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Haqq-Misra et al. (2011) Haqq-Misra, J., J.F. Kasting, and S. Lee, Availability of O2 and H2O2 on the pre-photosynthetic Earth, Astrobiology 11, 293-302 (2011).

Here we pursued the claim by some biologists that aerobic respiration may have preceded photosynthesis. We are able to deliver modest amounts of O2 and H2O2 to the surface of a hypothetical prebiotic Earth based on atmospheric chemistry and a 3-D transport model.

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Kasting (2011) Kasting, J. F., Habitable planets: What are we learning from Kepler and ground-based searches? Astrobiology 11, 363-366 (2011).

A brief essay on what we know, and don't know about habitable exoplanets, based on ongoing searches.

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Roberson et al. (2011) Roberson, A. L., J. Roadt, I. Halevy, and J. F. Kasting, Greenhouse warming by nitrous oxide and methane in the Proterozoic Eon, Geobiology 9, 313-320 (2011).

In this paper we investigated Roger Buick's hypothesis that N2O might have been an important greenhouse gas during the Proterozoic. We get possibly a few degrees of warming out of N2O. We also redid our previous calculations for Proterozoic CH4, correcting for the error in the absorption coefficients.

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Dauphas and Kasting (2011) N. Dauphas and J. F. Kasting, Low pCO2 in the pore water, not in the Archean air (Comment on Rosing et al., 2010), Nature 474, E2-E3 (2011). (Available on request).

Here, we argued that the upper limit on Archean pCO2 of 3 times present published by Rosing et al. based on the analysis of mineral equilibria in banded iron-formations is invalid. Two other critical comments were published along with ours. The faint young Sun problem would be hard to solve if Rosing et al. were right, but we think they are not.

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Edson et al. (2011) Edson, A., S. Lee, P. Bannon, J.F. Kasting, and D. Pollard, Atmospheric circulations of terrestrial planets orbiting low-mass stars, Icarus 212, 1-13 (2011). (Available on request)

In this paper, which was part of Adam Edson's Ph.D. thesis, we looked at atmospheric circulation on tidally locked (synchronously rotating) planets around late-K and M stars. Dry and aqua-planets at Earth-equivalent distance were examined. The dynamical patterns change dramatically at an orbital period of around 4-5 days.

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Zugger et al. (2010) Zugger, M. E., J. F. Kasting, D. M. Williams, T. J. Kane, C. R. Philbrick, Light scattering from exoplanet oceans and atmospheres, Ap. J. 723, 1168-1179 (2010).

Here we looked at polarization signals from hypothetical exoplanets and decided, unfortunately, that it would be difficult to use this information to search for the presence of liquid water on a planet's surface.

 

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Tian et al. (2010) Tian, F., M. W. Claire, J. D. Haqq-Misra, M. Smith, D. C. Crisp, D. Catling, K. Zahnle, and J. F. Kasting, Photochemical and climate consequences of sulfur outgassing on early Mars, Earth Planet. Sci. Lett. 295, 412-418 (2010).

This paper was a response to the Halevy et al. 2007 Science paper on warming early Mars with SO2. We find that photolysis of SO2 leads to sulfate aerosol formation, even if the early martian atmosphere was reduced. The sulfate aerosols increase Mars' albedo and prevent this mechanism from producing significant surface warming.

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Nature N&V (2010) Kasting, J. F., Faint young Sun redux, Nature 464, 687-689 (2010).

This was a News and Views piece concerning the Rosing et al. paper on Archean pCO2 constraints from BIFs.

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Tian et al. (2009) Tian, F., J. F. Kasting, and S. C. Solomon, Fast thermal escape of carbon and oxygen from a dense, CO2-rich early martian atmosphere, Geophys. Res. Lett., 36, L02205, doi:10.1029/2008GL036513 (2009).

Here, we showed that both C and O could have escaped from Mars early in its history when the solar EUV flux was high. This may pose problems for building up a dense CO2 atmosphere. This can also lead to a possible "false positive" for O2, because C escapes faster than does O.

