International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B2. Istanbul 2004 
  
  
1200 UTC cloud forecast data predictions in the 
Figure 3. 
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20°N 
  
F igure 3. Cloud Forecast information 
The legend also shows the cloud cover percentage 
for that day. For example the red color represent 
the area will be totally or 100 percent cloud 
covered. The yellow one represents the cloud 
cover will be 10 percent for the area and the beige 
one represent the area will be totally cloud free or 
0 percent cloud covered. After getting 4 days forth 
cloud cover information for the whole 
communication cone from the meteorological 
service provider, the day after the new forecast 
information is updated with the more precise data 
for the upcoming days. Due to the prediction or 
iteration probability, sometimes the subjected area 
for the activity window could be cbud covered but 
the day after it can be clearer with the new 
iteration for that day. 
Once the forecast data is near to the subjected day 
the cloud cover information will be more accurate. 
Then we decide take or don't take this activity 
window time depending on the cloud cover over 
the subjected area. Sometimes this prediction can 
give faulty information since it has a mathematical 
model and iteration method while creating this 
valuable information. Due to the wrong iteration it 
can cause faulty information. However, this cloud 
  
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forecast information is very useful and very 
effective while selecting satellite passes. 
  
Figure 4. A meteorological satellite print out 
overlaying with country borders. 
3.2. Meteorological Satellite Data Usage 
The Space Imaging Eurasia company is using 
every kind of weather forecast information to 
gather into the collection optimization process. 
One of the most important one among these is the 
real time weather data coming from 
meteorological satellites. Meteorological service 
provider is sending half an hour basis currently 
available satellites meteosat and noaa data to the 
Space Imaging Eurasia ground station via ftp. 
Then satellite operator takes these images and 
compares with the previous image and with an 
animation tool the half an hour basis received 
images puts together and an animation is created. 
Then the cloud movement above the subject area 
is observed and if the area is cloudy then another 
cloud free region is scheduled by the operator. 
This process is continued up to 20 m inutes prior to 
contact with the IKONOS satellite 
3.3. Meteogram Data 
Sometimes we need the use another tool to 
compare with the cloud cover information and 
meteorological satellite data. The meteogram data 
is used to support to the cloud cover information 
and it also include the humidity with a given hPa, 
temperature, pressure, wind at a given height of 
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