amend check ongeop in ropp_io_rangecheck?

[Ian Culverwell]

ropp_io_rangecheck.f90 currently zaps all lev2b data unless there's at least one valid geopotential, thus:

! Every level must have a valid geopotential height value;
! if all are missing, then set whole L2b profile to zero length.
! If only some heights are missing, filter them out

    idx => WHERE ( Lev2b%Geop > ropp_MDTV, nidx )
    IF ( nidx == 0 ) THEN
      Lev2b%Npoints = 0
    ELSE IF ( nidx < Lev2b%Npoints ) THEN
      Lev2b%Npoints             = nidx
      Lev2b%Geop(1:nidx)        = Lev2b%Geop(idx)
      Lev2b%Geop_Sigma(1:nidx)  = Lev2b%Geop_Sigma(idx)
      Lev2b%Press(1:nidx)       = Lev2b%Press(idx)
      Lev2b%Press_Sigma(1:nidx) = Lev2b%Press_Sigma(idx)
      Lev2b%Temp(1:nidx)        = Lev2b%Temp(idx)
      Lev2b%Temp_Sigma(1:nidx)  = Lev2b%Temp_Sigma(idx)
      Lev2b%SHum(1:nidx)        = Lev2b%SHum(idx)
      Lev2b%SHum_Sigma(1:nidx)  = Lev2b%SHum_Sigma(idx)
      Lev2b%Meteo_Qual(1:nidx)  = Lev2b%Meteo_Qual(idx)
    END IF

Unfortunately the bgr files provided at ​http://www.romsaf.org/product_archive.php do have precisely this feature (eg see bgr20150401_024913_M01_1290556912_N0021_XXXX.nc attached). Therefore the RO processing tool provided by the ROM SAF cannot read the RO data provided by the ROM SAF. This is obviously not exactly ideal.

Possible solutions:

• Amend the range-checker so that it only zaps the lev2b fields if all geops and (say) all temps are missing;
• Get the archive regenerated with valid geops in the bgr files.
• Manually (eg with ncap2 -s"geop=float(geop*0-999)" bgr.nc -O temp.nc ; ncks -a temp.nc -O bgr.nc) set the geops to non-missing values.

Why are the geops missing from the bgr files? Ask DMI.

[Ian Culverwell]

bgr20150401_024913_M01_1290556912_N0021_XXXX.nc

[Ian Culverwell]

DMI's reponse, and my commitment to update [[[ropp_io_rangecheck}}} to account for missing geops, are documented in Helpdesk enq 233: ​http://www.romsaf.org/view_enquiry.php?id=233

[Ian Culverwell]

A temporary solution, to be applied until valid geopotentials are included in the 137L geop files, has been committed at r4948. It generates the output message

WARNING (from ropp_io_read):  No valid geopotentials found, but valid temperatures and humidities are present.
  This is OK for ECMWF fields provided that valid Ak and Bk coefficients and surface pressures are present.

[Ian Culverwell]

Checks out OK on 137L file (see #460). Closing ticket.