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Kasting (2008)  Kasting, J. F., Chapter 8: The primitive Earth, in Prebiotic Evolution and Astrobiology, J. T.-F. Wong and A. Lazcano, eds., Landes Bioscience, Austin, TX (2008).

A brief review chapter on the composition of Earth's early atmosphere.

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Haqq-Misra et al. (2008) Haqq-Misra, J. D., S. D. Domagal-Goldman, P. J. Kasting, and J. F. Kasting, A revised, hazy methane greenhouse for the early Earth, Astrobiol., 8, 1127-1137 (2008).

After finding a bug in our original methane greenhouse model, we corrected it and also extended the model by including greenhouse warming by ethane, C2H6. The new model is still consistent with constraints on atmospheric pCO2 from paleosols, but just barely. Organic haze exerts a strong cooling influence on the surface at CH4/CO2 ratios greater than ~0.1.

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Tian et al. (2008) Tian, F., J. F. Kasting, H. Liu, and R. G. Roble, Hydrodynamic planetary thermosphere model. I: The response of the Earth's thermosphere to extreme solar EUV conditions and the significance of adiabatic cooling, J. Geophys. Res. -- Planets, 113, E5 (May), E05008 (2008).

This is a model development paper in which we describe a model of the Earth's upper thermosphere that is appropriate for strongly heated conditions in which the atmosphere is expanding. It is designed to be used eventually to study hydrodynamic escape of hydrogen from the early Earth, Venus, and Mars.

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Domagal-Goldman, S. D., J. F. Kasting, D. T. Johnston, and J. Farquhar, Organic haze, glaciations and multiple sulfur isotopes in the Mid-Archean Era, Earth Planet. Sci. Lett. 269, 29-40 (2008). (Available on request)

Here, we argue that the decreased spread of D33S values between 2.8 and 3.2 Ga was likely caused by the buildup of organic haze in the atmosphere, not by a transient increase in atmospheric O2.

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Selsis et al. (2007) Selsis, F., J. F. Kasting, J. Paillet, and X. Delfosse, Habitable planets around the star Gl581? Astron. & Astrophys. 476, 1373-1387 (2007).

This paper examines the published claim that Gliese 581c, a planet orbiting a nearby M star, might be habitable. This planet receives 30% more starlight than Venus, so this is not likely to be the case. But other, potentially habitable M-star planets may soon be found.

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Segura et al. (2007) Kasting, J. F., A. Segura, V. S. Meadows, M. Cohen, and J. Scalo, Abiotic formation of O2 and O3 in high-CO2 terrestrial atmospheres, Astron. & Astrophys. 472, 665-679 (2007).

This paper was a response to concerns that buildup of abiotic O2 and O3 in the atmospheres of planets orbiting active young stars might lead to potential "false positives" for life when such planets are eventually viewed by TPF or Darwin. We argue that planets like Earth with liquid water on their surfaces are not likely to accumulate significant abiotic O2 or O3.

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Shields and Kasting (2007)  Shields, G. A. and J. F. Kasting, "Evidence for hot early oceans?" Nature 446, doi:10.1038/nature05830 (2007).

Here, we argue that the long-term trend in Si isotope ratios observed by Robert & Chaussidon (Nature, 2006) is caused by the same factors that caused oceanic O isotope ratios to change with time. Again, the conclusion is that the early Earth was not hot.

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Kasting (2006) Kasting, J. F., Earth Sciences - "Ups and downs of ancient oxygen", Nature 443, 643  (2006).

This was a News and Views article that commented on Goldblatt et al. (2006) and on Ohmoto's "yo-yo atmosphere" hypothesis.

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Kasting et al. (2006): Kasting, J. F., M. T. Howard, K. Wallmann, J. Veizer, G. Shields, and J. Jeffries, "Paleoclimates, ocean depth, and the oxygen isotopic composition of seawater", Earth Planet. Sci. Lett. 252, 82-93 (2006).

