Approximately 70% of global greenhouse gas (GHG) emissions originate from urban areas, making accurate measurement and rigorous understanding of city-level emissions critically important for climate action. Quantifying these emissions is key to answering vital questions, such as tracking progress toward reduction targets and identifying the most successful mitigation efforts.
To help cities and stakeholders better tackle these challenges, a big group of ICOS Cities researchers have collaborated with the Integrated Global Greenhouse Gas Information System (IG3IS) and the World Meteorological Organization (WMO) to publish the 2025 edition of the Urban Emission Observation and Monitoring Good Research Practice Guidelines.
We did a Q&A with Lead Author and IG3IS Steering Committee Co-chair, Jocelyn Turnbull, to know more.
- What is the main purpose of these guidelines?
Cities and city governments are taking a leading role in mitigating greenhouse gas emissions. They need reliable, detailed emissions information to be able to take targeted action to mitigate their emissions. These guidelines aim to provide the pathway to establishing robust, reliable, detailed emissions information that goes beyond the current whole-city-total emission information that many cities are currently relying on.
- How will the guidelines be of use for cities?
These guidelines are the first step on the path to documentary standards, allowing cities and researchers alike to demonstrate that the emissions information they are providing is robust and accurate. These guidelines use atmospheric information to go beyond the data that can be gathered simply from activity data.
- Why do cities need these guidelines?
Every city has a different set of emission questions that they need answered, meaning that every city will need a slightly different set of measurements. These guidelines document all the available methods, and the pros and cons of each. This gives cities the chance to decide for themselves which methods are most suitable for their city, considering the size, geography and climate of the city, the emissions information that they need, and the resources and skills that they have at their disposal.
The second edition of the guidelines is a robust resource providing guidance for estimating urban GHG emissions, focusing primarily on the most significant drivers of anthropogenic climate change: carbon dioxide (CO2) and methane (CH4). The guidelines are structured in two parts: a concise guide for matching high-level emissions questions to appropriate methodologies, and detailed technical chapters on 31 distinct quantification approaches.
Access the updated edition here:
Urban Emission Observation and Monitoring Good Research Practice Guidelines
https://doi.org/10.59327/WMO/GAW/314
The Integrated Global Greenhouse Gas Information System (IG3IS) is an initiative under the Global Atmosphere Watch (GAW) Programme of the World Meteorological Organization (WMO). IG3IS works towards establishing good practices that enable the improved evaluation of greenhouse gas emissions and uptake on decision-relevant scales.