status of cosmic and missions of opportunity bill schreiner and cdaac team cosmic retreat nov 4,...
TRANSCRIPT
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