Here, we argue that the oxygen isotopic composition of seawater has changed with time as a consequence of tectonic changes associated with decreasing geothermal heat flow. Consequently, the high surface temperatures predicted from ancient cherts and carbonates should not be taken at face value.

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Pollard and Kasting (2006) David Pollard and James F. Kasting, "Reply to Comment by Steven G. Warren and Richard E. Brandt on 'Snowball Earth--a Thin-Ice Model with Flowing Sea Glaciers", J. Geophys. Res. 111, C09017, doi:10.1029/2006JC003488 (2006)

We respond to the criticism by these authors and also to another GRL paper by Jason Goodman. The thin-ice model is alive and well, but it works better on an Earth with continents than on a water-world. That's fine, as the Neoproterozoic Earth certainly had them..

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Kasting and Howard (2006): J. F. Kasting, M. T. Howard, "Atmospheric Composition and Climate on the Early Earth", Phil. Trans. R. Soc. B 361, 1733-1742 (2006)

Here, we present an alternative model (the organic haze model) for the 2.9-Ga mid-Archean glaciation. We also discuss the possibility that the 18O/16O ratio of seawater has changed with time. Details of both topics will be published elsewhere.


Kasting and Ono (2006): James F. Kasting, Shuhei Ono, "Palaeoclimates: the First Two Billion Years", Phil. Trans. R. Soc. B. 361, 917-929 (2006)

A review of paleoclimates in the distant past. But there is also some new material here. The sulfur low-MIF values between 2.8-3.2 Ga are correlated with the 2.9-Ga mid-Archean glaciation. Transient atmospheric oxidation caused by the origin of bacterial sulfate reduction is proposed as the cause. Stay tuned for an alternative explanation...


Segura et al._Astrobiology_05: Segura, A., J. F. Kasting, V. Meadows, M. Cohen, J. Scalo, D. Crisp, R. A. H. Butler, and G. Tinetti, "Biosignatures From Earth-like Planets Around M Dwarfs", Astrobiology 5, 706-725 (2005)

This was a follow-up to Segura et al. (2003). Here, we used the same coupled photochemical-climate model to look at planets around M stars. High concentrations of CH4, N2O, and other trace gases are predicted.


Kharecha et al. Geobiology_05: P. Kharecha, J. F. Kasting, and J. L. Siefert, "A Coupled Atmosphere-ecosystem Model of the Early Archean Earth", Geobiology 3, 53-76 (2005)

This paper, which is based on Pushker's Ph.D. thesis, describes a coupled model that is used to predict primary productivity and methane fluxes in an anaerobic Archean biosphere.


Pollard&Kasting_JGR_05: David Pollard and J.F. Kasting. "Snowball Earth: A thin-ice solution with flowing sea glaciers"  Journal of Geophysical Research vol. 110 (July 2005)

   This paper provides new support for Chris McKay's "thin-ice" model for Neoproterozoic Snowball Earth glaciations, answering criticisms from Goodman and Pierrehumbert and from Steve Warren et al.


Precambrian_Res_05: J.F. Kasting. "Methane and climate during the Precambrian era"  Precambrian Research 137: 119-129 (March 2005)

    A review paper on methane and climate in the Precambrian.


Scientific_American_04: J.F. Kasting. "When Methane Made Climate"  Scientific American: 80-85 (July 2004)

    This paper tells the story of how methane could have controlled Earth's climate during the Archean and Proterozoic eras.


Nature_04: J.F. Kasting. "Archean Atmosphere and Climate"  Nature 432: 1 (November 2004)

    This is a comment on a paper by H. Ohmoto and colleagues in which I argue that high CO2 in the Archean does not mean that CH4 must have been low.


