I. Introduction

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I. Introduction I. INTRODUCTION DRAFT DOCUMENT (August 2014) Prepared by AC Le Gall (ICP M&M), To be reviewed by ICP M&M NFCs Updated by Anne Christine Le Gall, Chairwoman of the Task Force on Modelling and Mapping, from initial text by Till Spranger, Mapping Manual 2004 Please refer to this document as: CLRTAP, 2014. Introduction, Chapter 1 of Manual on methodologies and criteria for modelling and mapping critical loads and levels and air pollution effects, risks and trends. UNECE Convention on Long-range Transboundary Air Pollution; accessed on [date of consultation] on Web at www.icpmapping.org .” Chapter I – Introduction Page I - 3 TABLE OF CONTENT I. INTRODUCTION ........................................................................................................ 1 I.1 INTRODUCTION .................................................................................................... 5 I.2 THE CRITICAL LOAD AND LEVEL CONCEPT IN THE UNECE CONVENTION ON LONG-RANGE TRANSBOUNDARY AIR POLLUTION ................................... 6 I.3 AIMS AND ORGANIZATION OF THE MODELLING AND MAPPING PROGRAMME ...................................................................................................... 11 I.3.1 Division of Tasks within the Programme ..................................................... 11 I.3.2 Mandate for the Task Force of the ICP on Modelling and Mapping ............. 12 I.3.3 Mandate for the Coordination Centre for Effects ......................................... 12 I.3.4 Responsibilities of the National Focal Centres ............................................ 13 I.4 OBJECTIVES OF THE MANUAL ......................................................................... 13 I.5 STRUCTURE AND SCOPE OF THE MANUAL ................................................... 14 I.6 REFERENCES ..................................................................................................... 15 I.6.1 Historical references ................................................................................... 15 I.6.2 Gains model ............................................................................................... 15 I.6.3 Other bibliography ...................................................................................... 16 Chapter I – Introduction Page I - 5 I.1 INTRODUCTION The critical loads and levels concept is an effect- The general definition of critical levels based approach that has been used for defining is “the atmospheric concentrations of emission reductions aimed at protecting pollutants in the atmosphere above ecosystems and other receptors, such as which adverse effects on receptors, materials and human health. These indicators, such as human beings, plants, which may be used in a sustainability framework, ecosystems or materials, may occur are defined for specific combinations of pollutants, according to present knowledge” effects and receptors. Critical loads and levels (Nilsson and Grennfelt, 1988). Critical loads correspond to the pollutant provide a sustainable reference point against depositions on receptors. The which pollution levels can be compared. They can implications of these definitions in further be used for calculating emission ceilings terms of calculations and applications for individual countries with respect to acceptable within scientific and policy frameworks air pollution levels (e.g., defined reductions of are presented in Chapters III. 5 and critical load/level exceedances). VI. Critical loads and levels have been designed to support the setting of ambition levels and assess the efficiency of of air pollution reduction policies. Their development and their application in such a policy framework can be seen as an environmental design process, using the same models and methods as causal research but in a reverse sequence as shown in Figure I.1. Causal research Infrastructure Emission Deposition Ecosystem Effect Model 1 Model 2 Model 3 Model 4 Model -1 1 Model -1 2 Model -1 3 Model -1 4 Adaptation of Emission Critical Ecosystem No effect infrastructure limitations load requirement Environmental design Figure I.1 Environmental research vs. environmental design (adapted from Harald Sverdrup) Page I - 6 Chapter I – Introduction I.2 THE CRITICAL LOAD AND LEVEL CONCEPT IN THE UNECE CONVENTION ON LONG-RANGE TRANSBOUNDARY AIR POLLUTION During the 1970s, it was recognised that Bad Harzburg workshop the first trans-boundary air pollution has ecological discussions took place on the possible use and economic consequences (e.g. for the of critical level/loads maps for defining forest and fish industries) caused by areas at risk. It was foreseen that these acidifying air pollutants. In response to this, could play an important role in the the countries of the UN Economic