% IMPORTANT: The following is UTF-8 encoded. This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.
@ARTICLE{Schlosser:6107,
author = {Schlosser, E. and Brauers, T. and Dorn, H.-P. and Fuchs, H.
and Häseler, R. and Hofzumahaus, A. and Holland, F. and
Wahner, A. and Kanaya, Y. and Kajii, Y. and Miyamoto, K. and
Nishida, S. and Watanabe, K. and Yoshino, A. and Kubistin,
D. and Martinez, M. and Rudolf, N. and Harder, H. and
Berresheim, H. and Elste, T. and Plass-Dülmer, C. and
Stange, G. and Schurath, U.},
title = {{T}echnical {N}ote: {F}ormal blind intercomparison of {OH}
measurements: results from the international campaign
{HO}x{C}omp},
journal = {Atmospheric chemistry and physics},
volume = {9},
issn = {1680-7316},
address = {Katlenburg-Lindau},
publisher = {EGU},
reportid = {PreJuSER-6107},
pages = {7923 - 7948},
year = {2009},
note = {This work was supported by the EU FP-6 program EUROCHAMP
(grant no. RII3-CT-2004-505968) and ACCENT (Priority
1.1.6.3. Global Change and Ecosystems, grant no.
GOCE-CT-2004-505337).We thank F. Rohrer, R. Tillmann, and B.
Bohn for helpful discussions and supporting measurements,
and F. J. Johnen for assistance with the experiments.},
abstract = {Hydroxyl radicals (OH) are the major oxidizing species in
the troposphere. Because of their central importance,
absolute measurements of their concentrations are needed to
validate chemical mechanisms of atmospheric models. The
extremely low and highly variable concentrations in the
troposphere, however, make measurements of OH difficult.
Three techniques are currently used worldwide for
tropospheric observations of OH after about 30 years of
technical developments: Differential Optical Laser
Absorption Spectroscopy (DOAS), Laser-Induced Fluorescence
Spectroscopy (LIF), and Chemical Ionisation Mass
Spectrometry (CIMS). Even though many measurement campaigns
with OH data were published, the question of accuracy and
precision is still under discussion.Here, we report results
of the first formal, blind intercomparison of these
techniques. Six OH instruments (4 LIF, 1 CIMS, 1 DOAS)
participated successfully in the ground-based, international
HOxComp campaign carried out in Julich, Germany, in summer
2005. Comparisons were performed for three days in ambient
air (3 LIF, 1 CIMS) and for six days in the atmosphere
simulation chamber SAPHIR (3 LIF, 1 DOAS). All instruments
were found to measure tropospheric OH concentrations with
high sensitivity and good time resolution. The pairwise
correlations between different data sets were linear and
yielded high correlation coefficients (r(2)=0.75-0.96).
Excellent absolute agreement was observed for the
instruments at the SAPHIR chamber, yielding slopes between
1.01 and 1.13 in the linear regressions. In ambient air, the
slopes deviated from unity by factors of 1.06 to 1.69, which
can partly be explained by the stated instrumental
accuracies. In addition, sampling inhomogeneities and
calibration problems have apparently contributed to the
discrepancies. The absolute intercepts of the linear
regressions did not exceed 0.6x106 cm(-3), mostly being
insignificant and of minor importance for daytime
observations of OH. No relevant interferences with respect
to ozone, water vapour, NOx and peroxy radicals could be
detected. The HOxComp campaign has demonstrated that OH can
be measured reasonably well by current instruments, but also
that there is still room for improvement of calibrations.},
keywords = {J (WoSType)},
cin = {ICG-2},
ddc = {550},
cid = {I:(DE-Juel1)VDB791},
pnm = {Atmosphäre und Klima},
pid = {G:(DE-Juel1)FUEK406},
shelfmark = {Meteorology $\&$ Atmospheric Sciences},
typ = {PUB:(DE-HGF)16},
UT = {WOS:000271240500017},
url = {https://juser.fz-juelich.de/record/6107},
}