Bull._Amer._Meteorol._Soc._03: J.F. Kasting. "Review of Snowball Earth: The Story of the Great Global Catastrophe that Spawned Life as We Know It"  Bull. Amer. Meteorol. Soc. 84: 1,581-1,584 (2003)

    This is a review of Gabrielle Walker's "Snowball Earth" book.


Segura_et_al_Astrobiology_03: A. Segura et al. "Ozone Concentrations and Ultraviolet Fluxes on Earth-like Planets Around Other Stars Astrobiology 3: 689-708 (2003)

    In this paper, we calculate what the Earth would look like spectroscopically around different types of stars (F, G, and K) and for different O2 levels. We also estimate surface UV fluxes and dose rates for DNA damage and erythema.


Geology_03: A.A. Pavlov et al. "Methane-Rich Proterozoic Atmosphere?"  Geology 31: 87-90 (2003) (Available on request)

    A speculative argument that methane may have played an important role in warming the Proterozoic atmosphere, after the initial rise in atmospheric O2.


Annurev_03: J.F. Kasting, D. Catling. "Evolution of a Habitable Planet"  Ann. Rev. Atron. Astrophys. 41: 429-463 (2003)

    This is a review article covering issues related to water delivery to Earth, long-term climate evolution, the atmospheric redox budget, and the rise of atmospheric oxygen and ozone.


Earth_Planet._Sci._Lett._03: Shuhei Ono et al. "New Insights into Archean Sulfur Cycle from Mass-Independent Sulfur Isotope Records"  Earth Planet. Sci. Lett. 213: 15-30 (2003)

    This paper presents new data on mass-independently fractionated sulfur isotopes in Archean sediments, along with some interpretations on how they got to be that way. Such isotope fractionation patterns are thought to be a signal of low atmospheric O2.


Astrobiology_02: A.A. Pavlov, J.F. Kasting. "Mass-Independent Fractionation of Sulfur Isotopes in Archean Sediments: Strong Evidence for an Anoxic Archean Atmosphere"  Astrobiology 2: 27-41 (2002)

    Here, we used a photochemical model--two of them, actually--to place constraints on past atmospheric O2 levels prior to ~2.3 Ga based on the data showing mass-independently fractionated sulfur isotopes in rocks older than this. The upper limit we found was 10-5 PAL (times the Present Atmospheric Level), but a more realistic estimate is 10-13 PAL.


Astrobiology_DesMarais_02: D.J. Desmarais et al. "Remote Sensing of Planetary Properties and Biosignatures on Extrasolar Terrestrial Planets"  Astrobiology 2: 153-181 (2002)

    This paper was written by the Biomarkers Subcommittee of the Terrestrial Planet Finder Science Working Group. It provides a thorough discussion of they types of information that can be extracted by remote sensing of extrasolar planet atmospheres.


Science_02: J.F. Kasting, J. L. Siefert. "Life and the Evolution of Earth's Atmosphere"(Perspective) Science 296: 1,066-1,068 (2002)

    A Perspective article covering CH4-rich Archean atmospheres and the rise of O2.


J._Geophys._Res._01: A.A. Pavlov, L.L. Brown, J.F. Kasting. "Shielding of NH3 and O2 by Organic Hazes in the Archean Atmosphere"  J. Geophys. Res. 106: 23,267-23,287 (2001)

    Here, we used a 1-D photochemical model to explore the photochemistry of methane in an anoxic early Earth atmosphere. We showed that hydrocarbon haze should form if the atmospheric CH4/CO2 ratio was greater than ~0.6.


Perspectives_In_Biology_and_Medicine_01: J.F. Kasting. "Essay Review of Peter Ward and Don Brownlee's Rare Earth: Why Complex Life is Uncommon in the Universe"  Perspectives in Biology and Medicine 44: 117-131 (2001)

    This was a detailed, point-by-point review of Ward and Brownlee's "Rare Earth" hypothesis. I argued that they were overly pessimistic about the prospects for finding complex life (animals) on other planets.


