The scientific evidence that guides policy makers in ratifying and strengthening the original provisions of the Montreal Protocol is provided primarily by the periodic WMO/UNEP Scientific Assessments of Ozone Depletion and by other reports of the Scientific Assessment Panel (SAP), Technology and Economic Assessment Panel (TEAP) and the Environmental Effects Assessment Panel (EEAP). In addition, the Stratosphere-troposphere Processes And their Role in Climate (SPARC) project coordinates community assessment reports around specific issues which feed into the Ozone Assessments.

WP 6.1: Dissemination to Parties to the MP

Results from InHALE will be available for dissemination to the Parties via the 2026 and 2030 Ozone Assessments. However, as noted in WP 2, InHALE will also deliver annual updates on halocarbon budgets, providing valuable data with which to inform interim reports and working groups. Many of the InHALE PIs have served as regular authors of the Scientific Assessments or on the Scientific Steering Committee. This engagement in key MP bodies guarantees pull-through of InHALE results. The UK Department for Environment, Food and Rural Affairs (Defra) ODS/F-gas team will meet quarterly with the InHALE team to allow information exchange on issues of relevance to the Montreal Protocol. A member of this team within Defra will also sit on our Steering Committee, see Part C. If results emerge from InHALE that are judged to be important to communicate to the Parties, Defra staff will propose an appropriate side event at a Meeting of Parties.

Of relevance to the TEAP and EEAP, InHALE will provide new bank estimates, which will be rigorously compared to recent TEAP modelling efforts that began following the investigation into CFC-11. Furthermore, InHALE will address new environmental concerns regarding the replacement of HFCs by HFOs.

WP 6.2: SPARC report on Very Short Lived Substances

As outlined above, there has been intense recent research interest in VSLS. However, outside of the Ozone Assessments, there has yet to be a community effort to synthesise and communicate relevant findings and coordinate new developments internationally. To fill this gap, we have proposed a community activity on VSLS to the SPARC co-chairs. Such an activity would be highly relevant to the SPARC mission to connect tropospheric and stratospheric composition (see LoS from SPARC co-chairs). We will submit a full proposal if InHALE is funded and foresee opportunities for cross- disciplinary international collaboration on this topic.

WP 6.3: Engagement with IPCC and other climate assessments

InHALEs work on ERFs and indirect GWPs will have relevance to IPCC AR7, as will its research identifying areas where the climate impact of halocarbons is disproportionately large. Our team have served as authors, co-authors, and contributors on IPCC Assessments. The schedule for AR7 has not yet been released, but our team will likely contribute across working groups, sharing results from InHALE.

WP 6.4: Public engagement

We have a strong history of public dissemination of scientific developments related to halocarbons. In recent years, this has included interviews with prominent media outlets (e.g., the BBC, New York Times, etc.), press releases, and articles commissioned by outlets such as The Conversation. Through InHALE, we will also engage public audiences through the development of an interactive data dashboard, which shows recent global atmospheric halocarbon observations, and describes how the data are used to support the Montreal Protocol. This effort will build on recent developments from the NERC-funded OpenGHG project, which developed a data dashboard to showcasegreenhouse gas data collected in Glasgow during COP26.

WP 6.5: Engagement with industry

Engagement with industry is built into the design of InHALE through close integration of partners such as Honeywell, and key industry consultants. Throughout InHALE, we will meet with these partners on a regular basis to co-develop various aspects of the InHALE research. Industry partners and other key industry stakeholders will be invited to annual InHALE project meetings to present findings and steer the future direction of the project.