Download - GRAS SAF Status & Next Steps
11
GRAS SAF Status & Next Steps
Kent B. Lauritsen
Danish Meteorological Institute
Copenhagen, Denmark
-----
Contents
- Short introduction to the GRAS SAF system
- Status of refractivity product
- Next upgrades of the system
- 1dvar products and ROPP_PP processing
- ROPP software and plans
22
GRAS Satellite Application Facility Consortium
Leading Entity:Danish Meteorological Institute (Copenhagen, Denmark)Kent B. Lauritsen, Hans Gleisner, Kjartan Kinch, Johannes K. Nielsen, Frans
Rubek, Stig Syndergaard, Hallgeir Wilhelmsen
Partners: ECMWF (Reading, UK)Sean Healy
Institute d’Estudis Espacials de Catalunya (IEEC, Barcelona, Spain)
Estel Cardellach, Santi Oliveras
Met Office (Exeter, UK)Dave Offiler, Chris Burrows, Ian
Culverwell
Occultation Antenna
UKMO x
DMIx
IEECx
EUMETSATx
ECMWFx
33
The GRAS SAF objectives
Operational processing and archiving center for GRAS radio occultation (RO) data:- including additional third party RO data being processed by EUMETSAT CAF;- including reprocessing of RO data from EUMETSAT CAF and other data providers;
Products and software deliverables:
Near-real time (NRT) radio occultation products- operational products in NRT (refractivity, temperature, pressure, humidity);
Offline/climate radio occultation products- offline profile products (monthly), and reprocessed profiles;- offline gridded products (monthly), and reprocessed data sets: gridded data of bending angle, refractivity, temperature, humidity, geopotential height;
Radio Occultation Processing Package (ROPP)- routines for assimilation and processing of RO data;
44
NRT, Offline, and Climate processing overviewPhase, amplitude,
ground station observations,near-real time orbits
Phase, amplitude,ground station observations,
NRT/offline data
Bending angle profiles(L1, L2, LC)
Refractivity profiles
1D-Var algorithm
Ancillarytemperature, pressure,
and humidity, fromECMWF forecasts
Temperature,pressure, and
humidity profiles
GRAS SAFNRT Products
Bending angle profiles(ionosphere corrected and
statistically optimized)
Refractivity profiles
1D-Var algorithm
Temperature,pressure, and
humidity profiles
GRAS SAFOffline Products
Level 1a
Level 1b
Level 2
Produced byEUMETSAT CAF
Geometric optics inversion algorithm
Bending angle profiles(statistically optimized)
Abel transformalgorithm
CT2algorithm
Abel transformalgorithm
Level 2
Level 2
Re-processed data(zero/single/double diff.):
Phase, amplitude
Other RO data(COSMIC, CHAMP, ...):
Phase, amplitude
Bending angle profiles(ionosphere corrected and
statistically optimized)
Refractivity profiles
1D-Var algorithm
CT2algorithm
Abel transformalgorithm
Temperature,pressure, and
humidity profiles
Climate algorithms
Bending angle, refractivity,temperature, humidity, andgeopotential height grids
GRAS SAFClimate/Gridded Data
55
Recent and planned system upgrades
GRIB2 format- upgrading of GPAC to handle ECMWF’s new GRIB-2 format- done on May 17, 2011
L2 extrapolation and BA thinning- upgrade done in coordination with EUMETSAT- updated code running at EUMETSAT CGS GS2- planned for June/July (TBC)
Production, dissemination, and archiving of 1DVar products- code prepared, testing- upgrade planned for TBD
66
NRT refractivity product (GRM-01)
Produced from geometric optics (GO) level 1b bending angles (BAs) from GRAS/Metop-A data from EUMETSAT CAF
Limited information contents at low altitudes (due to GO and no RS data) Product version: 1.3 Number of registered GTS users: 19
77
REF statistics for the first 10 days of Dec 2010
88
NRT refractivity product (GRM-01): Plans
Plans:- L2 extrapolation: will increase penetration depth- Improve statistical optimization (SO) by using an enhanced
background climatology - Validate against COSMIC data processed to BA and Refractivity- Comparisons of ROPP_PP vs OCC/Invert- Switch to using ROPP_PP code in operations
Status on issues related to PPF upgrade preparations at DMI:- Analyses focusing on the inclusion of thinned bending angles in the PFS
files (done in Dec 2010 using PPF2.16 GS2 data)
- Analyses focusing on extrapolation of L2 bending angles with higher SLTA configuration (done in Feb 2011 using PPF2.17 offline data)
99
Penetration statistics with L2 extrapolation
1010
NRT 1DVar products: T and q
Status Produced from refractivity from (currently) geometric optics (GO) bending
angles Limited information content at low altitudes Limited information about humidity Product version: 1.0 Number of GTS users: n/a
Plans/ongoing:- Upgrade operational system with NRT 1DVar products: in preparation- Processing and comparison of GRAS and COSMIC data- Re-assess temperature and humidity information in the lower
troposphere - Handle cases with super saturation- Scientific assessment of prototype GRAS data for check-point review
in Jan 2012
1111
ROPP_PP processing of GRAS RS data
All processed GRAS RS profiles from 30 Sept 2007 included;
Comparison of ROPP_PP and Michael Gorbunov’s OCC codes for different choices of coordinates;
1212
ROPP package overview
GRAS Level 1b(CGS)
EPS/PFS
netCDFeps2netcdf
GRASLevel 2(SAF)
ropp2bufr(Thin or Full Level 1b/2)
BUFR
ropp_1dvar(for Q/C)
ropp_fm(as part of 3/4-D Var)
NWP VAR system
NWP User
netCDFropp_pp
ropp2bufr(Thin Level 1b)
ropp2bufr(Thin Level 2)
ropp_1dvar
netCDF
1313
Next release: ROPP-5
• ROPP-5 improvements over ROPP v4.1:• Inclusion of non-ideal gas effects (compressibility factors) in ropp_fm and
ropp_1dvar;
• Enhanced BUFR support in ropp_io – interfaces also with ECMWF library;
• Various bugfixes (including some in ropp_pp/OCC);
• Beta version built and put on website at end of March 2011.
• DRI review held at Met Office on 20 May 2011.
• ROPP-5 scheduled to be released early July 2011 after close-out meeting/telecon later in June.
1414
Plan for ROPP-6
• ROPP-6 in plan for release before end of CDOP in February 2012(Public release: Feb 2012; DRI: Dec 2011; Beta: Oct/Nov 2011)
• New/improved science to include: Ionosphere Correction
• New technical enhancements:• potentially netCDF-4/HDF5
• updated format for ECM’s (error covariance matrices)
• Tuning of ROPP_PP for GRAS offline data
1515
ROPP and data registered users
1616
Improving the timeliness of Metop-A global data
Using NASA's McMurdo station in Antarctica, near the South Pole;
Antarctic Data Acquisition (ADA) User trials in e.g. April, 2011:
Below is shown data from 19 April from 7:30z to 15:30z;
GRAS SAF system can handle higher data rates (but to get
the full increase in timeliness, system has to be “reconfigured”)
Figure from EUMETSAT
Min: 1h 28min
Min: 0h 41min
1717
fin