edu.ucar.opensky::articles:12607 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-26T03:47:34.546342 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.org/ark:/85065/d7fx7b8v Tropospheric ozone changes, radiative forcing and attribution to emissions in the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP) 2013-03-15T00:00:00Z publication https://n2t.org/ark:/85065/d7fx7b8v https://doi.org/10.5194/acp-13-3063-2013 Stevenson, D. author Young, P. author Naik, V. author Lamarque, Jean-François author Shindell, D. author Voulgarakis, A. author Skeie, R. author Dalsoren, S. author Myhre, G. author Berntsen, T. author Folberth, G. author Rumbold, S. author Collins, W. author MacKenzie, I. author Doherty, R. author Zeng, G. author Van Noije, T. author Strunk, A. author Bergmann, D. author Cameron-Smith, P. author Plummer, D. author Strode, S. author Horowitz, L. author Lee, Y. author Szopa, S. author Sudo, K. author Nagashima, T. author Josse, B. author Cionni, I. author Righi, M. author Eyring, V. author Conley, A. author Bowman, K. author Wild, O. author Archibald, A. author UCAR/NCAR - Library publisher Ozone (O₃) from 17 atmospheric chemistry models taking part in the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP) has been used to calculate tropospheric ozone radiative forcings (RFs). All models applied a common set of anthropogenic emissions, which are better constrained for the present-day than the past. Future anthropogenic emissions follow the four Representative Concentration Pathway (RCP) scenarios, which define a relatively narrow range of possible air pollution emissions. We calculate a value for the pre-industrial (1750) to present-day (2010) tropospheric ozone RF of 410 mW m⁻². The model range of pre-industrial to present-day changes in O₃ produces a spread (±1 standard deviation) in RFs of ±17%. Three different radiation schemes were used -- we find differences in RFs between schemes (for the same ozone fields) of ±10%. Applying two different tropopause definitions gives differences in RFs of ±3%. Given additional (unquantified) uncertainties associated with emissions, climate-chemistry interactions and land-use change, we estimate an overall uncertainty of ±30% for the tropospheric ozone RF. Experiments carried out by a subset of six models attribute tropospheric ozone RF to increased emissions of methane (44±12%), nitrogen oxides (31 ± 9%), carbon monoxide (15 ± 3%) and non-methane volatile organic compounds (9 ± 2%); earlier studies attributed more of the tropospheric ozone RF to methane and less to nitrogen oxides. Normalising RFs to changes in tropospheric column ozone, we find a global mean normalised RF of 42 mW m⁻² DU⁻¹, a value similar to previous work. Using normalised RFs and future tropospheric column ozone projections we calculate future tropospheric ozone RFs (mW m⁻²; relative to 1750) for the four future scenarios (RCP2.6, RCP4.5, RCP6.0 and RCP8.5) of 350, 420, 370 and 460 (in 2030), and 200, 300, 280 and 600 (in 2100). Models show some coherent responses of ozone to climate change: decreases in the tropical lower troposphere, associated with increases in water vapour; and increases in the sub-tropical to mid-latitude upper troposphere, associated with increases in lightning and stratosphere-to-troposphere transport. Climate change has relatively small impacts on global mean tropospheric ozone RF. UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact PDF Text theme Resource Type 2016-01-01T00:00:00Z publication Copyright Author(s) 2013. This work is distributed under the Creative Commons Attribution 3.0 License. None eng geoscientificInformation