1. Proposal for input/output data of GIRO application
Masaya Takahashi (JMA),
Bartolomeo Viticchie (EUMETSAT)
GRWG/GDWG web meeting, 24 June, 2014

2. Input/Output files of GIRO application
We propose both input and output files to be in NetCDF
Input: lunar observation and instrument SRF files, Output: lunar calibration file
Common format data: easy-to-handle in the executable
Detailed document and NetCDF template will be found on the GSICS Wiki
The contents are based on:
GSICS NetCDF convention
 Relies on the following netCDF conventions:
GSICS file naming convention
 Follows the rules given in the General File Naming Conventions section of the
W.M.O. Manual on The Global Telecommunication System
GRWG/GDWG web meeting, 24 June, 2014

3. General information about NetCDF
easy-to-understand User’s guide and tutorials
Utilities: many CUI/GUI apps, ncdump/ncgen are quite useful
ncdump: convert NetCDF file to text form (CDL)
ncgen: generates a NetCDF file or a C/FORTRAN code that creates a netCDF dataset from CDL
“NetCDF is a set of software libraries and self-describing, machine-independent data formats that support the creation, access, and sharing of array-oriented scientific data. NetCDF was developed and is maintained at Unidata. ...”
(from Unidata website above)
GRWG/GDWG web meeting, 24 June, 2014

4. Input-1: Lunar observation NetCDF
File name (e.g., MTSAT-2/Imager)
W_JP-JMA-MSC,VISNIR+SUBSET+MOON,MTSAT2+Imager_C_RJTD_ _01.nc
satellite and instrument name
lunar observation time as yyyyMMddhhmmss
To know the naming details, please refer to:
Each participant has to generate this file
Single file for each lunar occurrence, including all-channel information
Variable units: must be the same as those in a template
Recommend to use classic netCDF4
Could be used as “GSICS source dataset” in the future
TO STRESS: the file name follows an official (i.e. GSICS) convention. Participants should follow the filename template as indicated.
GRWG/GDWG web meeting, 24 June, 2014

5. global attributes: Lunar observation NetCDF
Please follow our proposal if you have a plan to share the lunar observation NetCDF within GSICS community in the future
NAME
CONTENT
Conventions
CF-1.6
Metadata_Conv entions
Unidata Dataset Discovery v1.0
standard_name_ vocabulary
CF Standard Name Table (Version 19, 22 March )
project
e.g. Global Space-based Inter-Calibration System
title
e.g. MSG-2+SEVIRI lunar imagtette file
summary
e.g. Lunar observation file
keywords
“free content”
references
TBD
institution
e.g. EUMETSAT
licence
“terms of use”
creator_name
e.g., EUMETSAT - European Organisation for the Exploitation of Meteorological Satellites
NAME
CONTENT
creator_
e.g.
creator_url
e.g.
instrument
e.g. MSG2 SEVIRI
instrument_wmo_code
e.g. (56, 207)
data_source
“free content” e.g., Level 1.0
date_created
YYYY-MM-DDTHH:MM:SSZ
date_modified
history
“free content” id
File name
wmo_data_category
101 for Imager data(satellite)
wmo_international_dat a_subcategory
0 for Multi-purpose VIS/IR imagery
processing_level
e.g. “v1.0.0”
doc_url
URL of document
doc_doi
DOI of document (if exists)
GRWG/GDWG web meeting, 24 June, 2014

