Are national HFC emissions reports suitable for global policy negotiation?
Lead Research Organisation:
University of Bristol
Department Name: Chemistry
Abstract
Negotiations are underway to determine whether the use of hydrofluorocarbons (HFCs) should be regulated under the Montreal Protocol, the international treaty that is designed to protect the stratospheric ozone layer. Whilst HFCs do not deplete stratospheric ozone, they are potent greenhouse gases (GHG), with global warming potentials hundreds to thousands of times that of carbon dioxide. Therefore, proponents of the proposed amendments to the Protocol argue that, because their rapid growth in the atmosphere is a direct result of the global phase-down of ozone depleting substances, for which HFCs are replacements, their resulting impact on global climate should now be regulated under the same framework. A major limitation of the on-going discussions is that emissions of HFCs are very poorly constrained at present, with more than 60% of the global emissions, as determined using atmospheric measurements, being un-reported in 2012. This could be due to poor reporting practices, and/or the incomplete nature of global emissions reports under the United Nations Framework Convention on Climate Change (UNFCCC), in which only a subset of countries are required to report their emissions in detail. Recent estimates of the emissions of HFCs and other synthetic GHGs derived from atmospheric measurements indicate that both factors are likely to contribute. However, a comprehensive evaluation of such "top-down" emissions estimates for the major reporting countries has not yet been carried out. Furthermore, we argue that the uncertainty quantification methods in the "inverse" modelling frameworks that are used to derive emissions of HFCs (and all other GHGs) must be dramatically improved if they are to be robust and relevant to policy makers.
This proposal aims to develop new methods for estimating national GHG emissions using atmospheric observations and chemical transport models. In particular, we will pioneer the use of hierarchical Bayesian modelling and Gaussian process emulation. These techniques will allow us, for the first time, to explicitly include the influence of some critical uncertainties in the atmospheric modelling process on "top-down" emissions estimates. This will allow us to estimate national emissions of the major HFCs with a more complete estimate of the uncertainty than has previously been possible. We will examine in detail the differences between these emissions estimates and the national inventories, and determine critically whether the current reports submitted to the UNFCCC are appropriate for informing the debate on the future of the Montreal Protocol.
This proposal aims to develop new methods for estimating national GHG emissions using atmospheric observations and chemical transport models. In particular, we will pioneer the use of hierarchical Bayesian modelling and Gaussian process emulation. These techniques will allow us, for the first time, to explicitly include the influence of some critical uncertainties in the atmospheric modelling process on "top-down" emissions estimates. This will allow us to estimate national emissions of the major HFCs with a more complete estimate of the uncertainty than has previously been possible. We will examine in detail the differences between these emissions estimates and the national inventories, and determine critically whether the current reports submitted to the UNFCCC are appropriate for informing the debate on the future of the Montreal Protocol.
Planned Impact
Emissions of hydrofluorocarbons (HFCs) are the subject of intense interest at present, due to on-going negotiations that aim to decide whether their use should be limited under the Montreal Protocol due to their potential to contribute significantly to global warming. Furthermore, there are growing concerns that estimates of the emissions of these substances, which are reported to the United Nations Framework Convention on Climate Change (UNFCCC) by "developed" countries, may be subject to inaccuracies or omissions. Therefore, the impacts of this proposal are targeted towards on researchers and agencies responsible for estimating HFC emissions, climate scientists and the general public, with the central aim of improving the information available for policy negotiation.
This proposal aims to quantify HFC emissions for the major reporting countries using atmospheric measurements, with a comprehensive evaluation of the uncertainty budget in such estimates. This information will be invaluable to agencies responsible for compiling national emissions inventories, as it will provide a robust, independent evaluation. It will also be useful to government departments and policy makers who are required to evaluate the success of emissions reduction schemes, and who must participate in international treaty negotiation, such as the on-going discussions surrounding the Montreal Protocol. In the UK, the primary beneficiary will be the Department for Energy and Climate Change (DECC), which is responsible for the UK's emissions reports. DECC have demonstrated their interest in this field, in particular, by funding a network of GHG monitoring sites in the UK, which will be used in this proposal.
