CO2 from the nahcolite proxy, Geology, 43, 1075–1078,
2015.
Jones, S. M., Hoggett, M., Greene, S. E., and Jones, T. D.: Large Igneous
Province thermogenic greenhouse gas flux could have initiated
Paleocene-Eocene Thermal Maximum climate change, Nat. Commun., 10, 1–16, 2019.
Kastner, M., Kvenvolden, K. A., and Lorenson, T. D.: Chemistry, isotopic
composition, and origin of a methane-hydrogen sulfide hydrate at the
Cascadia subduction zone, Earth Planet. Sc. Lett., 156, 173–183, 1998.
Keeling, C. D., MOOK, W. G., and Tans, P. P.: Recent trends in the
13C
Kelson, J. R., Huntington, K. W., Schauer, A. J., Saenger, C., and Lechler,
A. R.: Toward a universal carbonate clumped isotope calibration: Diverse
synthesis and preparatory methods suggest a single temperature
relationship, Geochim. Cosmochim. Ac., 197, 104–131, 2017.
Kelson, J. R., Huntington, K. W., Breecker, D. O., Burgener, L. K.,
Gallagher, T. M., Hoke, G. D., and Petersen, S. V.: A proxy for all seasons?
A synthesis of clumped isotope data from Holocene soil
carbonates, Quaternary Sci. Rev., 234, 106259, https://doi.org/10.1016/j.quascirev.2020.106259, 2020.
Kistner, F. B.: Stratigraphy of the Bridger Formation in the Big Island-Blue
Rim area, Sweetwater County, Wyoming, Masters' Thesis, University of
Wyoming, Laramie, Wyoming, 1973.
Koenig, K. J.: Bridger Formation in the Bridger Basin, Wyoming, Overthrust Belt of Southwestern Wyoming and Adjacent Areas, 15th Annual Field Conference Guidebook, 163–168,
1960.
Komar, N., Zeebe, R. E., and Dickens, G. R.: Understanding long-term carbon
cycle trends: The late Paleocene through the early
Eocene, Paleoceanography, 28, 650–662, 2013.
Kowalczyk, J. B., Royer, D. L., Miller, I. M., Anderson, C. W., Beerling, D.
J., Franks, P. J., Grein, M., Konrad, W., Roth-Nebelsick, A., Bowring, S.
A., and Johnson, K. R.: Multiple proxy estimates of atmospheric CO2 from
an early Paleocene rainforest, Paleoceanogr. Paleocl., 33, 1427–1438, 2018.
Kowalski, E. A. and Dilcher, D. L.: Warmer paleotemperatures for terrestrial
ecosystems, P. Natl. Acad. Sci. USA, 100, 167–170, 2003.
Kuiper, K. F. A., Deino, F. J. K., Hilgen, W., Renne, P. R., and Wijbrans, J. R.:
Synchonizing rock clocks of Earth history, Science, 320, 500–504, 2008.
Leopold, E. B. and MacGinitie, H. D.: Development and affinities of Tertiary
floras in the Rocky Mountains, in: Floristics and Paleoflorists of Asia and Eastern North America, edited by: Graham, A., Elsevier
Publishing Company, 147–200, 1972.
Li, B., Nychka, D. W., and Ammann, C. M.: The value of multiproxy
reconstruction of past climate, J. Am. Stat. Assoc., 105, 883–895, 2010.
Liu, X. Y., Gao, Q., Han, M., and Jin, J. H.: Estimates of late middle Eocene pCO2 based on stomatal density of modern and fossil Nageia leaves, Clim. Past, 12, 241–253, https://doi.org/10.5194/cp-12-241-2016, 2016.
Looy, C., Kerp, H., Duijnstee, I., and DiMichele, B.: The late Paleozoic
ecological-evolutionary laboratory, a land-plant fossil record
perspective, Sediment. Record, 12, 4–18, 2014.
Lowenstein, T. K. and Demicco, R. V.: Elevated Eocene atmospheric CO2
and its subsequent decline, Science, 313, 1928–1928, 2006.
