Subject: | NSA/SONDE/C1 - Incorrect surface altitude |
DataStreams: | nsasondeC1.00, nsasondewnpnC1.b1
|
Description: | The value of the station altitude (relative to mean sea level) is
incorrect in all NSA radiosonde files prior to 2/14/2004. The correct
value is 8 m. The incorrect value can be different. Prior to 4/24/2002
(in platform nsaisssonde...) it was given as 12 m. From 4/24/2002 to
2/13/2004 (in platform nsasondewnpn...) it is almost always given as
27 m (sometimes [rarely] 17 m). |
Suggestions: | Because the altitude computation is based on the pressure measurement
the error is linear. A general method to correct the problem is outlined
in the following pseudocode:
SET SurfAlt = 8.
GET Array_of_alt_values
SUBSTRACT first alt_value from all alt_values
ADD SurfAlt to alt_values |
Measurements: | nsasondeC1.00: - (Raw data stream - documentation not supported)
more
nsasondewnpnC1.b1: more
|