In the UK and internationally, we will engage with a network of researchers who are responsible for estimating national GHG emissions. This particularly includes researchers in Switzerland and Australia, who, together with the UK, are the only countries to currently report "top-down" emissions estimates to the UNFCCC in addition to the more widely used "bottom-up" accounting methodologies. We will also engage with project partners in countries such as the USA and South Korea. Despite not producing detailed top-wodn emissions reports, these researchers, and the agencies that fund them, have a keen interest in developments that are being made in countries such as the UK, which will influence their future reporting plans.
It has recently been shown that HFCs could have a substantial impact on global climate in the coming decades. Therefore, HFC emissions must be of concern to the wider academic community interested in climate change. Furthermore, there is a high level of public concern regarding climate change and greenhouse gases.
A detailed engagement plan with these beneficiaries is outlined in the Pathways to Impact. The central strategy involves further strengthening the close ties that the team has with DECC and international researchers involved in the Advanced Global Atmospheric Gases Experiment (AGAGE). The outcomes of this research will be disseminated to these beneficiaries through workshops, meetings, and sharing of code and emissions estimates. We will engage with the wider research community and the general public through regular publications, attendance at general climate science conferences, and regular use of public outreach opportunities such as those organised through the University of Bristol's Cabot Institute.
This proposal aims to quantify HFC emissions for the major reporting countries using atmospheric measurements, with a comprehensive evaluation of the uncertainty budget in such estimates. This information will be invaluable to agencies responsible for compiling national emissions inventories, as it will provide a robust, independent evaluation. It will also be useful to government departments and policy makers who are required to evaluate the success of emissions reduction schemes, and who must participate in international treaty negotiation, such as the on-going discussions surrounding the Montreal Protocol. In the UK, the primary beneficiary will be the Department for Energy and Climate Change (DECC), which is responsible for the UK's emissions reports. DECC have demonstrated their interest in this field, in particular, by funding a network of GHG monitoring sites in the UK, which will be used in this proposal.
In the UK and internationally, we will engage with a network of researchers who are responsible for estimating national GHG emissions. This particularly includes researchers in Switzerland and Australia, who, together with the UK, are the only countries to currently report "top-down" emissions estimates to the UNFCCC in addition to the more widely used "bottom-up" accounting methodologies. We will also engage with project partners in countries such as the USA and South Korea. Despite not producing detailed top-wodn emissions reports, these researchers, and the agencies that fund them, have a keen interest in developments that are being made in countries such as the UK, which will influence their future reporting plans.
It has recently been shown that HFCs could have a substantial impact on global climate in the coming decades. Therefore, HFC emissions must be of concern to the wider academic community interested in climate change. Furthermore, there is a high level of public concern regarding climate change and greenhouse gases.
A detailed engagement plan with these beneficiaries is outlined in the Pathways to Impact. The central strategy involves further strengthening the close ties that the team has with DECC and international researchers involved in the Advanced Global Atmospheric Gases Experiment (AGAGE). The outcomes of this research will be disseminated to these beneficiaries through workshops, meetings, and sharing of code and emissions estimates. We will engage with the wider research community and the general public through regular publications, attendance at general climate science conferences, and regular use of public outreach opportunities such as those organised through the University of Bristol's Cabot Institute.
Organisations
- University of Bristol (Lead Research Organisation)
- Meteorological Office UK (Collaboration)
- National Aeronautics and Space Administration (NASA) (Collaboration)
- National Oceanic and Atmospheric Administration (Collaboration)
- University of Wollongong (Collaboration)
- Empa - Swiss Federal Laboratories for Materials Science and Technology (Collaboration)
- Massachusetts Institute of Technology (Collaboration, Project Partner)
- Commonwealth Scientific and Industrial Research Organisation (Collaboration)
- Kyungpook National University (Project Partner)
- Commonwealth Scientific and Industrial Research Organisation (Project Partner)
- National Institute for Environmental Studies (Project Partner)
- National Oceanic and Atmospheric Administration (Project Partner)
Publications