development of air policy. Commission for Europe (UNECE) As a result of these workshops, in 1988, developed a legal, organisational and the Executive Body for the Convention scientific framework to deal with this approved the establishment of a problem. The UNECE Convention on Long- programme for mapping critical loads and range Transboundary Air Pollution levels (Task Force on Mapping) under the (LRTAP) was the first international legally Working Group for Effects (WGE) with binding instrument to deal with problems of Germany as the lead country air pollution on a broad regional basis (see (http://icpmapping.org/ ). In 1989 the http://www.unece.org/env/lrtap/ ). Signed in Executive Body welcomed the offer of the 1979, it entered into force in 1983. Netherlands to host a Coordination Centre 1 The Convention requires that its Parties for Effects (CCE) that was established at cooperate in research on the effects of RIVM in Bilthoven, The Netherlands sulphur compounds and other major air (http://wge-cce.org/ ). In 1999, the pollutants on human health and the Executive Body replaced the Task Force environment, including agriculture, forestry, on Mapping with the Task Force of the natural vegetation, aquatic ecosystems and International Cooperative Programme on materials (Article 7(d) of the Convention). Modelling and Mapping of Critical Loads The Convention also calls for the exchange and Levels and their Air Pollution Effects, of information on the physico-chemical and Risks and Trends (ICP M&M). In biological data relating to the effects of September 2009, France became the lead LRTAP and the extent of damage which country of this programme. these data indicate can be attributed to The mandates of the ICP M&M 2, the CCE LRTAP (Article 8(f) of the Convention). To and its National Focal Centres 3 are this end the Executive Body for the described further below. The Programme Convention established a Working Group position within the Convention is shown in on Effects (WGE) that is supported by a Figure I.2. number of International Cooperative Programmes (ICPs, cf. Figure I.2). In 1986, a work programme under the Nordic Council of Ministers agreed on scientific definitions of critical loads for sulphur and nitrogen (Nilsson, 1986). This stimulated the work under the Convention and in March 1988 two Convention workshops were held to further evaluate the critical levels and loads concept and to provide up-to-date figures. The Bad Harzburg (Germany) workshop dealt with 1 at the Netherlands Office for Environmental critical levels for direct effects of air Assessment (www.rivm.nl/cce) pollutants on forests, crops, materials and 2 established by the Executive Body in 1999 to natural vegetation, and the Skokloster replace the Task Force on Mapping, see Ch. (Sweden) workshop on critical loads for 1.3 sulphur and nitrogen compounds (Nilsson 3 and Grennfelt 1988). Furthermore, at the In 2013, 24 National Focal Centres are actively participating in the ICP M&M Chapter I – Introduction Page I - 7 EXECUTIVE BODY IMPLEMENTATION COMMITEE EECCA COORDINATING GROUP WORKING GROUP WORKING GROUP ON EMEP STEERING BODY ON EFFECTS STRATEGIES AND REVIEW TASK FORCE ON EMISSION ORESTS C ICP F OORDINATING INVENTORIES AND TASK FORCE ON REACTIVE PROGRAMME CENTRE PROJECTIONS NITROGEN CENTRE FOR EMISSION ICP I NTEGRATED INVENTORIES AND MONITORING P PROJECTIONS (CEIP) ROGRAMME CENTRE TASK FORCE ON HEAVY METALS TASK FORCE ON M ICP M ATERIALS AIN RESEARCH MEASUREMENTS AND CENTRE MODELLING CHEMICAL COORDINATING TASK FORCE ON CENTRE (CCC) TECHNICO -ECONOMIC ISSUES ICP V EGETATION PROGRAMME CENTRE METEOROLOGICAL SYNTHESIZING CENTRE ICP W ATERS WEST (MSC-W) PROGRAMME CENTRE METEOROLOGICAL SYNTHESIZING CENTRE ICP M ODELLING C EAST (MSC-E) AND MAPPING OORDINATION CENTRE FOR EFFECTS TASK FORCE ON INTEGRATED ASSESSMENT MODELLING TASK FORCE ON HUMAN HEALTH CENTRE FOR INTEGRATED ASSESSMENT MODELLING (CIAM) JOINT EXPERT GROUP ON DYNAMIC TASK FORCE ON HEMISPHERIC MODELLING TRANSPORT OF AIR POLLUTANTS Figure I.2: LRTAP organisation chart showing the position of the ICP M&M Task Force within the WGE. The Convention has been extended by for sulphur, i.e. avoid future exceedances. eight protocols which identify specific However, cutting sulphur dioxide emissions obligations or measures to be taken by to achieve deposition levels below critical Parties (cf. loads was not feasible for all ecosystems in http://www.unece.org/env/lrtap/status/lrtap_ Europe. Even so, the negotiations were s.html). The first substance-specific based on the assessment of environmental protocols were negotiated on the basis of effects and the protection of ecosystems as economic and technological information well as technical and economic (e.g. best available techniques). They set considerations. the same emission
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