Name Template: PUB/MISSION/level2/brfPrf/YYYY.DDD/bfrPrf_IIII.YYYY.DDD.HH.MM.GGG_SSSS.VVVV_nc
|DDD||Day of year|
|GGG||GNSS id (G28 = GPS satellite 28)|
|IIII||Mission ID (CHAM, SACC, CO01-06, GPSM, etc)|
|LLL||LEO number (1-6 for COSMIC)|
|MISSION||Mission ID (eight characters or less--champ, champrt, sacc, sacctst, etc)|
|PUB||Base directory for the pub hierarchy|
|SSSS||Subtype (an ID which tells the command options used in generating this file)|
|VVVV||Version (an ID which tells the version of all codes using in generating thie file)|
A low resolution (adjustable, currently 200 meter) atmospheric profile in the BUFR format useful to weather
modelers. Contains data taken from the atmPhs, atmPrf and
wetPrf files, including:
- Occultation location and time, other header information
- Bending angle versus impact parameter profiles
- Refractivity versus MSL geometric height profiles
- Pressure, Temperature and Moisture versus geopotential height profiles
The complete format documentation is in the
Version 2.3 WMO FM94 (BUFR) Specification (PDF) by Dave Offiler of the UK Met Office.
Some notes are in order as to the UCAR/COSMIC implementation of the above BUFR format.
The original data from the atmPrf files are specified on a high
rate 50 Hz grid (3000 values for a 60 second occultation). Certain
data (lat, lon, azim, bending angle, impact parameter, refractivity)
are first interpolated onto a uniform high resolution grid, then
Fourier smoothed and finally interpolated onto the 200m grid.
Higher level data (pressure, temperature, specific humidity) is supplied
in 100 meter resolution in the wetPrf files and
is simply decimated to get 200m resolution data.
The current 'percent confidence' vector for both bending angle and
refractivity is somewhat rudimentary. It is a simple exponential
curve generated from the bending angle noise between 60 and 80 km,
modified by several other scalar data quality indicators.
The error values for bending angle and refractivity are only given
for high altitude data (above approximately 20km). We hope to supply
complete error profiles soon.
There are currently no error values supplied for pressure, temperature
and specific humidity.