An M
(2021)
Rapid increase in dichloromethane emissions from China inferred through atmospheric observations.
in Nature communications

Brophy K
(2019)
Characterizing uncertainties in atmospheric inversions of fossil fuel CO<sub>2</sub> emissions in California
in Atmospheric Chemistry and Physics

Fang X
(2018)
Rapid increase in ozone-depleting chloroform emissions from China
in Nature Geoscience

Ganesan A
(2020)
Marine Nitrous Oxide Emissions From Three Eastern Boundary Upwelling Systems Inferred From Atmospheric Observations
in Geophysical Research Letters


Ganesan AL
(2017)
Atmospheric observations show accurate reporting and little growth in India's methane emissions.
in Nature communications

Kuyper B
(2019)
Atmospheric HCFC-22, HFC-125, and HFC-152a at Cape Point, South Africa.
in Environmental science & technology

Lickley M
(2021)
Quantifying the Imprints of Stratospheric Contributions to Interhemispheric Differences in Tropospheric CFC-11, CFC-12, and N 2 O Abundances
in Geophysical Research Letters

Lickley M
(2021)
Joint inference of CFC lifetimes and banks suggests previously unidentified emissions.
in Nature communications

Lunt M
(2016)
Estimation of trace gas fluxes with objectively determined basis functions using reversible-jump Markov chain Monte Carlo
in Geoscientific Model Development
Description | We have developed new methods for inferring hydrofluorocarbon (HFC) emissions using atmospheric observations. The methods have been used for a number of high-profile results including the recent identification of an increase in emissions of the banned ozone depleting substance, CFC-11, and the potent greenhouse gas HFC-23. |
Exploitation Route | We are creating a public code repository that will encapsulate the new developments that we are making in the inference of greenhouse gas emissions using atmospheric observations. This code can be used by any researcher. |
Sectors | Environment |
Description | The findings of our work on HFC emissions are being used in the World Meteorological Organisation Scientific Assessments of Ozone Depletion, 2018 and 2022. This assessment is mandated under the Montreal Protocol, providing Parties to the Protocol with updates on scientific advances in the field of ozone depletion. |
Sector | Environment |
Impact Types | Policy & public services |
Description | Lead authorship of World Meteorological Organisation Scientific Assessment of Ozone Depletion 2018 |
Geographic Reach | Multiple continents/international |
Policy Influence Type | Participation in a guidance/advisory committee |
URL | https://www.esrl.noaa.gov/csd/assessments/ozone/2018/ |
Description | SPARC Report on the Mystery of Carbon Tetrachloride |
Geographic Reach | Multiple continents/international |
Policy Influence Type | Participation in a guidance/advisory committee |
URL | https://doi.org/10.3929/ethz-a-010690647 |
Description | Met Office Newton Fund - Brazilian methane emissions |
Amount | £179,000 (GBP) |
Organisation | Meteorological Office UK |
Sector | Academic/University |
Country | United Kingdom |
Start | 03/2018 |
End | 03/2020 |
Description | NERC standard grant |
Amount | £800,000 (GBP) |
Funding ID | NE/R000921/1 |
Organisation | Natural Environment Research Council |
Sector | Public |
Country | United Kingdom |
Start | 01/2018 |
End | 12/2021 |
Description | PhD studentship with Edwards Ltd. |
Amount | £81,000 (GBP) |
Organisation | Edwards |
Sector | Private |
Country | United Kingdom |
Start | 09/2015 |
End | 03/2019 |
Description | Advanced Global Atmospheric Gases Experiment (AGAGE) |
Organisation | Commonwealth Scientific and Industrial Research Organisation |
Country | Australia |
Sector | Public |
PI Contribution | International programme to measure and model atmospheric trace gases |
Collaborator Contribution | Data provision. Model development. |
Impact | Several publications (e.g. Rigby et al., 2013; 2014). |
Start Year | 2008 |
Description | Advanced Global Atmospheric Gases Experiment (AGAGE) |
Organisation | Empa - Swiss Federal Laboratories for Materials Science and Technology |
Country | Switzerland |
Sector | Academic/University |
PI Contribution | International programme to measure and model atmospheric trace gases |
Collaborator Contribution | Data provision. Model development. |
Impact | Several publications (e.g. Rigby et al., 2013; 2014). |
Start Year | 2008 |
Description | Advanced Global Atmospheric Gases Experiment (AGAGE) |
Organisation | Massachusetts Institute of Technology |
Country | United States |
Sector | Academic/University |
PI Contribution | International programme to measure and model atmospheric trace gases |
Collaborator Contribution | Data provision. Model development. |
