Comparison of Multiple Approaches for Quantifying Winter Greenhouse Gas Emissions in New York City Based on Aircraft Measurements

Abstract:

To effectively address the unprecedented acceleration of climate change, cities across the U.S. are leading efforts to reduce greenhouse gas emissions. Coherent, aggressive, and lasting mitigation policies in controlling carbon emissions are beginning to be adopted to help strengthen climate resilience across different sectors. In particular, New York City has recently passed the Climate Mobilization Act with the purpose of reducing building emissions, which contribute to nearly three-quarters of all citywide emissions, by levying significant fees for non-compliant owners. The resulting changes in emissions must be monitored through measurable, reportable, and verifiable means to evaluate the effectiveness of current climate legislations. As a part of this effort, we are performing a long-term series of aircraft measurements downwind of New York City, during the non-growing seasons. In this presentation, we compare three different top-down approaches to emission estimation: mass balance technique, inventory scaling, and inverse modeling. We tested different background definitions, mass balance representative area, and measurement uncertainties for 9 flights between 2018 and 2020 to compare between the different approaches and bottom up emission products, as well as to estimate the variability of the results.