Description
Aspen can either use the reported GPS position info from the sonde or integrate the poisiton using the horizontal winds. Aspen reports the observed position by default, but can be configured to integrate the sonde location from the initial launch position. If a time gap of greater than maximum position integration interval occurs in the wind measurements, the integration terminates.
The position integration requires an initial position to start the integration. Similarly, an initial wind speed and direction at the launch point are used in the integration. If these are not available, Aspen will use the first Q/C wind speed and direction as the launch point value. This unjustified assumption thus assumes a constant wind profile at launch, in the absence of a wind measurement at the launch point.
Formula
Source
Edit me