Impact | Several publications (e.g. Rigby et al., 2013; 2014). |
Start Year | 2008 |
Description | Met Office |
Organisation | Meteorological Office UK |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Expertise in inverse methods |
Collaborator Contribution | Exertise in atmospheric modelling |
Impact | Publications. |
Start Year | 2012 |
Description | NASA JPL |
Organisation | National Aeronautics and Space Administration (NASA) |
Department | Jet Propulsion Laboratory |
Country | United States |
Sector | Public |
PI Contribution | Statistical investigation of model parameterisations in OCO-2 retrieval code. |
Collaborator Contribution | Provision of data and model output. |
Impact | No outcomes yet |
Start Year | 2016 |
Description | National Oceanic and Atmospheric Administration (NOAA) Earth System Research Laboratory (ESRL) |
Organisation | National Oceanic And Atmospheric Administration |
Department | Earth System Research Laboratory (ESRL) |
Country | United States |
Sector | Public |
PI Contribution | Modelling of greenhouse gases. |
Collaborator Contribution | Provision of greenhouse gas data and expertise |
Impact | Several publications have resulted from this collaboration. |
Start Year | 2012 |
Description | University of Wollongong |
Organisation | University of Wollongong |
Country | Australia |
Sector | Academic/University |
PI Contribution | Model runs, data provision and processing, expertise in atmospheric modelling and statistics. |
Collaborator Contribution | Expertise in statistics |
Impact | Several publications, with further work in the pipeline. |
Start Year | 2013 |
Title | ACRG-Bristol/acrg: ACRG v0.2.0 |
Description | ACRG standardisation and inversion code v0.2.0 Added Ability to convert calibration scale in get_obs New "defaults" file that specifies inlets and instruments to use for particular time periods An obs.db SQLite database that specifies the location of all obs files and basic details about their contents (species, inlet, time range, etc.) notebooks directory for Jupyter notebooks notebooks/tutorials directory for notebook based tutorials a tmp directory to store random job script output files added a dev environment that includes spyder and a lighter environment that does not Changed get_single_site now returns a list of xarray datasets, one for each combination of inlet and site. If defaults are specified, the list will contain the default instruments and inlets for each period get_obs now returns a dictionary containing lists of datasets calibration scale and inlet are now attributes to obs datasets (e.g. ds.attrs["scale"]) fp_data_merge now works with new get_obs object The flux function will now look for species-total.nc named files first and then look for species.nc files. This will not be able to read both files. This can still accept an more explicit source such as co2-ff_*.nc as an alternative to this. arviz package version pinned to prevent conflict with pymc3 version |
Type Of Technology | Software |
Year Produced | 2022 |
Open Source License? | Yes |
Impact | This software is used to evaluate emissions of greenhouse gases for the UK and other countries. |
URL | https://zenodo.org/record/6834888 |
Title | mrghg/py12box: v0.2.2 |
Description | See documentation for 0.2.1. Updated packaging information |
Type Of Technology | Software |
Year Produced | 2022 |
Open Source License? | Yes |
Impact | This software is used to calculate global emissions of ozone depleting substances and greenhouse gases for the WMO Scientific Assessment of Ozone Depletion. |
URL | https://zenodo.org/record/6868589 |
Description | Carbon tetrachloride workshop: Solving the carbon tetrachloride mystery |
Form Of Engagement Activity | A formal working group, expert panel or dialogue |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Policymakers/politicians |
Results and Impact | A workshop to determine the global budget of carbon tetrachloride, a potent ozone depleting substance. A report of the workshop is in progress and will be disseminated to policy makers involved in the Montreal Protocol. |
Year(s) Of Engagement Activity | 2015,2016 |
URL | http://www.sparc-climate.org/news/news/news/2015/02/19/workshop-on-solving-the-mystery-of-carbon-tet... |
Description | WMO Integrated Greenhouse Gas Information System (IG3IS) workshop on Moroccan, South African and Brazilian emissions |
Form Of Engagement Activity | A formal working group, expert panel or dialogue |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Policymakers/politicians |
Results and Impact | Workshop with three countries to develop strategies for setting up greenhouse gas monitoring capabilities in each. |
Year(s) Of Engagement Activity | 2016,2017 |