Lugo, A. E., Brown, S. L., Dodson, R., Smith, T. S., and Shugart, H. H.: The
Holdridge life zones of the conterminous United States in relation to
ecosystem mapping, J. Biogeogr., 26, 1025–1038, 1999.
Lunt, D. J., Ridgwell, A., Sluijs, A., Zachos, J., Hunter, S., and Haywood,
A.: A model for orbital pacing of methane hydrate destabilization during the
Palaeogene, Nat. Geosci., 4, 775–778, 2011.
MacGinitie, H. D.: The Eocene Green River flora of northwestern Colorado and northeastern Utah, University of California Press, Berkeley, California, USA 1969.
Manchester, S. R. and Zavada, M. S.: Lygodium foliage with intact sorophores from
the Eocene of Wyoming, Bot. Gaz., 148, 392–399, 1987.
Manchester, S. R., Judd, W. S., and Handley, B.: Foliage and fruits of early
poplars (Salicaceae: Populus) from the Eocene of Utah, Colorado, and
Wyoming, Int. J. Plant Sci., 167, 897–908, 2006.
Matthew, W. D.: The Carnivora and Insectivora of the Bridger basin, middle Eocene, EW Wheeler, printer, Bulletin of the American Museum of Natural History, New York, NY, 1909.
Maxbauer, D. P., Royer, D. L., and LePage, B. A.: High Arctic forests during
the middle Eocene supported by moderate levels of atmospheric
CO2, Geology, 42, 1027–1030, 2014.
Maxbauer, D. P., Feinberg, J. M., Fox, D. L., and Clyde, W. C.: Magnetic
minerals as recorders of weathering, diagenesis, and paleoclimate: A
core–outcrop comparison of Paleocene – Eocene paleosols in the Bighorn
Basin, WY, USA, Earth Planet. Sc. Lett., 452, 15–26, 2016.
Maynard, J. B.: Chemistry of modern soils as a guide to interpreting
Precambrian paleosols, J. Geol., 100, 279–289, 1992.
McElwain, J. C.: Do fossil plants signal palaeoatmospheric carbon dioxide
concentration in the geological past?, Philos. T. R. Soc. Lond. Ser. B, 353, 83–96, 1998.
McInerney, F. A. and Wing, S. L.: The Paleocene-Eocene Thermal Maximum: A
perturbation of carbon cycle, climate, and biosphere with implications for
the future, Annu. Rev. Earth Pl. Sc., 39, 489–516, 2011.
Meyer, R., Van Wijk, J., and Gernigon, L.: The North Atlantic Igneous
Province: A review of models for its formation, Special Papers-Geol. Soc. Am., 430, 525–552, 2007.
Milligan, J. N., Royer, D. L., Franks, P. J., Upchurch, G. R., and McKee, M.
L.: No evidence for a large atmospheric CO2 spike across the
Cretaceous-Paleogene boundary, Geophys. Res. Lett., 46, 3462–3472, 2019.
Murphey, P. C.: Stratigraphy, Fossil Distribution and Depositional Environments of the Upper Bridger Formation (Middle Eocene), Southwestern Wyoming, Doctoral Dissertation at University of Colorado at Boulder, Boulder, Colorado, USA, 2001.
Murphey, P. C. and Evanoff, E. M. M. E. T. T.: Paleontology and stratigraphy
of the middle Eocene Bridger Formation, southern Green River basin, Wyoming,
in: Proceedings of the Ninth Conference on Fossil Resources, Brigham Young University Geology Studies, 49, 83–109, 2011.
Murphey, P., Townsend, K. E., Friscia, A., Westgate, J., Evanoff, E., and
Gunnell, G.: Paleontology and stratigraphy of Middle Eocene rock units in the
southern Green River and Uinta Basins, Wyoming and Utah, Geology of the Intermountain West, 4, 1–53, 2017.
Nesbitt, H. and Young, G. M.: Early Proterozoic climates and plate motions
inferred from major element chemistry of lutites, Nature, 299, 715–717, 1982.
