Reactive greenhouse gas scenarios: Systematic exploration of uncertainties and the role of atmospheric chemistry

Knowledge of the atmospheric chemistry of reactive greenhouse gases is needed to accurately quantify the relationship between human activities and climate, and to incorporate uncertainty in our projections of greenhouse gas abundances. We present a method for estimating the fraction of greenhouse gases attributable to human activities, both currently and for future scenarios. Key variables used to calculate the atmospheric chemistry and budgets of major non‐CO2greenhouse gases are codified along with their uncertainties, and then used to project budgets and abundances under the new climate‐change scenarios. This new approach uses our knowledge of changing abundances and lifetimes to estimate current total anthropogenic emissions, independently and possibly more accurately than inventory‐based scenarios. We derive a present‐day atmospheric lifetime for methane (CH4) of 9.1 ± 0.9 y and anthropogenic emissions of 352 ± 45 Tg/y (64% of total emissions). For N2O, corresponding values are 131 ± 10 y and 6.5 ± 1.3 TgN/y (41% of total); and for HFC‐134a, the lifetime is 14.2 ± 1.5 y.

[1]  Stanley P. Sander,et al.  NASA Data Evaluation: Chemical Kinetics and Photochemical Data for Use in Atmospheric Studies , 2014 .

[2]  O. Edenhofer,et al.  Intergovernmental Panel on Climate Change (IPCC) , 2013 .

[3]  S. Dhomse,et al.  Using transport diagnostics to understand chemistry climate model ozone simulations , 2011 .

[4]  R. Stolarski,et al.  A model study of the impact of source gas changes on the stratosphere for 1850–2100 , 2011 .

[5]  K. Calvin,et al.  The RCP greenhouse gas concentrations and their extensions from 1765 to 2300 , 2011 .

[6]  A. Thomson,et al.  The representative concentration pathways: an overview , 2011 .

[7]  J. Lamarque,et al.  The HadGEM2-ES implementation of CMIP5 centennial simulations , 2011 .

[8]  Michael J. Prather,et al.  Uncertainties in climate assessment for the case of aviation NO , 2011, Proceedings of the National Academy of Sciences.

[9]  Malte Meinshausen,et al.  Future changes in global warming potentials under representative concentration pathways , 2011 .

[10]  G. Hegerl,et al.  Human contribution to more-intense precipitation extremes , 2011, Nature.

[11]  T. Wigley,et al.  Emulating coupled atmosphere-ocean and carbon cycle models with a simpler model, MAGICC6 - Part 1: Model description and calibration , 2011 .

[12]  P. Jöckel,et al.  Small Interannual Variability of Global Atmospheric Hydroxyl , 2011, Science.

[13]  Michael J. Prather,et al.  Coupling of Nitrous Oxide and Methane by Global Atmospheric Chemistry , 2010, Science.

[14]  David S. Lee,et al.  Historical (1850–2000) gridded anthropogenic and biomass burning emissions of reactive gases and aerosols: methodology and application , 2010 .

[15]  Malte Meinshausen,et al.  Uncertainties of global warming metrics: CO2 and CH4 , 2010 .

[16]  W. Landman.  Climate change 2007: the physical science basis , 2010 .

[17]  Ulrike Lohmann,et al.  A GCM study of future climate response to aerosol pollution reductions , 2010 .

[18]  J. Neu,et al.  An atmospheric chemist in search of the tropopause , 2010 .

[19]  Michael J. Prather,et al.  Global long‐lived chemical modes excited in a 3‐D chemistry transport model: Stratospheric N2O, NOy, O3 and CH4 chemistry , 2010 .

[20]  R. Langenfelds,et al.  The global SF6 source inferred from long-term high precision atmospheric measurements and its comparison with emission inventories , 2010 .

[21]  John F. B. Mitchell,et al.  The next generation of scenarios for climate change research and assessment , 2010, Nature.

[22]  Atul K. Jain,et al.  Tracking uncertainties in the causal chain from human activities to climate , 2009 .

[23]  R. Stolarski,et al.  Relationship of loss, mean age of air and the distribution of CFCs to stratospheric circulation and implications for atmospheric lifetimes , 2008 .

[24]  Francis Zwiers,et al.  Climate change: Attributing cause and effect , 2008, Nature.