6. dimensions/variables: Lunar observation NetCDF
NAME
VALUE
DESCRIPTION
chan
e.g. 4 for SEVIRI
Number of channels
chan_strlen
e.g. 6 for SEVIRI
Maximum length of variable: chan
date 1
Number of date
sat_ref_strlen 6
Maximum length of variable: sat_pos_ref (i.e. “ITRF93”)
sat_xyz 3
X, Y, and Z axis of satellite position
col, row
e.g. 499 for SEVIRI
Number of columns and rows of the imagette
Compulsory
Imagette (optional)
Additional (optional)
variables
NAME [dimension]
LONG NAME
UNITS
TYPE
date[date]
time of lunar observation
seconds since T00:00:00Z 
double precision floating point
channel_name[chan,chan_strlen]
channel identifier
character ,e.g. “VIS006”
sat_pos[sat_xyz]
satellite position km
sat_pos_ref[sat_ref_strlen]
satellite position x y z
character, either “J2000” or “ITRF93”
irr_obs[chan]
observed moon irradiance
W m-2 µm-1
rad_obs_imgt[row,col,chan]
observed moon radiance imagette
W sr-1 m-2 µm-1
dc_obs_imgt[row,col,chan]
observed moon digital counts imagette 1
32-bit integer array
moon_pix_thld[chan]
digital counts threshold for moon mask
32-bit integer
pix_solid_ang[chan]
pixel solid angle sr
ovrsamp_fa[chan]
oversampling factor
dc_obs[chan]
integrated digital counts of moon observation
dc_obs_offset[chan]
averaged digital counts offset of deep space
moon_pix_num[chan]
number of moon pixels
opr_slope[chan]
official calibration slope
W sr-1 m-2 µm-1 DC-1
opr_offset [chan]
official calibration offset
1 (i.e. DC)
TO STRESS: in the case when both the observables and the imagettes are provided, the imagette is used ONLY for check purposes. The observables as provided by the user are the values used for deriving the end results. In case of discrepancies, a output message will notify it but there will be no data substitution.
TO STRESS: in the case imagettes are provided, both counts and radiances must be given. It is necessary to avoid complexity in the code to apply the calibration formulaes.
GRWG/GDWG web meeting, 24 June, 2014
must be the same as that in the SRF netCDF
origin: lower-left

7. Example : Lunar observation NetCDF
MTSAT-2/Imager (1 visible channel)
Case 1) : Compulsory
Keep all variables in the NetCDF and fill invalid variables with a value of -999 (i.e. _FillValue)
Dimensions of col and row (# of lunar imagette pixels) -> 1
Values of rad_obs and dc_obs -> -999
File size: ~5KB
Case 2) : Compulsory + Imagette + Additional
Dimensions of col and row -> 700
File size: ~6MB
GRWG/GDWG web meeting, 24 June, 2014

8. Input-2: instrument SRF NetCDF
File name (e.g., Meteosat-10/SEVIRI):
W_XX-EUMETSAT-Darmstadt,VIS+IR+SRF,MSG3+SEVIRI_C_EUMG.nc
Each participant DOES NOT have to prepare this file
Generated by GDWG in 2013 using official SRFs provided by each GPRC
GOES-11/-12/-13/-15, Meteosat-7/-9, MTSAT-1R/-2, COMS
“This file was produced in support of GSICS activities and thus is not meant for public use although the data in the file is in the public domain.” (from docs on the NOAA GSICS Data server)
After some modification, files will be put on GSICS Wiki (or GSICS Data server)
How to generate new SRF NetCDF files
The GDWG (i.e. Masaya) will do it when official SRF file is provided
If it is impossible to share the file for some reasons, please let us know
GRWG/GDWG web meeting, 24 June, 2014

9. Output: Lunar calibration NetCDF
File name (e.g., Meteosat-7/MVIRI):
W_XX-EUMETSAT-Darmstadt,SATCAL+ROLOVISNIR,MET7+MVIRI_C_EUMG_ _01.nc
Single file contains all-time, all-channel information (following the GSICS approach adopted to generate inter-calibration products, like GEO-LEO-IR Re-Analysis Correction NetCDF)
Contents
Observation time, positions of satellite, Moon, Sun, observables, reference lunar irradiance, ...
Starting point for developing a GSICS product in the future
Concept: applicable to the future GSICS GEO-LEO VIS/NIR products
GRWG/GDWG web meeting, 24 June, 2014

10. global attributes: Lunar calibration NetCDF
Some differences from the lunar observation NetCDF
NAME
CONTENT
Conventions
CF-1.6
Metadata_Conve ntions
Unidata Dataset Discovery v1.0
standard_name_v ocabulary
CF Standard Name Table (Version 19, 22 March 2012)
project
e.g., Global Space-based Inter-Calibration System
title
e.g. GSICS MSG-2+SEVIRI vs ROLO1.0 lunar calibration file
summary
Lunar calibration file
keywords
“free content”
references
TBD
institution
“institution name” (e.g. EUMETSAT)
licence
“terms of use”
creator_name
e.g., EUMETSAT - European Organisation for the Exploitation of Meteorological Satellites
creator_
creator_url
NAME
CONTENT
instrument
e.g., MSG2 SEVIRI
instrument_wmo_code
(56, 207)
date_created
YYYY-MM-DDTHH:MM:SSZ
date_modified
history
“free content” id
file name
wmo_data_category
30 for Calibration dataset (satellite)
wmo_international_dat a_subcategory
5 for Re-Analysis Correction
processing_level
e.g. “v1.0.0”
atbd_url
ATBD URL
atbd_doi
ATBD DOI
time_coverage_start
time_coverage_end
phase_angle_min
2 [degree]
phase_angle_max
92 [degree]
reference_model
e.g. ROLO version 1.0
GRWG/GDWG web meeting, 24 June, 2014