Norris, R. D., Jones, L. S., Corfield, R. M., and Cartlidge, J. E.: Skiing in the
Eocene Uinta Mountains? Isotopic evidence in the Green River Formation for
snow melt and large mountains, Geology, 24, 403–406, 1996.
Norris, R. D., Corfield, R. M., Hayes-Baker, K., Huber, B. T., MacLeod, K.
G., and Wing, S. L.: Mountains and Eocene climate, Huber, BT, MacLeod, KG, Wing, SL, 161–196, 2000.
Ong, H. L., Swanson, V. E., and Bisque, R. E.: Natural organic acids as
agents of chemical weathering, Geol. Surve. Res. Paper, 1970, C130–137, 1970.
Osborn, H. F.: Cenozoic mammal horizons of western North America, U.S. Geological Survey Bulletin, 361, 1–138,
1909.
Pagani, M., Zachos, J. C., Freeman, K. H., Tipple, B., and Bohaty, S.: Marked
decline in atmospheric carbon dioxide concentrations during the
Paleogene, Science, 309, 600–603, 2005.
Pagani, M., Pedentchouk, N., Huber, M., Sluijs, A., Schouten, S., Brinkhuis,
H., Damste, J. S. S., and Dickens, G. R.: Arctic hydrology during global
warming at the Palaeocene/Eocene thermal maximum, Nature, 442, 671–675, 2006.
Pagani, M., Huber, M., Liu, Z., Bohaty, S. M., Henderiks, J., Sijp, W.,
Krishnan, S., and DeConto, R. M.: The role of carbon dioxide during the onset
of Antarctic glaciation, Science, 334, 1261–1264, 2011.
Pälike, H., Lyle, M. W., Nishi, H., Raffi, I., Ridgwell, A., Gamage, K.,
Klaus, A., Acton, G., Anderson, L., Backman, J., Baldauf, J., and Zeebe, R.
E.: A Cenozoic record of the equatorial Pacific carbonate compensation
depth, Nature, 488, 609–614, 2012.
Pearson, P. N. and Palmer, M. R.: Atmospheric carbon dioxide concentrations
over the past 60 million years, Nature, 406, 695–699, 2000.
Peppe, D. J., Royer, D. L., Cariglino, B., Oliver, S. Y., Newman, S.,
Leight, E., Enikolopov, G., Fernandez-Burgos, M., Herrera, F., Adams, J. M.,
and Correa, E.: Sensitivity of leaf size and shape to climate: global
patterns and paleoclimatic applications, New Phytol., 190, 724–739, 2011.
Pett-Ridge, J. C., Monastra, V. M., Derry, L. A., and Chadwick, O. A.:
Importance of atmospheric inputs and Fe-oxides in controlling soil uranium
budgets and behavior along a Hawaiian chronosequence, Chem. Geol., 244, 691–707,
2007.
Poore, R. Z., Pavich, M. J., and Grissino-Mayer, H. D.: Record of the North
American southwest monsoon from Gulf of Mexico sediment
cores, Geology, 33, 209–212, 2005.
Reagan, M. K., McClelland, W. C., Girard, G., Goff, K. R., Peate, D. W.,
Ohara, Y., and Stern, R. J.: The geology of the southern Mariana fore-arc
crust: Implications for the scale of Eocene volcanism in the western
Pacific, Earth Planet. Sc. Lett., 380, 41–51, 2013.
Retallack, G. J.: Postapocalyptic greenhouse paleoclimate revealed by
earliest Triassic paleosols in the Sydney Basin, Australia, Geol. Soc. Am. Bull., 111, 52–70,
1999.
Retallack, G. J.: Soils of the past. An introduction to palaeopedology,
Blackwell Science Limited, Oxford, England, 2001.
Retallack, G. J.: Refining a pedogenic-carbonate CO2 paleobarometer to
quantify a middle Miocene greenhouse spike, Palaeogeogr. Palaeocl., 281, 57–65, 2009.
Roehler, H. W.: Eocene climates, depositional environments, and geography,
greater Green River Basin, Wyoming, Utah, and Colorado, United States Geological Survey, Professional Paper, 1–74, 1993.
