Relative Tropospheric Photolysis Rates of Acetaldehyde and Formaldehyde Isotopologues Measured at the European Photoreactor Facility

The photolysis rates of HCHO, DCDO, CH₃CHO, and CH₃CDO are studied by long-path FTIR spectroscopy in natural tropospheric conditions at the European Photoreactor Facility (EUPHORE) in Valencia, Spain. Average relative photolysis rates j_HCHO/j_DCDO = 3.15 ± 0.08 and j_CH3CHO/j_CH3CDO = 1.26 ± 0.03 are obtained from three days of experiments for each reaction in the period June 17 to July 7, 2006.