TY - JOUR
AU1 - Wert, Bryan P.
AU2 - Fried, Alan
AU3 - Drummond, James R.
AB - Rapid and accurate ambient measurements of the tropospheric trace gas formaldehyde (CH 2 O) have been made by the NCAR low altitude tunable diode laser absorption spectrometer on both aircraft and ground based platforms. Field sensitivities of 80 - 120 pptv in 1 minute (40 - 60 pptv in 5 min) were typical of the first aircraft version of the instrument, providing good resolution for studying formaldehyde's role in the oxidative mechanisms of the troposphere. Recently the instrument has been modified to provide simultaneous detection of a second tropospherically interesting molecule, hydrogen peroxide (H 2 O 2 ), as well as enhanced measurement precision and instrument stability. The optic assembly of the new Dual Channel Airborne Laser System (DCALS) has been designed to be more mechanically stable and better thermally conditioned. Other improvements include measures to mitigate optical noise, stabilize cell pressure, and minimize sample perturbation. Measurements of formaldehyde by DCALS at a ground site during the 1999 Southern Oxidants Study show improved sensitivities of 30 - 100 pptv in 1 minute, and much better long term instrument stability.
TI - Enhancement of a tunable diode laser tropospheric trace gas measurement system
JF - Proceedings of SPIE
DO - 10.1117/12.366441
DA - 1999-10-25
UR - https://www.deepdyve.com/lp/spie/enhancement-of-a-tunable-diode-laser-tropospheric-trace-gas-xAuTGPrqhU
SP - 100
EP - 108
VL - 3758
IS - 1
DP - DeepDyve
ER -