Robinson, P., Gunnell, G. F., Walsh, S. L., Clyde, W. C., Storer, J. E.,
Stucky, R. K., Froehlich, D. J., Ferrusquia-Villafranca, I., and McKenna, M.
C.: Wasatchian through Duchesnean biochronology, Late Cretaceous and Cenozoic Mammals of North America, Columbia University Press, New York, 106–155, 2004.
Royer, D. L.: Depth to pedogenic carbonate horizon as a paleoprecipitation
indicator?, Geology, 27, 1123–1126, 1999.
Royer, D. L.: Estimating latest Cretaceous and Tertiary atmospheric CO2
from stomatal indices, in: Causes and Consequences of Globally Warm Climates in the Early Paleogene, edited by: Wing, S. L., Gingerich, P. D., Schmitz, B., and
Thomas, E., Geological Society of America Special Paper,
369, 79–93, 2003.
Royer, D. L., Wing, S. L., Beerling, D. J., Jolley, D. W., Koch, P. L.,
Hickey, L. J., and Berner, R. A.: Paleobotanical evidence for near
present-day levels of atmospheric CO2 during part of the
Tertiary, Science, 292, 2310–2313, 2001.
Sayyed, M. R. G. and Hundekari, S. M.: Preliminary comparison of ancient
bole beds and modern soils developed upon the Deccan volcanic basalts around
Pune (India): Potential for paleoenvironmental reconstruction, Quaternary Int., 156, 189–199,
2006.
Schiermeier, Q.: Global methane levels soar to record high, Nature, https://doi.org/10.1038/d41586-020-02116-8, 2020.
Shala, S., Helmens, K. F., Luoto, T. P., Salonen, J. S., Väliranta, M.,
and Weckström, J.: Comparison of quantitative Holocene temperature
reconstructions using multiple proxies from a northern boreal lake, The Holocene, 27,
1745–1755, 2017.
Sheldon, N. D., Retallack, G. J., and Tanaka, S.: Geochemical climofunctions
from North American soils and application to paleosols across the
Eocene-Oligocene boundary in Oregon, J. Geol., 110, 687–696, 2002.
Sheldon, N. D.: Abrupt chemical weathering increase across the
Permian–Triassic boundary, Palaeogeogr. Palaeocl., 231, 315–321, 2006.
Sheldon, N. D. and Tabor, N. J.: Quantitative paleoenvironmental and
paleoclimatic reconstruction using paleosols, Earth-Sci. Rev., 95, 1–52, 2009.
Sheldon, N. D., Smith, S. Y., Stein, R., and Ng, M.: Carbon isotope ecology
of gymnosperms and implications for paleoclimatic and paleoecological
studies, Glob. Planet. Change, 184, 103060, https://doi.org/10.1016/j.gloplacha.2019.103060, 2020.
Smith, M. E., Carroll, A. R., and Singer, B. S.: Synoptic reconstruction of a
major ancient lake system: Eocene Green River Formation, western United
States, GSA Bull., 120, 54–84, 2008.
Smith, M. E., Chamberlain, K. R., Singer, B. S., and Carroll, A. R.: Eocene
clocks agree: Coeval 40Ar
Smith, M. E., Carroll, A. R., Jicha, B. R., Cassel, E. J., and Scott, J. J.:
Paleogeographic record of Eocene Farallon slab rollback beneath western
North America, Geology, 42, 1039–1042, 2014.
Smith, M. E., Carroll, A. R., and Scott, J. J.: Stratigraphic expression of
climate, tectonism, and geomorphic forcing in an underfilled lake basin:
Wilkins Peak Member of the Green River Formation, in: Stratigraphy and Paleolimnology of the Green River Formation, Western USA,
Springer, Dordrecht, 61–102, 2015.
Smith, R. Y., Greenwood, D. R., and Basinger, J. F.: Estimating paleoatmospheric
pCO2 during the Early Eocene Climatic Optimum from stomatal frequency
of Ginkgo, Okanagan Highlands, British Columbia, Canada, Palaeogeogr. Palaeocl., 293, 120–131, 2010.
