MORSE Input Files


When MORSE is run, the driver table (morse.drv) is always required. Additional input files are specified within various sections of the driver table.

MORSE Input Files
File Description Section Requirement Geometry
.atm Internal vertical grid, or *LEV Mandatory
1D atmospheric profile *ATM Optional
.fov Field-of-View shape *FOV Optional Limb
.glo 4D Climatological fields *ATM Optional
.ils Instrument lineshape *ILS Optional
.l1c Level 1C Data (apodised spectra) *L1C Mandatory
.mwl Microwindow list *MIC Optional
MW*.DAT Microwindow Database *MIC Optional
.noi Noise spectrum *L1C Mandatory Nadir
.orb 2D Orbital (matched) profiles *ATM Optional
Driver Table Optional Sections
File Description Requirement Geometry
*HIT *.hit HITRAN binary file Optional
*LUT *.tab Look-Up Tables Optional
*SFC *.sfc Surface emissivity spectrum Optional
*SVD *.svd MIPAS SVD-compressed Look-Up Tables Optional Limb
*XSC *.xsc Molecular Cross-Sections Optional


  1. Most locally-defined input files start with an arbitrary number of optional comment records, identified by the first character being '!'
  2. Blank records are ignored
  3. Numerical data are read free format unless otherwise specifed and text data is read either from specific positions within record or using spaces to distinguish fields (essentially free-format but without any requirement for quote marks around character fields).
The rest of this document details the format of input files which are not described elsewhere.


The following notation is used when describing the type of variable represented by each Field in the driver table. Storage values are nominal, and actually defined by the kind_dat.f90 module.
Type Description Storage
I Integer 4 bytes
R Real 4 bytes
D Double Precision 8 bytes
Cn Character string, length n n bytes

Noise Spectrum (*.noi)

Spectral variation of instrument noise
Only used in nadir-viewing

Filename specified in *L1C section

C80 Records
!CMNT [optional comment records]
WNO(1) NESR(1)
WNO(2) NESR(2)
!CMNT C80 Comment record(s) (optional) Record starts with '!'
NPTS I No. spectral points >1
WNO D Wavenumber [cm-1] >0
NESR R Noise radiance [nW/(cm2 sr cm-1)] >0

  1. For IASI (unlike MIPAS) it is assumed that the noise characteristics are almost constant, hence contained in separate file rather than included in the L1C data.
  2. The NESR spectral grid should overlap the the spectral range in the L1C data (hence a minimum value of NPTS=2) but need not be on the same spectral resolution.

iasi.noi (recommended IASI data)


Atmospheric 2D,3D,4D fields, interpolated to profile locations
Used as both a priori and initial guess for retrieved parameters as well as specifying profiles of non-retrieved quantities (p, T, VMRs).

Filename(s) specified in *ATM section

C80 Records
!CMNT optional comment records
DIM(1) DIM(2) ... DIM(NDIM)
Start repeat for each dimension ...j=1,NDIM
AXS(1,j) AXS(2,j) ... AXS(DIM(j),j)
End repeat
FLD(1) FLD(2) ...
*END Marker for end of header section
Start repeat for each Field k=1, NFLD
Start repeat for each Dimension j=1, NDIM
DAT(1,j,k) DAT(2,j,k) ...
... DAT(DIM(j),j,k)
*END Optional marker for end of file
!CMNT C80 Comment record(s) (optional) Record starts with '!'
RFMT R Format identification Currently set to 1.0
NDIM I No. tabulation dimensions 1:5
DIM(j) I Size of table dimension i
*DIM(j) C4 Label of table dimension i *HGT, *PRE, *LAT, *LON, *TIM or *DAY
AXS(i,j) R Axis value j of dimension i
NFLD I No. different data fields within file Read free-format
FLD(k) C* Field#k, eg 'TEM', 'CH4' Upper case, separated by spaces
DAT(i,j,k) R Value of field k at point i along dimension j

  1. These files are a way of supplying gridded climatological information (i.e. more than just a single profile as with the .atm files) which will be interpolated by MORSE to match the profile location and time.

ig2.glo (MIPAS 'IG2' climatological dataset)