Springtime chlorine dioxide and bromine monoxide measurements from a diode array spectrometer

A UV/visible diode array spectrometer was installed at Arrival Heights (93/94 seasons) for zenith skylight measurements of Chlorine Dioxide (OClO) and Bromine Monoxide (BrO) in two wavelength ranges, in the spring to see the perturbation of chlorine chemistry in the early spring with high levels of active chlorine and bromine being converted back to the reservoir (HCl) and active nitrogen levels recovering as the season progresses. Raw data is times and recorded spectro of scattered light. The derived data are column amounts of OClO and BrO. In the 06-97 season, the system was upgraded with a charge-coupled device (CCD) detector, a temperature controlled enclosure to improve stability and a modern operating system and controlling software.