Stephanie A. Vay

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[1] We have developed an automated observatory for measuring atmospheric column abundances of CO2 and O2 using near-infrared spectra of the Sun obtained with a high spectral resolution Fourier Transform Spectrometer (FTS). This is the first dedicated laboratory in a new network of ground-based observatories named the Total Carbon Column Observing Network.(More)
Climate models incorporate photosynthesis-climate feedbacks, yet we lack robust tools for large-scale assessments of these processes. Recent work suggests that carbonyl sulfide (COS), a trace gas consumed by plants, could provide a valuable constraint on photosynthesis. Here we analyze airborne observations of COS and carbon dioxide concentrations during(More)
[1] Satellite observations of carbon monoxide (CO) from the Measurements of Pollution in the Troposphere (MOPITT) instrument are combined with measurements from the Transport and Chemical Evolution Over the Pacific (TRACE-P) aircraft mission over the northwest Pacific and with a global three-dimensional chemical transport model (GEOSCHEM) to quantify Asian(More)
[1] We provide quantitative estimates for the spatial variability of CO2, crucial for assessing representativeness of observations. Spatial variability determines the mismatch between point observations and spatial averages simulated by models or observed from space-borne sensors. Such ‘‘representation errors’’ must be properly specified in determining the(More)
During October/November 1997, simultaneous observations of NO, HO2 and other species were obtained as part of the SONEX campaign in the upper troposphere. We use these observations, over the North Atlantic (40-60°N), to derive ozone production rates, P(O3), and to examine the relationship between P(O3) and the concentrations of NOx (= NO + NO2) and HOx (=(More)
[1] A NASA DC‐8 research aircraft penetrated tropospheric gas and aerosol plumes sourced from active volcanoes in Ecuador and Colombia during the Tropical Composition, Cloud and Climate Coupling (TC) mission in July–August 2007. The likely source volcanoes were Tungurahua (Ecuador) and Nevado del Huila (Colombia). The TC data provide rare insight into the(More)
We present a statistical representation of the aggregate effects of deep convection on the chemistry and dynamics of the upper troposphere (UT) based on direct aircraft observations of the chemical composition of the UT over the eastern United States and Canada during summer. These measurements provide unique observational constraints on the chemistry(More)
[1] Observed correlations between atmospheric concentrations of CO2 and CO represent potentially powerful information for improving CO2 surface flux estimates through coupled CO2-CO inverse analyses. We explore the value of these correlations in improving estimates of regional CO2 fluxes in east Asia by using aircraft observations of CO2 and CO from the(More)
We examine concurrent measurements of CN (size > 8 nm), NO, and NOy in the upper troposphere over the North Atlantic during the SONEX Experiment (Oct.-Nov., 1997). High CN and NOy observations are attributed largely to the enhancement in convective outflow. Using the ratio of NO/NOy as a chemical clock, we estimate that dilution of convective high-CN plumes(More)
[1] NOy (total reactive nitrogen) contained in ice particles was measured on board the NASA DC-8 aircraft in the Arctic in January and March 2000. During some of the flights, the DC-8 encountered widespread cirrus clouds. Large quantities of ice particles were observed at 8–12 km and particulate NOy showed large increases. The data indicate that the amount(More)