Orig._Life_Evol._Biosphere_01: J.F. Kasting, A.A. Pavlov, J. L. Siefert. "A Coupled Ecosystem-Climate Model for Prediciting the Methane Concentration in the Archean Atmosphere"  Orig. Life Evol. Biosphere 31: 271-285 (2001)

    Here, we used thermodynamic and climate constraints to predict the methane concentration in the Archean atmosphere. Look for a more up-to-date paper by Kharecha et al. coming out in 2004 or 2005.


Nature_01: J.F. Kasting, J.L. Siefert. "The Nitrogen Fix" (News and Views Article) Nature 412: 26-27 (2001)

    A News and Views article discussion the origins of nitrogen fixation.


Science_01: J.F. Kasting. "The Rise of Atmospheric Oxygen" (Perspective) Science 293: 819-820 (2001)

    A Perspective article discussing the Catling et al. paper on the rise of atmospheric O2 and the Farquhar et al. paper on mass-independently fractionated sulfur isotopes in ancient rocks (which also bear on the rise of O2).


Geology_01: A.A. Pavlov et al. "Hydrocarbon Aerosols as a Source of Low-13C Kerogens in Archean Sediments"  Geology 29: 1,003-1,006 (2001)                 (Available on request)

    An argument that the extremely 13C-depleted kerogens in 2.7 b.y.-old  sediments may be remnants of hydrocarbon smog produced by photolysis of CH4.


G^3_01: L.R. Kump, J.F. Kasting, M.E. Barley. "The Rise of Atmospheric Oxygen and the "Upside-Down" Archean Mantle"  Geochem. Geophys. Geosyst. 2: Paper #2000GC000114 (2001)

    A discussion of the possibility that hydrogen escape to space could have led to progressive oxidation of the upper mantle, thereby triggering the rise in atmospheric O2 at ~ 2.3 Ga.


J._Geophys_Res._00: A.A. Pavlov et al. "Greenhouse Warming by CH4 in the Atmosphere of Early Earth"  J. Geophys. Res. 105: 11,981-11,990 (2000)

    In this paper, we used a 1-D radiative-convective climate model to calculate surface temperatures in the distant past for different combinations of atmospheric CO2 and CH4. The general conclusion is that methane could have provided much of the greenhouse warming required to offset lower solar luminosity, i.e., to resolve the faint young Sun problem.


Icarus_00: T.L. Schindler, J.F. Kasting. "Synthetic Spectra of Simulated Terrestrial Atmospheres Containing Possible Biomarker Gases"  Icarus 145: 262-271 (2000)

    In this paper, we looked at possible biosignature gases on Earth-like planets. In particular, we showed that methane ought to be visible in the thermal-IR on a planet that resembles the early Earth.


Icarus_00-Mischna: Michael A. Mischna et al. "Influence of Carbon Dioxide Clouds on Early Martian Climate" Icarus 145: 546-554 (2000)

    In this paper, we showed that CO2 ice clouds can cool a planet's surface, as well as warm it, if they are either low or optically thick. We also showed that the outer edge of the present habitable zone around the Sun could lie out as far as 2.0 AU.


Consequences_98: J.F. Kasting. "Long-term Effects of Fossil Fuel Burning"  Consequences 4: 15-27 (1998)

    Here, I discuss the long-term consequences of adding fossil-fuel CO2 to the atmosphere. I argue that it makes economic sense to keep CO2 levels contained. Discounting is a key factor: long-term discount rates cannot be set too high, or future catastrophes do not matter. Based on a technical paper by Schultz & Kasting (1996).


Nature_98: D.M. Williams, J.F. Kasting, L.A. Frakes. "Were Low-Latitude Precambrian Glaciations Caused by High Obliquity"  Nature 396: 453-455 (1998)

    Our last-gasp attempt to justify the high-obliquity hypothesis for low-latitude Precambrian glaciations. This paper was written before Paul Hoffman's Snowball Earth paper appeared. I am now a firm believer in the Snowball Earth hypothesis, so look for the negatives in this paper, specifically, the screwy phase relationships that are required in order to make the 'climate friction' mechanism work!.


