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PDS Information
Find a Node - Use these links to navigate to any of the 8 publicly accessible PDS Nodes.

This bar indicates that you are within the PDS enterprise which includes 6 science discipline nodes and 2 support nodes which are overseen by the Project Management Office at NASA's Goddard Space Flight Center (GSFC). Each node is led by an expert in the subject discipline, supported by an advisory group of other practitioners of that discipline, and subject to selection and approval under a regular NASA Research Announcement.

Cloud Properties


from NOAA chart

low clouds:

up to 6500 ft
up to 2 Km
up to 800 mBar (275 K)
Sc,St,Cu,Cb (Stratocumulus,Stratus,Cumulus,Cumulonimbus)

middle clouds:

6500 ft to 23,000 ft
2 Km to 7 Km
800 mBar to 400 mBar (240 K)
Ac,As,Ns (Altocumulus, Altostratus, Nimbostratus)

high clouds:

16,500 to 45,000 ft
5 Km to 13.75 Km
530 mBar (255 K) to 140 mBar (216 K)
Ci,Cc,Cs (Cirrus, Cirrocumulus, Cirrostratus)

ReffVeff (Hansen, 1971)
Fair Weather cumulus5.560.111
Altostratus7.010.113
Stratus11.190.193
Cumulus congestus10.480.147
Stratocumulus5.330.118
Nimbostratus10.810.143

Earth is typically covered about 50%
average precipitable water is about 2.5 cm
average time aloft is 9 days (from 100 cm of rain/year)
in thunderstorm approximately 10% of water is released

suspended droplets 1 µm to 100 µm
cloud over continents have smaller droplets