Periodic Reporting for period 2 - GREEN GODS (Global and Regional Emissions Estimates of Non-CO2 Greenhouse gases and Ozone Depleting Substances)
Reporting period: 2023-10-18 to 2024-10-17
The Montreal Protocol is widely regarded as the most successful international environmental treaty of all time, with substantial benefits to the stratospheric ozone layer and climate. However, recent work has shown that continued vigilance is needed. Emissions of the banned ozone depleting substance CFC-11 had increased from eastern China. The findings suggested the first major violation of the Montreal Protocol. Since publication, Chinese authorities have reported major enforcement activities to address the problem. However, the work highlighted several remaining scientific challenges that must be addressed to continue to support the Montreal Protocol and additionally, for climate, the Paris Agreement. Firstly, the magnitude of change in global emissions could not be reconciled with that inferred from eastern Asia, suggesting either that the global models could not accurately simulate year-to-year atmospheric trends, that the uncertainty estimates are insufficient, that there are as-yet-unidentified source regions of emissions elsewhere in the world, or some combination of each. Secondly, the work highlighted the critical need to accurately quantify emission magnitudes on global and regional (country to sub-continental) scales, not just for CFC-11, but for the more than 40 greenhouse gases (GHG) and ozone depleting substances (ODS) regulated under the Montreal Protocol and other agreements.
The project “GREEN GODS: Global and Regional Emissions Estimates of Non-CO2 Greenhouse gases and Ozone Depleting Substances” aims to use new models and statistical methodology to better quantify emissions of non-CO2 GHGs and ODS using atmospheric measurements and models of atmospheric transport.
This project has concluded with an increased knowledge of emissions of many greenhouse gases and ODSs, and an improved understanding of their drivers. A new, improved global model has been created, and made freely available, and is being implemented to quantify emissions of ODSs and greenhouse gases in a semi-operational manner. These emissions are anticipated to feed into the next Scientific Assessment of Ozone Depletion from the World Meteorological Organisation.
A particular highlight of the project has been work in determining that the emissions of many ODSs, for which production is banned for most uses under the Montreal Protocol, are increasing. This is thought to be primarily due to their use as feedstocks in the production of non-ODSs.
The project “GREEN GODS: Global and Regional Emissions Estimates of Non-CO2 Greenhouse gases and Ozone Depleting Substances” aims to use new models and statistical methodology to better quantify emissions of non-CO2 GHGs and ODS using atmospheric measurements and models of atmospheric transport.
This project has concluded with an increased knowledge of emissions of many greenhouse gases and ODSs, and an improved understanding of their drivers. A new, improved global model has been created, and made freely available, and is being implemented to quantify emissions of ODSs and greenhouse gases in a semi-operational manner. These emissions are anticipated to feed into the next Scientific Assessment of Ozone Depletion from the World Meteorological Organisation.
A particular highlight of the project has been work in determining that the emissions of many ODSs, for which production is banned for most uses under the Montreal Protocol, are increasing. This is thought to be primarily due to their use as feedstocks in the production of non-ODSs.
The project has so far produced results that have been published across 15 scientific publications in peer-reviewed journals.
Many of these publications have attracted attention in the mainstream media, across online news, print articles and on radio.
The results have been presented at a range of international and national conferences, and at 10 bespoke seminars and meetings.
A large focus of the results pertains to the quantification of emissions of ozone depleting substances, their changes over time and the drivers behind these.
Much of the attention has focussed on surprising turnarounds in emissions of substances that have been phased out, or are being phased out, under the Montreal Protocol.
In particular, feedstock use of ozone depleting substances has been an area of focus.
One of the main results of the project has been the creation of the MALTA two-dimensional transport model (https://github.com/lukewestern/malta(opens in new window)).
This model is open access and available for use for a wide range of applications, including the quantification of global emissions of greenhouse gases and ozone depleting substances.
Many of these publications have attracted attention in the mainstream media, across online news, print articles and on radio.
The results have been presented at a range of international and national conferences, and at 10 bespoke seminars and meetings.
A large focus of the results pertains to the quantification of emissions of ozone depleting substances, their changes over time and the drivers behind these.
Much of the attention has focussed on surprising turnarounds in emissions of substances that have been phased out, or are being phased out, under the Montreal Protocol.
In particular, feedstock use of ozone depleting substances has been an area of focus.
One of the main results of the project has been the creation of the MALTA two-dimensional transport model (https://github.com/lukewestern/malta(opens in new window)).
This model is open access and available for use for a wide range of applications, including the quantification of global emissions of greenhouse gases and ozone depleting substances.
It is anticipated that the methodology and results from this project will feed directly into reporting under the WMO Scientific Assessment of Ozone Depletion, and the subsequent studies which use of the information contained within the report (e.g. IPCC).
The MALTA model that has been developed under this project will likely be used semi-operationally for the reporting of global emissions of greenhouse gases and ozone-depleting substances and feature within future scientific studies.
The work on emissions from, the use of ozone depleting substances from their use as feedstocks will likely feed into policy decision making, such as the current Draft decision XXXVI/[B]: Feedstock uses of controlled substances under the Montreal Protocol.
The MALTA model that has been developed under this project will likely be used semi-operationally for the reporting of global emissions of greenhouse gases and ozone-depleting substances and feature within future scientific studies.
The work on emissions from, the use of ozone depleting substances from their use as feedstocks will likely feed into policy decision making, such as the current Draft decision XXXVI/[B]: Feedstock uses of controlled substances under the Montreal Protocol.