Nature_97: D.M. Williams, J.F. Kasting, R.A. Wade. "Habitable Moons Around Extrasolar Giant Planets"  Nature 385: 234-236 (1997)

    Here, we explore the possibility of habitable moons around extrasolar giant planets. The motivation for this paper came from watching Star Wars III, in which the critical battle was fought on the moon Endor. Right, Darren?


OLEB_97: J.F.Kasting. "Habitable Zones Around Low Mass Stars and the Search for Extraterrestrial Life"  Origins of Life 27: 291-307 (1997)

    This paper reviews the topic of habitable zones around stars and discusses the question of biomarker gases in extrasolar planet atmospheres.


Energy_Policy_97: P.A. Schultz, J.F. Kasting. "Optimal Reductions in C02 Emissions"  Energy Policy 25: 491-500 (1997)

    An economic argument in favor of reducing CO2 emissions. We argue that previous studies of this type have underestimated the atmospheric lifetime of CO2. We also show that the economic discount rate is of key importance: global warming does not matter if you discount the future strongly.


Science_97: J.F. Kasting. "The Early Mars Climate Question Heats Up" (Perspective) Science 278: 1,245 (1997)

    A Perspective article on the Forget and Pierrehumbert article on the scattering greenhouse effect of CO2 ice clouds.


Science276_97: J.F. Kasting. "Warming Early Earth and Mars" (Perspective) Science 276: 1,213-1,215 (1997)

    A Perspective article on the Sagan and Chyba paper dealing with formation of hydrocarbon smog in CH4-rich primitive atmospheres on Earth and Mars.


Science_94: S.W. Squyres, J.F. Kasting. "Early Mars: How Warm and How Wet?"  Science 265: 744-749 (1994)

    A review article on early martian climate.


Icarus_93: J.F. Kasting, D.P. Whitmire, R.T. Reynolds. "Habitable Zones Around Main Sequence Stars" Icarus 101: 108-128 (1993)

    In this paper we attempted to estimate the width of the liquid-water habitable zone (HZ) around different types of main sequence stars. The biggest uncertainties in the calculations concern the feedback effect of clouds: H2O clouds on the inner edge, CO2 clouds on the outer edge. Ray Reynolds pointed out that CO2 condensation would determine the location of the outer edge of the HZ. Andy Ingersoll wrote the seminal paper on the runaway greenhouse, which determines the location of the inner edge. 


Nature_93: K. Caldeira, J.F. Kasting. "Insensitivity of Global Warming Potentials to Carbon Dioxide Emission Scenarios"  Nature 366: 251-253 (1993)

    A News&Views article commenting on Greg Jenkins 3-D GCM modeling of the faint young Sun problem.


J._Geol._93: J.P. Grotzinger, J.F. Kasting. "New Constraints on Precambrian Ocean Composition" J. Geol. 101: 235-243 (1993)

    In this paper we attempted to place limits on Precambrian ocean composition using constraints from evaporite deposits and from atmospheric/climate considerations.


J._Geol._93_Mantle Redox: J.F. Kasting, D.H. Eggler, S.P. Raeburn. "Mantle Redox Evolution and the Case for a Reduced Archean Atmosphere" J. Geol 101: 245-257 (1993)

    Here we argued that Earth's mantle should have become progressively more oxidized with time as a consequence of loss of hydrogen to space, and that this change could have altered the oxidation state of volcanic gases and helped to trigger the rise of atmospheric O2 at ~2.3 Ga.


Science_93: J.F. Kasting. "Earth's Early Atmosphere"  Science 259: 920-926 (1993)

    A review paper on long-term evolution of Earth's atmosphere, covering both climate and atmospheric composition.


