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Status of COSMIC and Missions of Opportunity
Bill Schreiner
and CDAAC Team
COSMIC Retreat
Nov 4, 2010
CDAAC
NESDIS
GTS
NCEP
ECMWF
CWB
UKMO
Canada Met.
JMA
1500-2000 WMOBUFR Files per day withLatency ~ 75-90min
Getting COSMIC Results to Weather Centers
JCSDA
MeteoFrance
COSMIC Operational Processing
Science & Archive
TACC
AFWA
Input Data- COSMIC data- Attitude data- GPS ground data- GPS NDM Bits- GFS Forecast- IGS/IGU ORB/CLK- Bernese Config files
ResearchCommunity
SFTP
UCAR/Unidata’sLDM
WGET
RTSs:AlaskaNorwayMcMurdoWallopsNy-alesundCordobaAF/Hanscom
Providing data to > 1,350 registered users from 56 countries
Successful COSMIC Profiles 4/21/06-11/1/10
Neutral Atmosphere ~ 2.5MIonosphere EDPs ~ 2.6M
• LEO POD and excess phase (<15 cm, <0.15mm/s 3D rms)• ~2.6M neutral atmospheric profiles:
- Bending angle noise ~1.5 micro-rad- Refractivity precision 0.1-0.2 % between 8-30km
• > 3M Absolute TEC data arcs:- Absolute accuracy ~ 2-3 TECU (being evaluated)- Relative accuracy ~ 0.0024 TECU at 1-Hz
• ~2.6M Electron Density Profiles:- NmF2 (F2 layer peak) Accuracy ~20% (compared to Ionosondes)- hmF2 (F2 layer height) Accuracy ~20 km (compared to Ionosondes)
• Scintillation Indices (S4):- ~2.6M available from occultation profile events (altitudes < 120 km)- 1 Hz data available from > 3M line of sight tracks to all GPS in view
• TIP Night-side Radiances: - TIP set new standard for sensitivity of UV instruments, ~500
counts/s/Rayleigh- > 17,800 hours of quality controlled data
COSMIC Data Products
Current COSMIC Spacecraft/Payload Status
FM1 FM2 FM3 FM4 FM5 FM6
Space-craft
Batteryconcern
- Lost 1 of 2 solar arrays-Average ~50 % duty cycle- Battery concern
- Frozen solar array drive- Average ~50% duty cycle- Lost contact Aug 1, 2010
Batteryconcern
LostcontactSep 26,2010
Batteryconcern
GOXPayload
-POD-01 low SNR
- - -POD-01 low SNR- OFF
- Lost POD-00
POD-00,03 low SNR
GPS RO Firmware Update Status
• Firmware version 4.5.3 improvements tested on FM1 from Oct 1-9, 2010- Transition from OL to CL for rising occultations NOT improved- L2C tracking still has problems
- ½ cycle slip problem fixed - SNRs lower than expected by ½- No L2C rising occultations of good quality
- Tracked deep signals ~ -350 km HSL- Collected 50 Hz L1 C/A amplitude data on reference satellites- Tested RFI snooper (diagnostic SNR information)- Improved logging of OL model information
• JPL is investigating problems with 4.5.3• FM1 running version 4.5.3 without new capability• Upload to other FMs when JPL provides update
Testing of deep OL tracking (down to HSL=-350km) on FM-1 on Oct.5-6, 2010.
1) Down to what heights the LT RO signals can be observed and need to be tracked?2) What other signals (contaminant to RO) are observed?
Lower tropospheric RO signalobserved down to -300 km.Missing deep signals results innegative inversion bias in BA.
Non-RO signal presumablyfrom another (GPS) satellite.Not a significant error source.
Unknown non-RO signal(the same 50 Hz modulationas of the RO signal).
GPS RO Firmware Update Status
• Hopefully version 4.5.3 will improve quality and quantity of occultations
• UCAR recently discovered firmware bug affecting FM6 (tracking very few rising occultations). Fixed with command upload.
