Chapter 3: Future Ozone and Its Impact on Surface UV

S. BEKKI; G. BODECKER ; A.F. BAIS; N. BUTCHART; V. EYRING; D.W. FAHEY; D.E. KINNISON; U. LANGEMATZ; B. MAYER; R.W. PORTMANN; E. ROZANOV; P. BRAESICKE; A.J. CHARLTON-PEREZ; N.E. CHUBAROVA; I. CIONNI; S.B. DIAZ; ET AL

Scientific Assessment on ozone Depletion 2010. Global Ozone Research and Monitoring Project–Report No. 52

World Meteorological Organization

Lugar: Ginebra; Año: 2011; p. 1 - 60

ESTE LIBRO ES UNA ACTUALIZACION DE LA SITUACION DE LA CAPA DE OZONO Y SIRVE COMO BASE PARA QUE LOS TOMADORES DE DECISIONES DE PAISES DE TODO EL MUNDO LLEVEN A CABO LAS MEDIDAS NECESARIAS PARA LA RECUPERACION Y PRESERVACION DE LA CAPA DE OZONO. LO CUAL NO SOLO AFECTA A LA CAPA DE OZONO, SINO, TAMBIEN AL CAMBIO CLIMATICO. ESTOS INFORMES SE REALIZAN POR MANDATO DEL PROTOCOLO DE MONTREAL (1987) Y SE REALIZAN GENERALMENTE CADA 4 AÑOS. EL PROCESO DE ELABORACION DEL MISMO LLEVA MAS DE 2 AÑOS. CADA CAPITULO PASA POR PROCESO DE REVISION POR PARTE DE CIENTIFICOS DE TODO EL MUNOD EN 3 ETAPAS DE SU ELABORACION, SEGUN SE CONSIGNA EN EL INFORME. LA AUTORIA DE LOS CAPITULOS ES POR INVITACION, REALIZADA POR LA ORGANIZACION METEOROLOGICA MUNDIAL Y EL PROGRAMA DE NACIONES UNIDAS PARA EL MEDIO AMBIENTE. EXCEPTO POR LOS "COORDINATING LEAD AUTHORS" Y LOS "LEAD AUTHORS", LOS AUTORES ESTAN UBICADOS POR ORDEN ALFABETICO. Sólo se consignaron los nombre de los autores hasta el investigador al que pertenece esta producción científica, como autor número 17 se consignó “et al”. "The first drafts of the chapters were examined at a meeting that occurred on 17–19 November 2009 in Fairfax, Virginia, United States, at which the Coordinating Lead Authors, Cochairs, and a small group of international experts focused on the scientific content of the draft chapters. The second drafts of the chapters were reviewed by 122 scientists worldwide in a mail peer review. Those comments were considered by the authors. At a Panel Review Meeting in Les Diablerets, Switzerland, held on 28 June–2 July 2010, the responses to these mail review comments were proposed by the authors and discussed by the 74 participants. Final changes to the chapters were decided upon at this meeting". The present document will be part of the information upon which the Parties to the United Nations Montreal Protocol will base their future decisions regarding protection of the stratospheric ozone layer. . To meet this request, the Scientific Assessment Panel prepared, about every 3-4 years, major assessment reports that updated the state of understanding  and its purviews. These reports are prepared by the world’s leading experts in the atmospheric sciences and under the international auspices of the World Meteorological Organization (WMO) and/or the United Nations Environment Programme UNEP). The formal planning of the current assessment was started early in 2009. The Cochairs considered suggestions from the Parties regarding experts from their countries who could participate in the process. Furthermore, an ad hoc international scientific advisory group also suggested participants from the world scientific community. The first drafts of the chapters were examined at a meeting that occurred on 17–19 November 2009 in Fairfax, Virginia, United States, at which the Coordinating Lead Authors, Cochairs, and a small group of international experts focused on the scientific content of the draft chapters. The second drafts of the chapters were reviewed by 122 scientists worldwide in a mail peer review. Those comments were considered by the authors. At a Panel Review Meeting in Les Diablerets, Switzerland, held on 28 June–2 July 2010, the responses to these mail review comments were proposed by the authors and discussed by the 74 participants. Final changes to the chapters were decided upon at this meeting. The primary goal of the Montreal Protocol and its Amendments and Adjustments is to avoid depletion of the ozone layer. Ozone depletion elevates surface ultraviolet (UV) radiation, thereby posing a threat to Earth’s biosphere. The mechanism used to achieve this goal is the control of the production and  consumption of anthropogenic ozone-depleting sustances. At present, throughout most of the stratosphere, equivalent stratospheric chlorine is significantly elevated above natural levels due to the cumulative effect of historical emissions of ODSs. Elevated ESC remains the most important anthropogenic perturbation to stratospheric ozone. However, as halogen loading declines in the future, other factors are expected to displace ODSs as the dominant influence on ozone. Perhaps the most important of these are continued and increasing emissions of long-lived greenhouse gases (GHGs). For example, GHGs affect ozone directly because they act as stratospheric source gases for ozone-destroying radicals (e.g., methane (CH4) and nitrous oxide (N2O)) and indirectly because they change temperatures (predominantly carbon dioxide (CO2)). This chapter builds on and extends Chapter 5 of the previous Ozone Assessment, 2007. by assessing the most  recent literature on the likely effects of increasing GHG emissions on future ozone amounts and resultant changes in climate parameters. It also assesses on chemistry-climate model (CCM) projections of the evolution of ozone through the 21st century. The number of available CCMs and CCM sensitivity simulations has significantly increased since the previous Assessment, now future ozone projections are obtained from the current generation of three-dimensional CCMs. The simulations used in this chapter are based on those from 17 CCMs that participated in the second round of a coordinated model intercomparison organized by the Chemistry-Climate Model Validation (CCMVal) Activity. This chapter builds on and extends the prognostic aspects of Chapter 7 of the 2007 Ozone Assessment with a primary focus on the role of ozone in affecting the future evolution of UV. While a brief discussion of the non-ozone factors affecting surface UV is included in this chapter, it primarily serves as a link to the UNEP (United Nations Environment Programme) Environm