Walker and Kasting (1992): Walker, J.C.G. and J.F. Kasting, "Effect of forest and fuel conservation on future levels of atmospheric carbon dioxide" Palaeogeogr. Palaeoclimat. Palaeoecol. (Global Planet. Change Sect.) 97: 151-189. (1992)

    In this paper, we burn up the entire economically recoverable fossil fuel inventory over the next few hundred years and explore the consequences for atmospheric CO2 and climate. CO2 concentrations exceeding 2000 ppmv are possible. The impact of CO2 fertilization of plant growth is probably overestimated in this paper, so the actual climate situation in the distant future could be even worse than predicted here.


Earth_Planet._Sci._Lett._92: J.F. Kasting, N.G. Holm. "What Determines the Volume of the Oceans" Earth Planet. Sci. Lett. 109: 507-515 (1992)

    In this paper, I argued that the volume of the oceans is controlled by a negative feedback mechanism that controls exchange of water between the crust and the mantle.


Nature_92: K.Caldeira, J.F. Kasting, "Susceptibility of the Early Earth to Irreversible Glaciation Cause by Carbon Dioxied Clouds" Nature 359: 226-228 (1992)

    In this paper we used an energy balance climate model (EBM) to study the question of how Earth could have escaped from global glaciation. It does so be building up volcanic CO2 in its atmosphere. Although we were unaware of the evidence for Snowball Earth episodes at this time, this model is applicable to those situations.


Nature360_92: K.Caldeira, J.F. Kasting, "The Life Span of the Biosphere Revisited"  Nature 360: 721-723 (1992)

    Here, we used a coupled climate/geochemical cycle model to predict atmospheric CO2 levels and climate in the distant future. In our model, solar luminosity increases cause CO2 to drop below 150 ppmv, the threshold for C3 photosynthesis, in about 500 million years.


Icarus_91: J.F. Kasting. "C02 Condensation and the Climate of Early Mars"  Icarus 94: 1-13 (1991)

    Here, I showed that CO2 by itself could not have provided enough greenhouse effect to keep the mean temperature of early Mars above the freezing point of water.


Origins_of_Life_90: J.F. Kasting. "Bolide Impacts and the Oxidation State of Carbon in the Earth's Early Atmosphere" Origins of Life 20: 199-231 (1990)

    Here, I used a 1-D photochemical model to illustrate the effects of bolide impacts on atmospheric composition during the heavy bombardment period prior to ~3.8 Ga. The existence of an extended period of heavy bombardment remains controversial; some researchers think it was just a big pulse. The main chemical effect is production of CO, which can accumulate to seriously high concentrations (several bars) in the atmosphere if it is not consumed in the oceans.


Origins of Life_89: J.F. Kasting, K.J. Zahnle, J.P. Pinto, and A.T. Young. "Sulfur, ultraviolet radiation, and the early evolution of life" Origins of Life 19: 95-108 (1989).

   In this paper, we showed that S8 could, in principle, have provided a UV screen for the early Earth, but only if the surface temperature was high (>45oC) and if the oceans were saturated in S(IV), i.e. SO2 and its dissociation products. There was supposed to have been a longer sulfur paper, but it never got published. The sulfur photochemical scheme can be found in Origins of Life (1990), directly above.

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Nature_89: N. H. Sleep, K. J. Zahnle, J. F. Kasting, and H. J. Morowitz. "Annihilation of Ecosystems by Large Asteroid Impacts on the Early Earth"  Nature 342: 139-142 (1989)

    In this paper, we estimated the frequency of occurrence of large impacts on the early Earth and analyzed their possible environmental effects. A 440-km diameter asteroid would have vaporized the entire ocean.


Icarus_88: J.F. Kasting. "Runaway and Moist Greenhouse Atmospheres and the Evolution of Earth and Venus"  Icarus 74: 472-494 (1988)

    In this paper, I used a 1-D radiative-convective climate model to study the runaway greenhouse effect, building on previous work by Andy Ingersoll. The model also predicts that the oceans can be lost via a 'moist greenhouse effect', in which oceans are still present throughout much of the period during which water was lost.


