 |
| Titel |
Evaluation of the airborne quantum cascade laser spectrometer (QCLS) measurements of the carbon and greenhouse gas suite – CO2, CH4, N2O, and CO – during the CalNex and HIPPO campaigns |
| VerfasserIn |
G. W. Santoni, B. C. Daube, E. A. Kort, R. Jiménez, S. Park, J. V. Pittman, E. Gottlieb, B. Xiang, M. S. Zahniser, D. D. Nelson, J. B. McManus, J. Peischl, T. B. Ryerson, J. S. Holloway, A. E. Andrews, C. Sweeney, B. Hall, E. J. Hintsa, F. L. Moore, J. W. Elkins, D. F. Hurst, B. B. Stephens, J. Bent, S. C. Wofsy |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1867-1381
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Measurement Techniques ; 7, no. 6 ; Nr. 7, no. 6 (2014-06-02), S.1509-1526 |
| Datensatznummer |
250115805
|
| Publikation (Nr.) |
 copernicus.org/amt-7-1509-2014.pdf |
|
|
|
|
|
| Zusammenfassung |
| We present an evaluation of aircraft observations of the carbon and
greenhouse gases CO2, CH4, N2O, and CO using a
direct-absorption pulsed quantum cascade laser spectrometer (QCLS) operated
during the HIPPO and CalNex airborne experiments. The QCLS made continuous
1 Hz measurements with 1σ Allan precisions of 20, 0.5, 0.09, and
0.15 ppb for CO2, CH4, N2O, and CO, respectively, over
> 500 flight hours on 79 research flights. The QCLS
measurements are compared to two vacuum ultraviolet (VUV) CO instruments
(CalNex and HIPPO), a cavity ring-down spectrometer (CRDS) measuring CO2
and CH4 (CalNex), two broadband non-dispersive infrared
(NDIR) spectrometers measuring CO2 (HIPPO), two onboard gas chromatographs measuring a
variety of chemical species including CH4, N2O, and CO (HIPPO), and
various flask-based measurements of all four species. QCLS measurements are
tied to NOAA and WMO standards using an in-flight calibration system, and mean
differences when compared to NOAA CCG flask data over the 59 HIPPO research
flights were 100, 1, 1, and 2 ppb for CO2, CH4, N2O, and CO,
respectively. The details of the end-to-end calibration procedures and the
data quality assurance and quality control (QA/QC) are presented.
Specifically, we discuss our practices for the traceability of standards
given uncertainties in calibration cylinders, isotopic and surface effects
for the long-lived greenhouse gas tracers, interpolation techniques for
in-flight calibrations, and the effects of instrument linearity on retrieved
mole fractions. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|