91���˰涶��

The Paris Agreement entered into force in October 2016. The 195 cosignatories are now striving to meet its goals. With corporations adapting their sustainability plans to demonstrate how their operations are reducing emissions, the global carbon market will likely be worth one trillion dollars by the end of 2024.

But how good are the data being used to track net zero progress? How effective are the many various carbon offset projects? And, what emissions are really going into the atmosphere?  

Associate Professor Bryce Kelly from UNSW Sydney’s School of Biological, Earth & Environmental Sciences says few people appreciate that the carbon accounts used to track progress are mostly estimated using spreadsheets and productivity data.

“Much of the carbon accounting is done by financial accounting firms,” A/Prof. Kelly says. 

“We are making robust guesstimates of our net emissions when we really need to be measuring our true emissions and what is being stored in Earth’s carbon pools.”

He says due to the over-reliance on bottom-up carbon accounting methods, some corporations are currently not aware of the magnitude of their carbon liability risk—which can be worth tens of thousands to hundreds of millions of dollars, depending on the size of the corporation.

“The current bottom-up Intergovernmental Panel on Climate Change (IPCC) protocols are extremely useful for guiding net zero mitigation programs and Paris Agreement progress. But bottom-up carbon accounts need to be verified using top-down measurements,” he says.

“This means using greenhouse gas analysers that are transported within satellites, aircraft or cars.

“Even better would be establishing networks of continuous monitoring ground stations in key regions.”

“Ideally, measuring the rate of greenhouse gas emissions being emitted into the atmosphere from industrial facilities, mines and farms should be common practice—but unfortunately it is not”—A/Prof. Bryce Kelly

Challenges & opportunities

The importance of atmospheric observations for inventory verification came to light with the United Nations Environment Programme (UNEP) Methane Science Study in Queenland’s Surat Basin.

Aerial surveys revealed that methane emissions from the coal seam gas (CSG) fields in the region were much higher than previous reports— transforming not just the understanding of methane emissions, but their environmental impact.

“This project was the first in the world to verify the rate of greenhouse gas emissions from coal seam gas using airborne measurements and isotope studies,” A/Prof. Kelly says.

But at the beginning of the study, bottom-up carbon accounting methods for quantifying emissions from coal seam gas were evolving.

As a key researcher for the project, A/Prof. Kelly says there is now  between the results of the atmospheric observation and the Australian Government bottom-up methods used to annually estimate emissions from coal seam gas.

“Our focus was to measure methane accurately,” he says.

At the , he presented the results of the study as an example of best practice inventory verification. The work is now cited in the  to the United Nations Framework Convention on Climate Change and the Paris Agreement. It has also been cited in many policy documents by the United Nations, UNEP, Food and Agriculture Organization of the United Nations, IPCC, World Meteorological Organization, UK Government, Australian Government, Asian Development Bank, the Organisation for Economic Co-operation and Development (OECD) and more.

“This extensive impact highlights the value of applied research that is aligned with the objectives of the Paris Agreement—and also the Sustainable Development Goals (SDGs).”—A/Prof. Bryce Kelly

Future focused

There is also tremendous educational value in the applied research. In 2023, UNSW Sydney honours student Hannah Beaton contributed to an urban fugitive methane mapping project for the NSW Environmental Protection Agency (EPA). Her project helped . The EPA says they have since been "working with some of the facilities to improve their gas management systems and to strengthen environmental performance requirements." This is key in achieving the objectives of the .

Measuring and modelling the rate of emissions from regions and facilitates requires specialists. Researchers from the Schools of Biological, Earth and Environmental Sciences,��Aviation�����Ի���Mathematics and Statistics hope to change this situation.

As a collaborative team, the UNSW Sydney researchers—A/Prof. Kelly, Hannah Beaton, Dr Stephen Harris, Professor Jason Middleton, Peter Mumford and Professor Scott Sisson—are developing workflows that can be adopted by industry and government.

“This will help them achieve their carbon management goals,” A/Prof. Kelly says.

The research and workflow development is in collaboration with the , and the  (IMEO) teams.

“We are an international team providing real solutions for mapping and mitigating greenhouse gas emissions and verifying true emission reduction success stories,” A/Prof. Kelly says.