Satellite Upper Air Network (SUAN)Satellite Upper Air Network (SUAN)andand

the Climate Retrieval Problemthe Climate Retrieval Problem

Tony RealeTony RealeNOAA/NESDIS, Suitland, Md. NOAA/NESDIS, Suitland, Md.

(tony.reale@noaa.gov)(tony.reale@noaa.gov)

Frank TilleyFrank TilleyRaytheon Corporation, Landover Md.Raytheon Corporation, Landover Md.

Workshop On Upper Air Workshop On Upper Air Observations Observations Boulder, Co. Boulder, Co.

February 8-10, 2005February 8-10, 2005

What is the Mission of the Radiosondes ?( Past vs Present vs Future )

Is There an Optimal Sampling Strategy ?( Synoptic vs Satellite Coincident vs ??? )

Satellite Upper Air Satellite Upper Air NetworkNetwork (SUAN) (SUAN)

• Global network of radiosonde sites Global network of radiosonde sites providing providing “standard”“standard” measurements measurements coincident with NOAA polar satellite coincident with NOAA polar satellite overpass overpass

• SUAN Report (Reale and Thorne)SUAN Report (Reale and Thorne)– ““http://www.orbit.nesdis.noaa.gov/smcd/opdb/poes/suan”http://www.orbit.nesdis.noaa.gov/smcd/opdb/poes/suan”

HistorHistory y

• UKMO Workshop on Vertical Temperature Trends (September, 2004) UKMO Workshop on Vertical Temperature Trends (September, 2004)

• WMO/AOPC (Geneva, April, 2004)WMO/AOPC (Geneva, April, 2004)– Subset of GUAN … “supersitesSubset of GUAN … “supersites””

• International ATOVS Study Conference (November, 2003)International ATOVS Study Conference (November, 2003)– Recommendation to pursue deployment through WMO DocumentRecommendation to pursue deployment through WMO Document

• White Paper: Creating Climate Data Records from NOAA Operational White Paper: Creating Climate Data Records from NOAA Operational Satellites (August, 2003). (Goldberg and Bates)Satellites (August, 2003). (Goldberg and Bates)– Section 4.2.1, Observing System Performance Monitoring (visit ITSC web page: Section 4.2.1, Observing System Performance Monitoring (visit ITSC web page:

http://cimss.ssec.wisc.edu/itwg/)http://cimss.ssec.wisc.edu/itwg/)

• Workshop to Improve Usefulness of Radiosondes (March, 2003)Workshop to Improve Usefulness of Radiosondes (March, 2003)– formal “unveiling” of SUAN, underlying concepts and evolving compensatory formal “unveiling” of SUAN, underlying concepts and evolving compensatory

roles of global radiosondes and polar satellites to serve as transfer standards ... roles of global radiosondes and polar satellites to serve as transfer standards ...

• NOAA Council on Long-Term Climate Monitoring (Jan., 2003)NOAA Council on Long-Term Climate Monitoring (Jan., 2003)– includes specific recommendations for “integrated global observing systems includes specific recommendations for “integrated global observing systems

which include reference radiosonde and overflying satellite observations … which include reference radiosonde and overflying satellite observations … with with goal of accurate, long term monirtoring of global temperature and goal of accurate, long term monirtoring of global temperature and moisturemoisture ... ...

CANDIDATE SITE CANDIDATE SITE SELECTIONSELECTION• Subset of GUAN (150) … “Subset of GUAN (150) … “super-super-

sitessites””– Active and Reliable ( Active and Reliable ( GreenGreen, , BlueBlue, , Red Red ) )

((UKMO, w/McCarthy; NESDIS, UKMO, w/McCarthy; NESDIS, w/Tilleyw/Tilley))

– Global/RobustGlobal/Robust– Low terrain (500m; 950mb) Low terrain (500m; 950mb) – Non-coastalNon-coastal

• ARM SitesARM Sites ( (BlackBlack))

