Vegetation across New York City and some densely populated adjoining areas has found that on many summer days, photosynthesis by trees and grasses absorbs all the carbon emissions produced by cars, trucks and buses, and then some. The surprising result, based on new hyper-local vegetation maps, points to the underappreciated importance of urban greenery in the carbon cycle. The study was just published in the journal Environmental Research Letters.
Our group measures methane and carbon dioxide concentrations at four locations around New York City. Two (at Lamont-Doherty Earth Observatory and Rutgers University) represent sites in the suburban areas and background measurements for air coming into the city, while the other two (at CUNY ASRC and at Mineola as part of the FROG-NY campaign) measure the city itself and the outflow from the city. We then use inverse modeling techniques to evaluate inventories for methane and carbon dioxide emissions across NYC.
Globally 70% of carbon dioxide (CO2) emissions are from urban areas. CO2 it is emitted from the combustion of carbon based fossil fuels in vehicles, power plants, generators, concrete plants, etc. CO2 is also is taken up by trees and respired from soils in the city.
Local Law 97 will require dramatic cuts in carbon emissions in NYC over the next few years. We will measure CO2 around the city to track those changes.
We joined in the NOAA funded project Fluxes of Reactive Organic Gases in New York (FROG-NY) to measure greenhouse gases at at tower in Mineola, NY during summer 2023. We measured CO2, CO, methane, ethane and N2O at two different heights.
We conducted a comparison of three methane/ethane gas analyzers at our CUNY ASRC field site in February 2022. This comparison tested the stability and precision of an Aerodyne Research Instruments Quantum Cascade Laser/Interband Cascade Laser (ARI SuperDUAL), an Aeris Technologies Ultra CH4/C2H6 (Aeris MIRA Ultra), and a Picarro G2210-i Cavity Ring Down Spectrometer (G2210-i). We recommend the Aerodyne SuperDUAL for its high precision, and the Aeris MIRA Ultra for its low cost and small size.