11. dimensions: Lunar calibration NetCDF
NAME
VALUE
DESCRIPTION
chan
e.g. 4 for SEVIRI
Number of channels
chan_strlen
e.g. 6 for SEVIRI
Maximum length of variable: chan
date 1
Number of date
sat_ref_strlen 6
Maximum length of variable: sat_pos_ref (i.e. “ITRF93”)
sat_xyz 3
X, Y, and Z axis of satellite position
lambda_rolo 32
Number of ROLO spectrum
lambda_apollo
221
Number of APOLLO spectrum
obs_strlen
Length of lunar observation NetCDF file name
Differences from lunar observation NetCDF
GRWG/GDWG web meeting, 24 June, 2014

12. variables: Lunar calibration NetCDF
3 options: Basic, Partial: Basic+, Complete: Partial+
NAME
LONG NAME
UNITS
TYPE
date[date]
time of lunar observation
seconds since T00:00:00Z
double precision floating point
channel_name[chan,chan_strlen]
channel identifier
character, e.g. “VIS006”
central_wavelength[chan]
nominal channel central wavelength µm
irr_obs[date,chan]
observed moon irradiance
W m-2 µm-1
irr_rolo[date,chan]
rolo irradiance
dc_obs[date,chan]
integrated digital counts of lunar observation 1
32-bit integer
dc_obs_offset[date, chan]
averaged digital counts offset of deep space
moon_pix_num[date,chan]
number of moon pixels
pix_solid_ang[date,chan]
pixel solid angle sr
ovrsamp_fa[date,chan]
oversampling factor
moon_pix_thld[date,chan]
digital counts threshold for moon mask
sat_selen_lat[date ]
satellite selenographic latitude
degrees
sat_selen_lon[date]
satellite selenographic longitude
dist_sat_moon[date]
satellite moon distance km
sun_selen_lat[date]
sun selenographic latitude
sun_selen_lon[date]
sun selenographic longitude
dist_sun_moon[date]
sun moon distance AU
phase_ang[date]
moon phase angle
sat_pos_ref[sat_ref_strlen]
satellite position x y z
character, either “J2000” or “ITRF93”
sat_pos[date, sat_xyz]
satellite position
sun_pos[date, sat_xyz]
sun position
moon_pos[date, sat_xyz]
moon position
GRWG/GDWG web meeting, 24 June, 2014

13. variables: Lunar calibration NetCDF
3 options: Basic, Partial: Basic+, Complete: Partial+
NAME
LONG NAME
UNITS
TYPE
rolo_spectr[date, chan, lambda_rolo]
rolo reflectance spectrum at rolo wavelength 1
double precision floating point
rolo_lambdas[lambda_rolo]
rolo wavelength µm
rolo_smooth_spectr[date, chan, lambda_apollo]
rolo reflectance spectrum at apollo wavelength
apollo_lambdas[lambda_apollo]
apollo wavelength m
double precision
moon_obs_file[date, obs_strlen]
lunar observation file name
character
GRWG/GDWG web meeting, 24 June, 2014

14. Points of contact If you have any questions about:
Generating lunar observation NetCDF
Generating new instrument SRF NetCDF
Troubleshooting of GIRO
etc.
Please us!
Before asking, please check updates of documentations on the GSICS wiki (
Masaya Takahashi (EUMETSAT visiting scientist from JMA):
Masaya.Takahashi -at- eumetsat.int (or masa.takahashi80 -at- gmail.com)
Bartolomeo Viticchie:
Bartolomeo.Viticchie -at- eumetsat.int
GRWG/GDWG web meeting, 24 June, 2014

15. Thanks for your attention
GRWG/GDWG web meeting, 24 June, 2014