• SHIPS SHIPS

# indicates current NWS sites (11)

# ARM sites (5)

20 Sea18 Land4 Sea-Ice

Primary SUAN Primary SUAN CandidatesCandidates

Alternate SUAN Alternate SUAN SitesSites

Super-Super-Sites Sites

• Standard Reference SondesStandard Reference Sondes– Temperature,Temperature, moisture, wmoisture, wind, surface …ind, surface …– 5 mb5 mb

• Ground MeasurementsGround Measurements– Lidars, GPS, clouds, surfaceLidars, GPS, clouds, surface ……

• R & DR & D– dual launches …dual launches …

WMO/AOPC in April 2004 :

Program To Program To Include:Include:

• Generation and Distribution of Launch Schedules Generation and Distribution of Launch Schedules (…45 minutes before overpass) (…45 minutes before overpass)– Fixed sitesFixed sites– ShipsShips

• Metadata Records … corrections, site protocols Metadata Records … corrections, site protocols ……

• Network Performance Monitoring/Feedback Network Performance Monitoring/Feedback

• International Coordination … WMO International Coordination … WMO

Program Program (continued):(continued):

• Integration into NESDIS Operational Sounding Product Systems Integration into NESDIS Operational Sounding Product Systems (ATOVS, METOP, NPP, NPOESS … )(ATOVS, METOP, NPP, NPOESS … )

• Relational Collocation File Structure (Raobs, raw satellite, level 1 …)Relational Collocation File Structure (Raobs, raw satellite, level 1 …)

• Open to Expansion, i.e., other satellites (i.e., GPS ...) and data (i.e., Open to Expansion, i.e., other satellites (i.e., GPS ...) and data (i.e., Ground, ACARS, Dropsondes …) Ground, ACARS, Dropsondes …)

• Accessible Archive (Data, Software readers) … Web-based ?Accessible Archive (Data, Software readers) … Web-based ?

• R & D Impact … R & D Impact …

How Many How Many ObservationsObservations

• 40 sites (not including Alternates and Ships)40 sites (not including Alternates and Ships)

• One launch per day!One launch per day! … … (minimal requirement)(minimal requirement)

• 2 (or 3) operational (NOAA and METOP ...) satellites2 (or 3) operational (NOAA and METOP ...) satellites– 15 (or 10) observations per satellite, per site, per month15 (or 10) observations per satellite, per site, per month– over 600over 600 (or 400)(or 400) observations globally, per satellite, per month observations globally, per satellite, per month– over 6000over 6000 (or 4000)(or 4000) observations globally, per satellite, per year observations globally, per satellite, per year

• COST:COST:– $ 5 million $ 5 million (… @ $300 per sonde ) (… @ $300 per sonde )

SHIPSSHIPS

The NOAA science vessel RHB provides radiosonde launch, insitu measurement, cloud observation and polar satellite direct receipt capabilities … an optimal platform for SUAN demonstration / support !

At about $250 per raob, twice per day, 250 days per year, estimated SUAN support is $125K yearly; very cost effective at fraction of RHB and NOAA polar program budget …

WHY WHY SUANSUAN ? ?

• Operational polar satellite Operational polar satellite – Measurements/Products require (Measurements/Products require (long-termlong-term) “scientific” ) “scientific”

Monitoring/Tuning … Monitoring/Tuning … using collocated radiosonde and using collocated radiosonde and satellite observations satellite observations

• Radiative TransferRadiative Transfer (RT) models(RT) models– require coincident T, H20 and Radiometric profiles require coincident T, H20 and Radiometric profiles – ““key to absolute accuracy” !?key to absolute accuracy” !?