[25]  B. Santer,et al.  Human-Induced Changes in the Hydrology of the Western United States , 2008, Science.

[26]  C. Curry,et al.  Modeling the soil consumption of atmospheric methane at the global scale , 2007 .

[27]  Kaarle Kupiainen,et al.  Scenarios of global anthropogenic emissions of air pollutants and methane until 2030 , 2007 .

[28]  R. Dickinson,et al.  Couplings between changes in the climate system and biogeochemistry , 2007 .

[29]  M. Prather.  Lifetimes and time scales in atmospheric chemistry , 2007, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences.

[30]  Vincent R. Gray.  Climate Change 2007: The Physical Science Basis Summary for Policymakers , 2007 .

[31]  D. Lowe,et al.  Methane carbon isotope effects caused by atomic chlorine in the marine boundary layer: Global model results compared with Southern Hemisphere measurements , 2007 .

[32]  O. Edenhofer,et al.  Mitigation from a cross-sectoral perspective , 2007 .

[33]  H. L. Miller,et al.  Climate Change 2007: The Physical Science Basis , 2007 .

[34]  T. J. Wallington,et al.  Evaluated kinetic and photochemical data for atmospheric chemistry: Volume IV – gas phase reactions of organic halogen species , 2006 .

[35]  Paul Steele,et al.  Law Dome CO2, CH4 and N2O ice core records extended to 2000 years BP , 2006 .

[36]  T. Stocker,et al.  Atmospheric Methane and Nitrous Oxide of the Late Pleistocene from Antarctic Ice Cores , 2005, Science.

[37]  R. Sausen,et al.  Scientific issues in the design of metrics for inclusion of oxides of nitrogen in global climate agreements. , 2005, Proceedings of the National Academy of Sciences of the United States of America.

[38]  P. M. Lang,et al.  Conversion of NOAA atmospheric dry air CH4 mole fractions to a gravimetrically prepared standard scale , 2005 .

[39]  J. Randerson,et al.  Recent changes in the air‐sea gas exchange of methyl chloroform , 2004 .

[40]  V. L. Orkin,et al.  Chemical kinetics and photochemical data for use in atmospheric studies. Evaluation No. 14 (JPL Publication 02-25) , 2003 .

[41]  V. L. Orkin,et al.  Scientific Assessment of Ozone Depletion: 2010 , 2003 .

[42]  J. Houghton,et al.  Climate change 2001 : the scientific basis , 2001 .

[43]  Mark Lawrence,et al.  Interhemispheric di ff erences in the chemical characteristics of the Indian Ocean aerosol during INDOEX , 2002 .

[44]  J. Lelieveld,et al.  A 1°×1° resolution data set of historical anthropogenic trace gas emissions for the period 1890–1990 , 2001 .

[45]  Robert J. Scholes,et al.  The Carbon Cycle and Atmospheric Carbon Dioxide , 2001 .

[46]  Alexei G. Sankovski,et al.  Special report on emissions scenarios : a special report of Working group III of the Intergovernmental Panel on Climate Change , 2000 .

[47]  J. Lelieveld,et al.  Simulation of preindustrial atmospheric methane to constrain the global source strength of natural wetlands , 2000 .

[48]  Michael B. McElroy,et al.  Three-dimensional climatological distribution of tropospheric OH: Update and evaluation , 2000 .

[49]  Michael R. Gunson,et al.  Evaluation of source gas lifetimes from stratospheric observations , 1997 .

[50]  K. Hsu,et al.  RATE CONSTANTS AND TEMPERATURE DEPENDENCES FOR THE REACTIONS OF HYDROXYL RADICAL WITH SEVERAL HALOGENATED METHANES, ETHANES, AND PROPANES BY RELATIVE RATE MEASUREMENTS , 1995 .

[51]  B. Santer,et al.  Correlation methods in fingerprint detection studies , 1993 .

[52]  W. Demore.  Relative rate constants for the reactions of OH with methane and methyl chloroform , 1992 .

[53]  P. Fraser,et al.  Global average concentration and trend for hydroxyl radicals deduced from ALE/GAGE trichloroethane (methyl chloroform) data for 1978–1990 , 1992 .

[54]  Michael J. Prather,et al.  Tropospheric OH and the lifetimes of hydrochlorofluorocarbons , 1990 .