IRFP-01
Metro Review
b. Picture is the result of reflected sunlight
(1) Clouds are an excellent reflector of sunlight
(2) Neither the Earth’s atmosphere nor empty space reflects
sunlight; therefore, the background will always be black
(3) Reflectivity table: (thick clouds appear white, thin clouds
appear darker)
(a) Cumulonimbus - 92%
(b) Thick Cirrostratus - 74%
(c) Thick Stratocumulus - 68%
(d) Thin Stratus - 42%
(e) Sand, No Foliage - 27%
(f) Sand and Brushwood - 17%
(g) Water Surfaces - 9%
NOTE: Terrain has intermediate to low reflectivity and
will appear as some shade of grey. Water appears
almost black. Land/water contrast will normally be
good.
Fig 41: Infrared
Picture
1. Everything with a temperature above absolute zero radiates energy
2. Wave length of energy varies with temperature
3. GOES measures energy level at specific wave lengths
4. Earth receivers convert energy measurements to temperatures
a. IR imagery portrays different temperatures as black (very
warm), white (very cold), or some shade of grey
b. High clouds are very cold so they appear white; mid-level
clouds are warmer, so they appear as some shade of grey; low
clouds and/or fog often are the same temperature as the
surrounding terrain and cannot be distinguished at all
5. Enhanced IR pictures
a. Meteorologist has the option of assigning shades of grey to
specific temperatures which allows specific items, i.e.,
thunderstorms, to be highlighted
(8-97) Original
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