• GlobalGlobal RadiosondesRadiosondes – ““can” provide necessary ground truth data, but have can” provide necessary ground truth data, but have

problems … problems …

• Standard Baseline Dataset Needed (since 1979 …)Standard Baseline Dataset Needed (since 1979 …)– currently available collocated radiosonde and satellite currently available collocated radiosonde and satellite

observations are observations are Not AdequateNot Adequate

Global Global RadiosondesRadiosondes

June 17-19 2003

Satellite and Radiosonde CollocationsSatellite and Radiosonde Collocations (Radiosondes launched within 1 hour “prior” to satellite overpass)(Radiosondes launched within 1 hour “prior” to satellite overpass)

Operational Satellite and Radiosonde Operational Satellite and Radiosonde Collocations Collocations (+/- 5hrs sea, +/- 3hrs land; 100km)(+/- 5hrs sea, +/- 3hrs land; 100km)

(Satellite – Radiosonde) Temperature statistics

Tropical land (30N to 30S)

June 7-14, 2003

Results “skewed” by regional sampling differences

NOAA-17

NOAA-16

NOAA-15

60N to 60S

60N to 60S Moisture

SUANSUAN Minimizes “ Minimizes “ArtificialArtificial” (not Same-” (not Same-Same)Same) Sampling Related Errors to Sampling Related Errors to Better Monitor “Better Monitor “RealReal” Sensor and Product ” Sensor and Product Performance/Uncertainty Performance/Uncertainty

RT ModelsRT Models• Critical for Cross-validation of Satellite, Critical for Cross-validation of Satellite,

Radiosonde, Climate and NWP DataRadiosonde, Climate and NWP Data

• Require consistent, reliable and robust Require consistent, reliable and robust collocations in support of R & D, validation collocations in support of R & D, validation

• Are “Are “Key”Key” to ascertaining absolute accuracy … to ascertaining absolute accuracy … resolve calculated (from Raob) vs observed resolve calculated (from Raob) vs observed (from satellite) radiance … ((from satellite) radiance … (and climate retrieval and climate retrieval problem)problem)

• SUAN sites optimal in support of long-term SUAN sites optimal in support of long-term RT model validation and development … RT model validation and development …

AMSU Sounding AMSU Sounding Channels Channels

AMSU-B at 183 +/- 1 gHz (upper troposhere moisture)

12-hour time composites

Adjustments are regressed from collocated satellite and radiosonde data

Magnitude and inter-satellite variability “skewed” by systematic radiosonde sampling differences,

NOAA-17

NOAA-16

NOAA-15

RT Bias Adjustments

RadiosondesRadiosondes

• Satellite radiometers can serve as transfer standard Satellite radiometers can serve as transfer standard for radiosonde monitoring via RT (McMillin et.al. 1988)for radiosonde monitoring via RT (McMillin et.al. 1988)

• SUAN sites would provide: SUAN sites would provide: – validating radiosondes validating radiosondes (intersonde experiments, non-SUAN, (intersonde experiments, non-SUAN,

......) ) – deriving radiation and inter-sonde “corrections” deriving radiation and inter-sonde “corrections” – demonstration of new technologies (ie, upper demonstration of new technologies (ie, upper

tropospheric moisture, drop-sondes …)tropospheric moisture, drop-sondes …)– balloon drift and local weather impactsballoon drift and local weather impacts– otherother

• Radiometer Sensor BiasRadiometer Sensor Bias– Systematic per satellite Systematic per satellite – Sensor response changesSensor response changes– Satellite drift Satellite drift

• Science BiasScience Bias– RT modelRT model– Processing Approach Processing Approach

• Measurement vs Derived ProductMeasurement vs Derived Product• TuningTuning

Climate ApplicationsProblems Include:

End Result: Uncertainty Outweighs the Signal (Seidel et al., 2004, Christy …)

Climate Applications Climate Applications FormulaFormula

“Real-time”“Real-time” Database Compilation Database Compilation EffortEffort …satellite data, ground truth collocations …satellite data, ground truth collocations …… (during satellite operational lifetime)(during satellite operational lifetime) to serve as input for to serve as input for

