WMOD00405

• Title: Thermodynamic Features Affecting Convective Cloud Growth and Dynamic Seeding: A Comparitive Summary of HIPLEX Soundings 1975-1977
• Date: 7/1/1981
• Weather Modification - Doc Type: Report

Table 4. Sample means for different cloud types observed at
Miles City, Montana in 1976-77 during days for which
satellite population statistics of convective clouds were available

Variable

Group 1 mean Group 2 mean P-value*
Cumulus Cumulonimbus

Sample size n ; 9 n = 28
Cloud-base temperature (OC) 3.89 6.96 0.013
Surface convective temperature 3.89 8.36 .025
Mean lapse rate for layer
100 to 150 mbar a.g.l. ('C/100 m) - 0.81 - 0.67 .012
Mean lapse rate for layer
150 to 200 mbar a.g.l. (OC/100 m) - 0.83 - 0.60 .005
Mean mixing ratio for layer
surface to 50 mbar a.g.l. 7.24 9.07 .022
Mean mixing ratio for layer
surface to 100 mbar a.g.l. (g/kg) 6.71 8.59 .019
Natural cloud depth for 0.5-km
initial radius (km) 0.30 1.54 .008
Cloud-top temperature for 0.5-km
initial radius (OC) - 1. 28 - 6.23 .059
Cloud-top height for 0.5-km
initial radius (km m.s.l.) 5.50 7.01 .036
Natural cloud depth for 1.0-km
initial radius (km) 0.42 2.44 .003
Cloud-top temperature for 1.0-km
initial radius (OC) 2.09 -12.62 .008
Total supercooled water content
for 1.0-km initial radius (g/m3) 0.18 1.32 .018
Natural cloud depth** for 1.5-km
initial radius (km) 0.51 3.01 .003
Cloud-top temperature** for 1.5-km
initial radius (OC) 2.57 -16.76 .004
Total supercooled water content**
for 1.5-km initial radius (g/m3) 0.33 2.23 .017
Natural cloud depth for 10.0-km
initial radius (km) 1.10 5.22 .009
Modified cloud depth for 10.0-km
initial radius (km) 1.19 5.49 .Oll
Cloud-top temperature for 10.0-km
initial radius ('C) - 7.39 -34.46 .012
Total supercooled water content
for 10.0-km initial radius (g/kg) 1.10 6.79 .016
Cloud type n 12 Cumulus Congestus n = 28 Cumul on imbus
Cloud-base height (km m.s.l.) 3.74 3.01 0.013
Cloud-base temperature (OC) 2.42 6.96 .001
Surface mixing ratio (g/kg) 8.22 9.76 .025
Mean mixin9 ratio for layer
from surface to 50 mbar a.g.l. (g/kg) 7.33 9.07 .003
Mean mixing ratio for layer
from surface to 100 mbar a.g.l. (g/kg) 6.87 8.59 .002
Mean mixing ratio for layer
from 100 to 150 mbar a.g.l. (g/kg) 5.69 7.42 .000
Mean mixing ratio for layer
from 150 to 200 mbar a.g.l. 4.81 6.36 .000
Total supercoo1ed water content (g/kg)
for 1.0-km initial radius (g/kg) 0.08 1.32 .007
Total supercooled water content
for 1.5-km initial radius (g/kg) .32 2.23 .009
Total supercooled water content
for 2.0-km initial radius (g/kg) .48 3.06 .009
Total supercooled water content
for 3.0-km initial radius (g/kg) .76 4.ll .012
Total supercooled water content
for 10.0-km initial radius (g/kg) 1.65 6.79 .017

*All variables whose P-values were < 0.060 are listed in table 4.
**Similar variab1es were significant for the 2.0- and 3.0-km initial radius cases.

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