TY  - JOUR
AU  - Neis, P.
AU  - Smit, Herman G.J.
AU  - Krämer, M.
AU  - Spelten, N.
AU  - Petzold, Andreas
TI  - Evaluation of the MOZAIC Capacitive Hygrometer during the airborne field study CIRRUS-III
JO  - Atmospheric measurement techniques
VL  - 8
IS  - 3
SN  - 1867-8548
CY  - Katlenburg-Lindau
PB  - Copernicus
M1  - FZJ-2015-06600
SP  - 1233 - 1243
PY  - 2015
AB  - The MOZAIC Capacitive Hygrometer (MCH) is usually operated aboard passenger aircraft in the framework of MOZAIC (Measurement of Ozone by Airbus In-Service Aircraft) for measuring atmospheric relative humidity (RH). In order to evaluate the performance of the MCH, the instrument was operated aboard a Learjet 35A research aircraft as part of the CIRRUS-III field study together with a closed-cell Lyman-α fluorescence hygrometer (Fast in situ Stratospheric Hygrometer, or FISH) and an open-path tunable diode laser system (Open-path Jülich Stratospheric TDL ExpeRiment, or OJSTER) for water vapour measurement. After reducing the CIRRUS-III data set to data corresponding to MOZAIC aircraft operation conditions, the 1 Hz RH data cross correlation between the MCH and reference instruments FISH (clear sky) and OJSTER (in-cirrus) yielded a remarkably good agreement of R2 = 0.92 and slope m = 1.02 and provided a MCH uncertainty of 5% RH. Probability distribution functions of RH deduced from the MCH and reference instruments agreed well between 10 and 70% RH with respect to liquid water in the ambient temperature range of ca. −70 to −40 °C. The use of MCH data is limited to sensor temperatures above the calibration limit of Tsensor = −40 °C (corresponds to ambient temperature of Tambient = −70 °C at typical cruising speed of long-haul passenger aircraft). Good performance of the MCH for clear sky as well as for in-cirrus conditions demonstrated the sensor robustness also for operation inside ice clouds.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000352158300017
DO  - DOI:10.5194/amt-8-1233-2015
UR  - https://juser.fz-juelich.de/record/276123
ER  -