INSTRUMENTATION FOR CHEMICAL-SPECIES MEASUREMENTS IN THE TROPOSPHERE AND STRATOSPHERE

In particular, several classes of measurement challenges demand further effort. These include: 1) fast response, real time measurement of key oxidative radical species, most importantly OH, but also HO2, RO2, NO3 and various halogen oxide species; 2) sensitive, real time capability for key reservoir species, including HNO3, H2O2, ClONO3, BrONO3, HO2NO2, and organic nitrates; 3) more sensitive, real time techniques for SO2 and reduced sulfur gases; 4) automated, highly precise techniques to determine source gas trends for CH4, N2O, and a wide variety of halocarbons; 5) more responsive and comprehensive methods to routinely measure concentrations of key classes of volatile organic compounds, and 6) significant improvements in determing size distributions, number densities and chemical compositions of aerosols and cloud droplets. -from Author