Technical Note: Low-Cost Arduino Based Open Air CO2 Flux Sensors For Environmental and Sociological Applications

CO2 flux between the terrestrial and atmospheric carbon pools have been used to understand myriad aspects of our world, from ecosystem productivity to anthropogenic carbon emissions. Satellite-based carbon flux data has more recently been used to measure inequalities in carbon appropriation among urban communities. However, current methods of collecting carbon flux data are generally limited by spatial resolution, temporal resolution, and/or cost. Our sensor array couples low-cost CO2, temperature, pressure, and humidity sensors with 3D anemometers, and collects data at a four second temporal resolution. The array also has remote deployment capability with the use of solar panels. Our goal is to use the disjunct eddy covariance (DEC) method to calculate CO2 flux across our deployments. Our current sensor deployments include (1) 33 sensors across every ward of Washington D.C. and (2) 25 sensors along a coastal gradient on the Eastern Shore of Virginia. In Washington D.C., we expect to understand carbon emission disparities across the city, with special attention paid to changes associated with the COVID-19 pandemic. On the Eastern Shore of Virginia, we expect to understand carbon flux changes across a coastal marsh-forest gradient with high levels of tree mortality. Our results will provide nuances in CO2 emission and flux patterns currently left unresolved with traditional CO2 flux methodology.