Smith, R. Y., Basinger, J. F., and Greenwood, D. R.: Early Eocene plant
diversity and dynamics in the Falkland flora, Okanagan Highlands, British
Columbia, Canada, Palaeobio. Palaeoenv., 92, 309–328, https://doi.org/10.1007/s12549-011-0061-5, 2012.
Snoke, A. W., Steidtmann, J. R., and Roberts, S. M.: Geologic history of
Wyoming within the tectonic framework of the North American
Cordillera, Geology of Wyoming: Geological Survey of Wyoming Memoir, 5, 2–56, 1993.
Soil Survey Staff: Keys to Soil Taxonomy, 12th Edn., USDA-Natural Resources
Conservation Service, Washington, DC, 2014.
Spicer, R. A., Valdes, P. J., Spicer, T. E. V., Craggs, H. J., Srivastava,
G., Mehrotra, R. C., and Yang, J.: New developments in CLAMP: calibration
using global gridded meteorological data, Palaeogeogr. Palaeocl., 283, 91–98, 2009.
Stein, R. and Sheldon, N.:Blue Rim escarpment geochemical data, Mendeley Data [data set], V2, https://doi.org/10.17632/z6twpstz4r.2, 2021.
Stein, R. A., Sheldon, N. D., and Smith, S.: Rapid response to anthropogenic
climate change by Thuja occidentalis: implications for past climate reconstructions and future
climate predictions, Peer J., 7, e7378, https://doi.org/10.7717/peerj.7378, 2019.
Stein, R. A., Sheldon, N. D., and Smith, S.: C3 plant carbon isotope
discrimination does not respond to CO2 concentration on decadal to
centennial timescales, New Phytol., 229, 2576–2585, https://doi.org/10.1111/nph.17030, 2021.
Steinthorsdottir, M., Vajda, V., Pole, M., and Holdgate, G.: Moderate levels
of Eocene pCO2 indicated by Southern Hemisphere fossil plant
stomata, Geology, 47, 914–918, 2019.
Storey, M., Duncan, R. A., and Tegner, C.: Timing and duration of volcanism
in the North Atlantic Igneous Province: Implications for geodynamics and
links to the Iceland hotspot, Chem. Geol., 241, 264–281, 2007.
Surdam, R. C. and Stanley, K. O.: Lacustrine sedimentation during the
culminating phase of Eocene Lake Gosiute, Wyoming (Green River
Formation), Geol. Soc. Am. Bull., 90, 93–110, 1979.
Tipple, B. J., Meyers, S. R., and Pagani, M.: Carbon isotope ratio of
Cenozoic CO2: A comparative evaluation of available geochemical
proxies., Paleoceanography, 25, 1–11, 2010.
Tu, T. N., Derenne, S., Largeau, C., Bardoux, G., and Mariotti, A.:
Diagenesis effects on specific carbon isotope composition of plant
n-alkanes, Org. Geochem., 35, 317–329, 2004.
Turner, G.: Argon 40-argon 39 dating: The optimization of irradiation
parameters, Earth Planet. Sc. Lett., 10, 227–234, 1971.
Van Houten, F. B.: Stratigraphy of the Willwood and Tatman formations in
northwestern Wyoming, Bull. Geol. Soc. Am., 55, 165–210, 1944.
Vinogradov, A. P.: Geochemistry of rare and dispersed chemical elements in
soils, Consultants Bureau, New York, 1959.
West, C. K., Greenwood, D. R., Reichgelt, T., Lowe, A. J., Vachon, J. M., and Basinger, J. F.: Paleobotanical proxies for early Eocene climates and ecosystems in northern North America from middle to high latitudes, Clim. Past, 16, 1387–1410, https://doi.org/10.5194/cp-16-1387-2020, 2020.
Westerhold, T., Rohl, U., Donner, B., and Zachos, J. C.: Global Extent of Early
Eocene Hyperthermal Events: A New Pacific Benthic Foraminiferal Isotope
Record from Shatsky Rise (ODP Site 1209), Paleoceanogr. Paleocl., 33, 626–642, 2018.