• Reduce POD satellites tracked to increase channels for occultation tracking
• UCAR and JPL will continue to upload/verify firmware enhancements to keep COSMIC mission productive
GNSS RO Possible Missions of Opportunity (MOOS)
(Excluding NASA Decadal Missions)
GNSS RO Possible Missions of Opportunity
Mission Launch-Duration
GNSS RO
Payload
Orbit (alt/inc/ LT) # Occs
Per day
Operational/Real-Time
F7/C2 2015 JPL TriG (GPS,Galileo)
800km/72,24°/- >8,000 Yes
METOP-B 2012 GRAS (GPS) 817km/98.7°/09:30LT ~600 Yes
OceanSat-2 2009 ROSA (GPS) 720km/98.3°/12:00LT ~500 No
KOMPSAT-5 2010 IGOR+ (GPS) 685km/98.5°/06:00LT ~500 No
Megha-Tropiques TBD ROSA (GPS) 867km/20°/- ~500 No
SAC-D TBD ROSA (GPS) 657km/98.5°/10:15LT ~500 No
TanDEM-X 20 IGOR (GPS) 514km/97.4°/18:00LT ~500 No
PAZ 2012 IGOR+ (GPS) 510km/97.4°/- ~500 No
EQUARS 2012 IGOR (GPS) 750km/20°/- ~500 No
CNOFS 2008 BlackJack (GPS) 853/405km/13°/- ~250 Best effort
SAC-C 2000 BlackJack 715km/98.5°/10:15LT ~200 Best effort
Missions of OpportunitySAC-C (Satélite de Aplicaciones Cientificas – C)
• Argentinian CONAE mission launched Nov 2000
• 715km altitude, 98° inclination, 10:15 LT
• JPL BlackJack, Open Loop, four single patch antenna
• Near real-time data provided by Germany’s GFZ and CONAE
• CDAAC providing 140-180 occultations per day to NOAA
• ~ 50-60% success from tracked profiles
• CDAAC working with Tom Meehan and CONAE to- configure GPS receiver to track rising occultations all day (now only 10-18 UTC)- reduce negative impact of aging oscillator
• CDAAC still vetting near real-time SAC-C data
Near Real-time SAC-C/COSMICGlobal stats
SAC-C COSMIC
Missions of OpportunityC/NOFS CORISS
• Communication/Navigation Outage Forecast System (C/NOFS)
• USAF mission launched Apr 16, 2008
• 400km X 850km, 13° inclination
• C/NOFS Occultation Receiver for Ionospheric Sensing and Specification (CORISS)
• JPL/Aerospace developed, Closed Loop, single patch antenna
• AF/Hanscom providing near real-time data from AFSCN network
• CDAAC providing 125-150 tropical occultations per day (~ 3 COSMIC FMs) to NOAA
• Profiles truncated below 8 km due to CL tracking limitations
• Only day-side occultations, UCAR working with Paul Straus to modify occultation tracking to get night-side data
• Possibility to upload OL firmware, but cpu limited
• CDAAC still vetting near real-time C/NOFS data
C/NOFS CORISS20<Lat<30
C/NOFS COSMIC
8km cutoff
Missions of OpportunityMetop-A/GRAS
• EUMETSAT mission launched 2006
• 820km, 98.7° inclination, 09:30 LT
• GRAS (GNSS Receiver for Atmospheric Sounding) Occultation Receiver
• High gain antenna, USO for zero-differencing
• UCAR/COSMIC funded by EUMETSAT to investigate Metop/GRAS structural uncertainty with closed loop data. Chris presenting final report now in Darmstadt.
• UCAR/COSMIC US funding used to develop open loop processing
• CDAAC has initiated CL/OL post-processing of Metop/GRAS data
• CDAAC could process near real-time data that is provided by NOAA
Metop/GRAS Study Summary
UCAR-EUMETSAT: 2007.274• Orbits estimated at
EUMETSAT and UCAR show no significant bias
• UCAR -EUMETSAT BA’s agree without any bias
• BA differences consistent with RO-Trends CHAMP comparisons
• Gaps in GRAS data contribute to structural uncertainty below 10 km
• GRAS zero difference processing reduces noise in stratospheric BA profiles
Missions of Opportunity
• TerraSAR-X, German mission, Launch Jun 2007- BRE IGOR- GFZ providing NRT ~200 setting profiles to GTS (UCAR assisted GFZ in
debugging problem)
• Tandem-X, German mission, Launch Jun 2010- BRE IGOR- Identical orbit as TerraSAR-X, useful for scientific studies
• OCEANSAT-2, Indian mission, Launch Sept 2009- ROSA receiver- Yaw-biased attitude, 35 degrees- Commissioning phase, no data available
• KOMPSAT-5, Korean mission, IGOR+, Launch 2010?- BRE IGOR+
• PAZ, Spanish mission, IGOR+, Launch in Jan 2012- IGOR+- Tom Meehan says firmware must be modified to provide data useful for RO.
This effort is not funded