With numerous governments, cities, and organisations declaring climate emergencies and net-zero emissions targets, greenhouse gases (GHGs) are now the focus of international geopolitics and UK domestic policies. Furthermore, with the recent identification of violations of the Montreal Protocol, ozone depleting substances (ODS), are receiving renewed attention. It is therefore critically important to be able to analyse GHG and ODS emissions trends, examine spatial patterns, estimate future trajectories, and explore mitigation options in an open, transparent and publicly accessible way. Our proposed project will enable this, using state-of-the-art computing technology to create a platform, "OpenGHG".

The estimation of GHG and ODS emissions requires close collaboration between a diverse group of scientists and stakeholders: "bottom-up" methods rely on statistical information collected by governments and industries, combined with scientific studies of the emissions intensity of particular activities, or the development of computer models that describe how human or natural processes produce or absorb GHGs. Complementary "top-down" techniques rely on instruments developed by spectroscopists and analytical chemists, the data from which are analysed along with outputs from meteorological models using advanced statistical methods.

The data that is being generated by these diverse research and stakeholder communities is growing rapidly. However, the development of computational tools to help researchers aggregate data from such a wide range of sources and carry out and share analyses has not kept pace. Furthermore, given the sensitive nature of, for example, the inference of national GHG or ODS emissions, these communities must urgently take steps to make their analyses more transparent and reproducible.

OpenGHG meets these needs, by providing an open, cloud-based, platform for researchers to share data and analysis methods and publish workflows. Furthermore, we have co-designed with our stakeholders, a range of tools that will facilitate the sharing of research outputs with governments, private companies and the public. The OpenGHG platform will:
- Continuously incorporate and standardise up to date GHG and ODS measurements, bottom-up emission estimates, and a range of ancillary information related to GHG and ODS emissions. This data will be pulled automatically, or on demand, from a range of public archives, or pushed to the platform by data providers seeking to analyse or share their own data
- Provide a wide range of analysis options, including the ability to design, publish and share custom workflows
- Allow production of new top-down and bottom-up emissions estimates by accessing pre-existing and newly developed models and methods incorporated into the platform
- Provide users with lower levels of computational expertise an easy-to-use interface for the most useful data analysis and visualisation. This will include comparisons of top-down and bottom-up estimates of emissions from different sectors of the economy, and potential future warming from different emissions scenarios.

Potential Impact:
The credibility and effectiveness of the UK Climate Change Act (2008) and the Paris Agreement requires transparent and accurate reporting of greenhouse gas (GHG) emissions. Furthermore, our recent work has shown that the continued success of the Montreal Protocol (MP) will require close collaboration between policymakers and researchers studying changes in ozone depleting substances (ODS). OpenGHG will meet these needs in the following ways.

National GHG emissions reporting:

Our work will benefit stakeholders involved in the national GHG emissions inventory process, both in the UK and internationally. Our key stakeholders in this area are the Department of Business, Energy and Industrial Strategy (BEIS) and Defra, who are responsible for delivering the GHG inventory under the United Nations Framework Convention on Climate Change (UNFCCC). BEIS have specifically requested further "verification research and improved data and methodology for inventory compilation". This work will bring together a range of stakeholders involved in the UK inventory: Ricardo Energy and Environment, contractors with overall responsibility for the national inventory, The UK Met Office, who contribute atmospheric-data-based estimates for the UK's National Inventory Report (making the UK world-leading in this regard), and the new BEIS-funded, CEH-led UK Emissions Modelling System. Internationally, we will work with organisations interested in developing emissions evaluation systems, via the World Meteorological Organisation (WMO) Integrated Greenhouse Gas Information System (IG3IS).

OpenGHG will benefit these groups in a number of ways. Firstly, by providing an open platform for analysing and publishing GHG datasets, best practices can be more readily shared nationally and internationally, and trust in the system can be improved. Furthermore, the removal of barriers between researchers and stakeholders inevitably leads to an enhancement in the accuracy of the inventory. Secondly, the OpenGHG platform will provide stakeholders with a suite of interactive tools to allow them to better understand GHG data and interrogate reasons for differences between methods. This will help decision-makers plan for the most efficient climate mitigation actions based on the best available data.

The Montreal Protocol:

Recent high-profile examples from our team have shown that the continued success of the MP will require prompt, effective and accurate dissemination of scientific findings to its Parties. We will work closely with Defra's Stratospheric Ozone and Fluorinated Gas Team, to ensure that our research is represented at regular meetings of the MP. Via the WMO and UN Environment, we will engage with Parties to the MP more broadly.

We anticipate that OpenGHG will primarily benefit the Parties to the MP by streamlining the process of sharing and publishing ODS data and analysis. Analyses published on the platform can be most effectively disseminated to the Parties via the quadrennial WMO Scientific Assessments of Ozone Depletion, and other UN Environment-commissioned reports, which our team have been integral to (e.g., Rigby and Harris have served as lead authors on numerous assessments and reports).

The media and public:

Our team have extensive media experience and receive regular requests for materials to help journalists communicate GHG and ODS data science. The OpenGHG platform will include public-facing web tools that the media can link to, to interact with data and analyses developed on the platform.

Cloud providers and communities interested in cloud-based research:

We have close links with all the major cloud providers, for whom, our work will serve as a valuable case study that will enable them to better map their service offerings to the needs of researchers. Similarly, our experience in using commercial and public cloud platforms will be valuable to the rapidly increasing number of groups who wish to use the cloud for research.