Strategies for Emissions Inventory, Scope 3, Air Pollution, and GHG Management

Over the past 15 years, I have dedicated my career to developing emissions inventories for both air pollution and greenhouse gas (GHG) emissions. Through this journey, I have learned that emissions inventories are not just technical tools—they are powerful instruments that, when used correctly, offer cost-effective alternatives to expensive air pollution monitoring, policy efficiency, solution design, hotspot identification, and much more. If your goal is to achieve zero carbon emissions, conduct thorough policy evaluations, or set ambitious environmental goals, emissions inventories are unparalleled in their utility.

For many people, emissions inventory development can either seem incredibly straightforward or overwhelmingly complex. This perception largely depends on the context and the approach one takes. Some people do a top-down approach, which might involve using country-scale data, then downscaling it using ratios or proportions to fit a specific entity or area. This can make the process seem relatively simple. Conversely, for other people who do a bottom-up approach that uses detailed activity data for specific sectors, it can appear much more challenging. When these two groups of people talk, these contrasting views often lead to interesting discussions among professionals in the field.

One major challenge I’ve noticed in emissions inventory development is the understanding of data. People often get excited about big models and datasets provided by third parties, but even simple Excel sheets with manually searched data can yield impressive results. Even if you are using these data, always look for the root data sources. It's crucial to be aware of the major datasets that are openly available; this could be government data or data available on platforms like Amazon. Always look for root data sources, as this helps in understanding the data's quality and ensures that investments in data are worthwhile.

Consider the discussion around Scope 3 emissions. Many people find this difficult. My perspective is that while it is challenging, it can be simplified depending on how you approach it. Factors such as the time frame, objectives, and specific context all play a significant role in determining the complexity. If you have a clear understanding of datasets and their granularity variables, you can get datasets which are sometimes better than expensive data you are purchasing.

In my experience, some data that might initially seem useless can actually be quite valuable. As an emissions inventory professional, it’s important to be aware of every government and survey data source. These sources can sometimes provide accuracy levels comparable to field data. It all depends on how you view and utilize the data. For example, in one instance, we needed detailed age profiling of vehicles and their technologies for a city. We achieved this using census and expenditure data. It might sound improbable, but it is indeed possible. By using consumer expenditure data, we were even able to estimate restaurant patronage patterns and identify major consumer groups.

During training and workshops, I've often observed that we spend a significant amount of time understanding software and datasets provided by other entities. However, I believe that separate sessions focused solely on understanding data, variables, and related aspects would be more beneficial. This would reduce difficulties in developing better activity analyses and associated emissions.

Before developing any datasets, it is essential to set proper goals. These goals should go beyond merely developing an emissions inventory; they should consider granularity, resolution, and both temporal and spatial aspects.

Lastly, leveraging AI to understand data can be incredibly useful. It helps in interpreting data in layman’s terms, making it accessible to everyone, from new employees to seasoned experts. This approach not only enhances comprehension but also ensures that all team members, regardless of their experience level, can contribute effectively to the project.

In conclusion, emissions inventories are invaluable tools that, when used correctly, can transform environmental policy and practice. By understanding and utilizing data effectively, we can overcome challenges and achieve significant progress in air pollution monitoring, policy efficiency, and beyond.

Ajay Nagpure