Southern California Air Quality Study: Tunable Diode Laser Absorption Spectrometer Measurements of HN03 at the Claremont 'A' Site

摘要

The tunable diode laser absorption spectrometer was used during the Southern California Air Quality Study to continuously measure the concentration of gas-phase nitric acid at Claremont, California. The measurements were made from June 15 through July 24, 1987. The detection limit was less than 0.1 ppbv for 1 minute averaging times. The data are presented in 1-minute, 15-minute, and 1-hour averages. Data recovery was better than 90 percent. The diurnal behavior of nitric acid was quite regular. The maximum concentrations occurred between 1200 and 1800 each day. The daily maximum varied considerably during the study from a low of 5 ppbv on July 21 to a high of 24 ppbv on June 25. Nighttime minima occured between 2200 and 0600 and were generally in the range 0.5 to 1 ppbv.