naa a22 4500 530098598 20181026074615.0 cr unu---uuuuu 181026s2015 xx s 000 0 eng 10.3929/ethz-b-000101988 doi 10.5194/acp-15-5887-2015 doi (ETHRESEARCH)oai:www.research-collection.ethz.ch:20.500.11850/101988 Drivers of the tropospheric ozone budget throughout the 21st century under the medium-high climate scenario RCP 6.0 [Elektronische Daten] [Laura E. Revell, Fiona Tummon, Andrea; id_orcid 0000-0002-5916-4013 Stenke, Timofei Sukhodolov, Ancelin Coulon, Eugene Rozanov, Hella Garny, Volker Grewe, Thomas Peter] Atmos. chem. phys. Open access ethresearch Because tropospheric ozone is both a greenhouse gas and harmful air pollutant, it is important to understand how anthropogenic activities may influence its abundance and distribution through the 21st century. Here, we present model simulations performed with the chemistry-climate model SOCOL, in which spatially disaggregated chemistry and transport tracers have been implemented in order to better understand the distribution and projected changes in tropospheric ozone. We examine the influences of ozone precursor emissions (nitrogen oxides (NOx), carbon monoxide (CO) and volatile organic compounds (VOCs)), climate change (including methane effects) and stratospheric ozone recovery on the tropospheric ozone budget, in a simulation following the climate scenario Representative Concentration Pathway (RCP) 6.0 (a medium-high, and reasonably realistic climate scenario). Changes in ozone precursor emissions have the largest effect, leading to a global-mean increase in tropospheric ozone which maximizes in the early 21st century at 23% compared to 1960. The increase is most pronounced at northern midlatitudes, due to regional emission patterns: between 1990 and 2060, northern midlatitude tropospheric ozone remains at constantly large abundances: 31% larger than in 1960. Over this 70-year period, attempts to reduce emissions in Europe and North America do not have an effect on zonally averaged northern midlatitude ozone because of increasing emissions from Asia, together with the long lifetime of ozone in the troposphere. A simulation with fixed anthropogenic ozone precursor emissions of NOx, CO and non-methane VOCs at 1960 conditions shows a 6% increase in global-mean tropospheric ozone by the end of the 21st century, with an 11 % increase at northern midlatitudes. This increase maximizes in the 2080s and is mostly caused by methane, which maximizes in the 2080s following RCP 6.0, and plays an important role in controlling ozone directly, and indirectly through its influence on other VOCs and CO. Enhanced flux of ozone from the stratosphere to the troposphere as well as climate change-induced enhancements in lightning NOx emissions also increase the tropospheric ozone burden, although their impacts are relatively small. Overall, the results show that under this climate scenario, ozone in the future is governed largely by changes in methane and NOx; methane induces an increase in tropospheric ozone that is approximately one-third of that caused by NOx. Climate impacts on ozone through changes in tropospheric temperature, humidity and lightning NOx remain secondary compared with emission strategies relating to anthropogenic emissions of NOx, such as fossil fuel burning. Therefore, emission policies globally have a critical role to play in determining tropospheric ozone evolution through the 21st century. Creative Commons Attribution 3.0 Unported http://creativecommons.org/licenses/by/3.0 ethresearch Revell Laura E. joint author Tummon Fiona joint author Stenke Andrea; id_orcid 0000-0002-5916-4013 joint author Sukhodolov Timofei joint author Coulon Ancelin joint author Rozanov Eugene joint author Garny Hella joint author Grewe Volker joint author Peter Thomas joint author Atmospheric Chemistry and Physics Göttingen : Copernicus 15 (10), pp. 5887-5902 1680-7375 http://hdl.handle.net/20.500.11850/101988 text/html WWW-Backlink auf das Repository (Open access) 1 Journal Article ethresearch ETHRESEARCH 856 40 http://hdl.handle.net/20.500.11850/101988 text/html WWW-Backlink auf das Repository (Open access) ETHRESEARCH 700 1- Revell Laura E. joint author ETHRESEARCH 700 1- Tummon Fiona joint author ETHRESEARCH 700 1- Stenke Andrea; id_orcid 0000-0002-5916-4013 joint author ETHRESEARCH 700 1- Sukhodolov Timofei joint author ETHRESEARCH 700 1- Coulon Ancelin joint author ETHRESEARCH 700 1- Rozanov Eugene joint author ETHRESEARCH 700 1- Garny Hella joint author ETHRESEARCH 700 1- Grewe Volker joint author ETHRESEARCH 700 1- Peter Thomas joint author ETHRESEARCH 773 0- Atmospheric Chemistry and Physics Göttingen : Copernicus 15 (10), pp. 5887-5902 1680-7375 BK010053 XK010053 XK010000 ETHRESEARCH ETHRESEARCH ETHRESEARCH Journal Article Open access