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TF HTAP’s Mission

In December 2004, the Executive Body of the UNECE Convention on Long-range Transboundary Air Pollution (LRTAP Convention) established the Task Force on Hemispheric Transport of Air Pollution (TF HTAP).  In 2010, the Executive Body renewed and expanded the TF HTAP’s mandate to:

  1. Plan and conduct the technical work necessary to develop a fuller understanding of the hemispheric transport of air pollution across the northern hemisphere and the effects/impacts of potential mitigation options for consideration in the reviews of protocols to the Convention;

  2. Identify areas for coordination, as well as key issues for fostering complementary work and collaboration on the issue of particulate matter and its components, including black carbon and tropospheric ozone and its precursors by Parties under the Convention and by external bodies (including the Arctic Council/Arctic Monitoring and Assessment Programme (AMAP), the United Nations Environment Programme (UNEP) and the Intergovernmental Panel on Climate Change (IPCC));

  3. Cooperate closely with appropriate technical bodies under the Convention (e.g., the Expert Group on Techno-Economic Issues and the Task Force on Integrated Assessment Modelling) to estimate the extent to which these emissions and their impacts can be reduced, and regional climate co-benefits can be increased, by implementation of existing legislation and by implementation of specific control measures;

  4. Assess the impacts of emission-reduction opportunities in the UNECE region, as identified above, on regional and intercontinental transport of air pollution and their associated air quality, health, ecosystem and near-term climate effects; and begin to examine the impacts of complementary measures that might be taken in other regions where mitigation may prove more cost-effective;

  5. Identify the scientific and technical requirements (such as methods for emissions quantification, ambient monitoring and estimating global warming potential), as well as non-technical measures, needed for implementing options to reduce black carbon and ozone and their impacts in the region over time. This work should be done in collaboration with experts from subsidiary bodies under the Convention, including the Task Force on Integrated Assessment Modelling, the Task Force on Emission Inventories and Projections and the Task Force on Measurement and Modelling, as well as the programmes and centres of the Working Group on Effects;

  6. Develop a multi-year plan for carrying out further analyses on the tasks referred to in paragraphs (a) through (e), and report back to the EMEP Steering Body and Executive Body in 2011 for consideration in the 2012 workplan;

  7. Carry out such other tasks related to the above work as the Executive Body may assign to it in the annual workplan. [see Decision 2010/1 in ECE/EB.AIR/106/Add.1]


Based on this mandate, the TF HTAP adopted the following objectives to guide its current work:

  1. Deliver Policy Relevant Information to the LRTAP Convention, Other Multi-Lateral Forums, and National Governments By Addressing the Following Policy-Relevant Questions:

    1. In different continental or subcontinental regions of the world, what fraction of air pollution concentrations or deposition can be attributed to sources of contemporary anthropogenic emissions within the region as compared to extraregional, non-anthropogenic, or legacy sources of pollution?

    2. How do the various fractions of air pollution and deposition contribute to impacts on human health, ecosystems and climate change?

    3. How sensitive are regional pollution levels and related impacts to changes in the sources of the various fractions identified above?

    4. How will the various fractions and sensitivities defined above change as a result of expected air pollution abatement efforts or climate change?

    5. How do the availability, costs and impacts of additional emission abatement options compare across different regions?

  2. Improve Our Scientific Understanding of Air Pollution at the Global to Hemispheric Scale

  3. Build a Common Understanding by Engaging Experts Inside and Outside the LRTAP Convention

Leadership and Participation

The Task Force is chaired by Dr. Frank Dentener (European Community) and Dr. Terry Keating (United States). Participation in the Task Force is open to all interested experts. To date, experts from 38 countries around the world, including 14 from outside the UNECE have participated in TF HTAP activities.

National authorities (both inside and outside the UNECE region), as well as intergovernmental and accredited non-governmental organizations, are encouraged to nominate an individual expert as a national (or organizational) focal point. To nominate an expert as a focal point, please contact the Convention secretariat by e-mail at .