Wilf, P.: When are leaves good thermometers? A new case for leaf margin
analysis, Paleobiology, 23, 373–390, 1997.
Wilf, P., Wing, S. L., Greenwood, D. R., and Greenwood, C. L.: Using fossil
leaves as paleoprecipitation indicators: an Eocene
example, Geology, 26, 203–206, 1998.
Wilf, P.: Late Paleocene–early Eocene climate changes in southwestern
Wyoming: Paleobotanical analysis, Geol. Soc. Am. Bull., 112, 292–307, 2000.
Wing, S. L. and Greenwood, D. R.: Fossils and fossil climate: the case for
equable continental interiors in the Eocene, Philos. T. R. Soc. Lond. Ser. B, 341, 243–252, 1993.
Wing, S. L., Harrington, G. J., Smith, F. A., Bloch, J. I., Boyer, D. M.,
and Freeman, K. H.: Transient floral change and rapid global warming at the
Paleocene-Eocene boundary, Science, 310, 993–996, 2005.
Wing, S. L. and Currano, E. D.: Plant response to a global greenhouse event
56 million years ago, Am. J. Bot., 100, 1234–1254, 2013.
Witkowski, C. R., Weijers, J. W., Blais, B., Schouten, S., and Damsté,
J. S. S.: Molecular fossils from phytoplankton reveal secular PCO2 trend
over the Phanerozoic, Sci. Adv., 4, eaat4556, https://doi.org/10.1126/sciadv.aat4556, 2018.
Wolfe, J. A.: A method of obtaining climatic parameters from leaf
assemblages, United States Geological Survey Bulletin, 2040, 1–73, 1993.
Wolfe, J. A.: Temperature parameters of humid to mesic forests of eastern
Asia and relation to forests of other regions of the northern hemisphere and
Australasia, United States Geological Survey Professional Paper, 1106, 1–37, 1979.
Wolfe, J. A., Forest, C. E., and Molnar, P.: Paleobotanical evidence of
Eocene and Oligocene paleoaltitudes in midlatitude western North
America, Geol. Soc. Am. Bull., 110, 664–678, 1998.
Wood II, H. E., Chaney, R. W., Clark, J., Colbert, E. H., Jepsen, G. L.,
Reeside Jr., J. B., Stock, C., and Committee: Nomenclature and correlation of
the North American continental Tertiary, Bull. Geol. Soc. Am., 52, 1–48, 1941.
Zachos, J. C., Dickens, G. R., and Zeebe, R. E.: An early Cenozoic
perspective on greenhouse warming and carbon-cycle
dynamics, Nature, 451, 279–283, 2008.
Zeebe, R. E.: History of seawater carbonate chemistry, atmospheric CO2, and
ocean acidification, Annu. Rev. Earth Pl. Sci., 40, 141–165, 2012.
Zeebe, R. E., Zachos, J. C., and Dickens, G. R.: Carbon dioxide forcing alone
insufficient to explain Palaeocene–Eocene Thermal Maximum warming, Nat. Geosci., 2,
576–580, 2009.
Zhang, L., Wang, C., Wignall, P. B., Kluge, T., Wan, X., Wang, Q., and Gao,
Y.: Deccan volcanism caused coupled pCO2 and terrestrial temperature
rises, and pre-impact extinctions in northern China, Geology, 46, 271–274, 2018.
Zhu, J., Poulsen, C. J., and Tierney, J. E.: Simulation of Eocene extreme
warmth and high climate sensitivity through cloud feedbacks, Sci. Adv., 5,
eaax1874, https://doi.org/10.1126/sciadv.aax1874, 2019.
Short summary
Modern climate change drives us to look to the past to understand how well prior life adapted to warm periods. In the early Eocene, a warm period approximately 50 million years ago, southwestern Wyoming was covered by a giant lake. This lake and surrounding environments made for excellent preservation of ancient soils, plant fossils, and more. Using geochemical tools and plant fossils, we determine the region was a warm, wet forest and that elevated temperatures were maintained by volcanoes.
Modern climate change drives us to look to the past to understand how well prior life adapted to...
