Quantifying the impact of biogenic and anthropogenic fluxes on the atmospheric composition of the New York City Metro Area

Urban areas comprise only 3% of Earth?s land area, but account for ?70% of global fossil fuel derived carbon dioxide (CO2) emissions. Many cities have pledged to
adopt ambitious climate policies but our knowledge of urban scale total CO2 emissions is highly uncertain. Quantifying CO2 emissions from urban areas now will provide a baseline against which we can assess the effectiveness of policies as they are implemented. Our overarching goal is to understand the link between the CO2 and ozone (O3) cycles by improving our knowledge of the fluxes from anthropogenic and biogenic sources in urban areas. Our proposed observations in the New York Metropolitan Area (NYMA), the most populous urban center in the United States, will allow us to quantify the biogenic contribution of the CO2 and VOC budgets on daily, seasonal and interannual time scales using field observations and model estimates. We will quantify the atmospheric loading due to anthropogenic CO2 and O3 precursors over the NYMA using a range of existing inventories. Until we fully understand the role of the biosphere at mid-latitudes as a summertime carbon sink and source of reactive carbon precursors to air pollution, our confidence will remain limited in projections of the impacts of a warming climate and increased urbanization on atmospheric composition, including urban air quality and public health.
We will couple a year-round CO2 observation network around the New York Metro Area with targeted field studies to quantify fluxes of CO2 and VOCs and improve
our understanding of the processes driving spatiotemporal variability in this region. We expect the insights gained through our project will apply in some other mid-latitude urban settings. We will use a range of modeling approaches to calculate the impact of these processes on the composition and chemistry of the urban atmosphere. By advancing knowledge of both anthropogenic and biogenic carbon fluxes, we directly address the NOAA Climate goal of ?more comprehensive knowledge of greenhouse gases?. Our proposed work directly addresses a number of the NOAA FY2020 AC4 competition foci by using a multi-species approach to understanding the urban environment, undertaking research with the potential to inform mitigation strategies, especially with regard to co-benefits for air pollution and greenhouse gas reduction and investigation of the evolution of urban air composition in a warming climate. The call encourages more observations and coordination and information exchange among scientists measuring different aspects of the urban atmosphere, which we will accomplish by developing an observation network, conducting targeted field studies and modeling from carbon and air quality perspectives. Our team includes expertise in measuring greenhouse gases and reactive chemical species in the atmosphere, modeling and data analysis of atmospheric chemistry and composition, urban ecology, and ecophysiology.