This dataset contains measurements of formaldehyde using laser induced fluorescence (LIF) made at the Institute of Atmospheric Physics land station (IAP), Beijing site during the winter and summer campaigns for the Atmospheric Pollution & Human Health in a Chinese Megacity (APHH) programme. Formaldehyde concentration measurements in pptv were made using the Leeds Formaldehyde instrument which uses off-resonance laser induced fluorescence at 353 nm to detect ambient formaldehyde. The instrument was calibrated at regular intervals during the campaign using a commercial permatube containing paraformaldehyde.

The Quantifying the Amazon Isoprene Budget: Reconciling Top-down versus Bottom-up Emission Estimates project produced a unique high resolution model (GEOS-Chem version v8-03-01 - with modifications) for the Amazon, which simulated isoprene emissions and atmospheric chemistry. A nested-grid version of the GEOS-Chem chemistry transport model, constrained by isoprene emissions from the Model of Emissions of Gases and Aerosols from Nature (MEGAN), and the Lund-Potsdam-Jena General Ecosystem Simulator (LPJ-GUESS) bottom-up inventories, was used to evaluate the impact that surface isoprene emissions have on formaldehyde (HCHO) air-mass factors (AMFs) and vertical column densities (VCDs) over tropical South America during 2006, as observed by the Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY) and Ozone Monitoring Instrument (OMI). Results of this project are presented in the following publication: Barkley, M. P., T. P. Kurosu, K. Chance, I. De Smedt, M. Van Roozendael, A. Arneth, D. Hagberg, and A. Guenther: Assessing sources of uncertainty in formaldehyde air mass factors over tropical South America: Implications for top-down isoprene emission estimates, J. Geophys. Res., 117, D13304, doi:10.1029/2011JD016827. 2012 and model outputs associated to this project are archived at CEDA. This was a NERC funded project.

The Quantifying the Amazon Isoprene Budget: Reconciling Top-down versus Bottom-up Emission Estimates project produced a unique high resolution model (GEOS-Chem version v8-03-01 - with modifications) for the Amazon, which simulated isoprene emissions and atmospheric chemistry. Formaldehyde (HCHO) vertical column measurements from the Scanning Imaging Absorption spectrometer for Atmospheric Cartography (SCIAMACHY) and Ozone Monitoring Instrument (OMI), and a nested-grid version of the GEOS-Chem chemistry transport model, are used to infer an ensemble of top-down isoprene emission estimates from tropical South America during 2006, using different model configurations and assumptions in the HCHO air-mass factor (AMF) calculation. Scenes affected by biomass burning are removed on a daily basis using fire count observations, and the local model sensitivity was used to identify locations where the impact of spatial smearing is small, though this comprises spatial coverage over the region Results of this project are presented in the following publication: Barkley, M. P., et al. (2013), Top-down isoprene emissions over tropical South America inferred from SCIAMACHY and OMI formaldehyde columns, J. Geophys. Res. Atmos., 118, 6849–6868, doi:10.1002/jgrd.5055 and model outputs associated to this project are archived at CEDA. This was a NERC funded project.