The Task Force on Hemispheric Transport of Air Pollution (TF HTAP) was created by the Convention on Long-range Transboundary Air Pollution (LRTAP Convention) in December 2004 to facilitate research to improve the understanding of the intercontinental transport of air pollutants across the Northern Hemisphere. Findings from TF HTAP’s work have been documented in a series of technical reports [Keating 2007; Dentener 2010; Pirrone 2010; Dutchak 2010; Keating 2010a], and more recently, a special issue of the journal Atmospheric Chemistry and Physics (ACP) [Dentener 2019].
TF HTAP is a scientific expert group, but its work and findings have important policy implications for the LRTAP Convention, as well as for other international efforts and national governments. The TF HTAP chairs have attempted to distill the policy-relevant findings and messages from the TF HTAP’s work at several times in the past. The HTAP 2010 comprehensive assessment was summarized in a question and answer format in Volume D of the report [Keating 2010a], in an executive summary [Keating 2010b], and in an informal note from the TF HTAP chairs to the Executive Body’s 28th session [Keating 2010c]. Findings from the ACP special issue have been summarized in an informal note from the TF HTAP chairs to the EMEP Steering Body [Keating 2020].
Distilling policy-relevant messages from scientific analyses is often quite challenging, especially where there is significant scientific uncertainty. Scientific answers are often carefully crafted to avoid overstating findings, but the nuances and caveats can lead to confusing language. Effective communication often requires more dialogue than can be achieved through a traditional report drafting and review process.
To facilitate more dialogue and effective communication between TF HTAP and policy audiences, particularly the LRTAP Convention’s Working Group on Strategies and Review (WGSR), we have created this online document. The document is organized around policy-relevant questions and the initial answers to the questions draw upon the HTAP 2010 assessment, the ACP 2019 special issue, and other related literature. We invite contributors to comment on and suggest revisions to both questions and answers. Through iterative drafting and dialogue, we hope to be able to refine the answers to be useful to policy makers as the answers also continue to evolve with new research and analysis, which in turn may be guided by the science-policy dialogue around this document.