RS92-FP(day)
-60
-40
-20
Yangjiang (5)
Alajuela (3)
Lindenberg (43)
Sodankyla (13)
Boulder (16)
0
RS92-CFH(night)
-80
Temperature [oC]
Temperature [oC]
-80
-60
-40
-20
Yangjiang (4)
Alajuela (4)
Lindenberg (52)
Sodankyla (12)
0
20
20
-40
-20
0
20
40
Water vapor mixing ratio difference [%]
-40
-20
0
20
40
Water vapor mixing ratio difference [%]
Fig. 18. Comparison of humidity profiles from GRUAN processed RS92 and coincident frost point (FP) hygrometer data. Top: daytime flights, bottom: nighttime flights. Data are gridded in 500 m wide bins, and plotted
with ambient temperature as the vertical scale. The analysis is restricted to the troposphere. The solid circles
represent the relative difference RS92 – FP with respect to the FP humidity, and the bars indicate the statistical
uncertainty (standard deviation). All data presented here are for the CFH except for the NOAA FPH data from
Boulder, the number of soundings at each site is given in brackets. The approximate water volume mixing ratios
at various temperature levels are given in Table 7.
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