Scientific_American_88: J.F. Kasting et al. "How Climate Evolved on the Terrestrial Planets"  Scientific American 256: 90-97 (1988)

    In this paper, we compare how climate evolved on Venus, Earth, and Mars. I still agree with most of this; however, CO2 by itself could not have kept early Mars warm (see Icarus, 1991, paper).


Precambrian_Res._87: J.F. Kasting. "Theoretical Constraints on Oxygen and Carbon Dioxide Concentrations in the Precambrian Atmosphere"  Precambian Res. 34: 205-228 (1987)

    In this paper, I tried to make estimates of CO2 and O2 levels in the distant past, based on theoretical considerations and observational constraints.


Science_86: J.F. Kasting, T.P. Ackerman. "Climatic Consequences of Very High C02 Levels in Earth's Early Atmosphere"  Science 234: 1,383-1385 (1986)

    In this paper we showed that Earth's atmosphere would not experience a runaway greenhouse even with a 100-bar CO2 atmosphere. A follow-up on Jim Walker's paper suggesting that CO2 levels of 10 bars or more could have been present in Earth's atmosphere during the first few hundred million years of its history.


J. Atmos. Chem._84 Kasting, J.F., J.B. Pollack, and D. Crisp. "Effects of high CO2 levels on surface temperature and atmospheric oxidation state on the early earth.",  J. Atmos. Chem. 1: 403‑428 (1984)

  This paper was primarily devoted to calculating the climatic effects of high CO2 levels early in Earth's history. Dave Crisp's band model formulation for CO2 absorption was used in these calculations. The paper also included a rudimentary treatment of the atmospheric hydrogen budget, in which rainout of H2O2 and H2CO were included.


Icarus_83 Kasting, J.F. and J.B. Pollack. Loss of water from Venus. I. Hydrodynamic escape of hydrogen. Icarus 53: 479-508 (1983).

  This paper examined subsonic hydrodynamic escape solutions from a water-rich primitive Venusian atmosphere. The vertical coordinate was l = 1/r. The basic methodology was duplicated later in Tian et al. (2008) (see above), although the Tian et al. model used a time-stepper to solve the energy equation.


J._Geophys._Res._81: J.F. Kasting and J.C.G. Walker. "Limits on Oxygen Concetration in the Prebiological Atmosphere and the Rate of Abiotic Fixation of Nitrogen"  J. Geophys. Res. 86: 9,776-9,782 (1981)

    A second paper on early atmospheric composition in which we included odd nitrogen photochemistry and looked at the atmospheric nitrogen cycle.


J._Geophys._Res.86_81: J.C.G Walker, P.B. Hays, J.F. Kasting. "A Negative Feedback Mechanism for the Long-term Stabilization of Earth's Surface Temperature"  J. Geophys. Res. 86: 1,147-1,158 (1981)

        Here, we suggested for the first time that Earth's long-term climate was buffered by a negative feedback mechanism involving atmospheric CO2 levels and the dependence of silicate weathering rates on climate.

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J._Geophys._Res._80: J.F. Kasting and T.M. Donahue. "The Evolution of the Atmospheric Ozone"  J. Geophys. Res. 85: 3,255-3,263 (1980)

    In this paper, I used a 1-D photochemical model to study the rise of atmospheric ozone. Atmospheres with O2 levels from 1 PAL (times the Present Atmospheric Level) down to 10-5 PAL were studied.


J._Geophys._Res._79:  J.F. Kasting, S.C. Liu, T.M. Donahue. "Oxygen Levels in the Prebiological Atmosphere"  J. Geophys. Res. 84: 3,097-3107 (1979)

    Here I explored (for the first time) the photochemistry of the early atmosphere using a 1-D photochemical model. I showed that surface O2 concentrations should have been very low, in agreement with predictions made by Jim Walker in his 1977 book.


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