“Retrospective” Processing Effort “Retrospective” Processing Effort …T, H2O, Clouds, Measurements ...…T, H2O, Clouds, Measurements ... (at conclusion of satellite operational (at conclusion of satellite operational lifetime)lifetime)

SUAN can provide “long-term” records which “anchor” satellite and radiosonde performance (over time) for more effective utilization in retrospective climate applications …

Radiosonde and TOVS-1b History from Radiosonde and TOVS-1b History from 1979 1979 … … ((correcting the pastcorrecting the past …) …)

• GTS Radiosondes … (GTS Radiosondes … (NCEP, ERA-40, IGRANCEP, ERA-40, IGRA…)…)• Special Field Experiment Radiosondes:Special Field Experiment Radiosondes:

– ARMARM– JOSS (NCAR)JOSS (NCAR)– SHIPSSHIPS– Other ?Other ?

• TOVS Historical 1b-level dataTOVS Historical 1b-level data

• Goals:Goals:– Relational Data Base of Collocations, Directories, Relational Data Base of Collocations, Directories,

Metadata ...Metadata ...– TOVS , ATOVS … make operationalTOVS , ATOVS … make operational– Reprocess TOVS for Climate !!!Reprocess TOVS for Climate !!!

• Costly and time consuming processCostly and time consuming process– Ongoing “Arctic” NOAA-SEARCH (w/ Francis) Ongoing “Arctic” NOAA-SEARCH (w/ Francis)

http://www.orbit.nesdis.noaa.gov/smcd/opdb/poes/polarsearchhttp://www.orbit.nesdis.noaa.gov/smcd/opdb/poes/polarsearch– looking for fundinglooking for funding

BENEFITSBENEFITS • Monitor/Quantify Monitor/Quantify Satellite Measurement and Derived Satellite Measurement and Derived

ProductProduct Error/Accuracy/Uncertainty ( Error/Accuracy/Uncertainty (ATOVS … NPP ... ATOVS … NPP ... METOP ... NPOESS …) METOP ... NPOESS …)

• Monitor/Quantify Monitor/Quantify RT Model RT Model Error/Accuracy/UncertaintyError/Accuracy/Uncertainty

• Monitor/Quantify Monitor/Quantify RadiosondeRadiosonde (and in-situ)(and in-situ) Error/Accuracy/Uncertainty Error/Accuracy/Uncertainty

• ““Long-term” Long-term” PerformancePerformance Record Record

• Positive Impacts on Climate and NWP Positive Impacts on Climate and NWP

EXTRAS

Ongoing ActivitiesOngoing Activities

• New WMO Working Group under AOPC to New WMO Working Group under AOPC to address GUAN future and network design …. address GUAN future and network design …. Peter Thorne chairPeter Thorne chair

• NOAA Workshop … improve quality of future NOAA Workshop … improve quality of future upper air observations for climate upper air observations for climate (Seidel/Murray) :(Seidel/Murray) :– Phase-1 :Phase-1 : Winter 2005 to define Winter 2005 to define

requirementsrequirements– Phase-2 :Phase-2 : Spring 2005, potential networks Spring 2005, potential networks

and deployments to meet requirementsand deployments to meet requirements– Phase-3 :Phase-3 : Summer 2005, definition of Summer 2005, definition of

integrated observing system integrated observing system

• TOVS 1b-level and radiosonde collocations TOVS 1b-level and radiosonde collocations since 1979since 1979

Primary SUAN Primary SUAN CandidatesCandidates

SATELLITE COLLOCATIONS (+/- 3hrs, land; +/- 5hrs, sea)SATELLITE COLLOCATIONS (+/- 3hrs, land; +/- 5hrs, sea)

(used operationally at NESDIS)(used operationally at NESDIS)

Calculated (from RT) minus Observed AMSU-A measurements for channels 4 through 14 (NOAA-16) over Land, Ice and Snow, Coastal, and Sea terrains

SATELLITE COLLOCATIONS (+/- 3hrs, land; +/- 5hrs, sea)SATELLITE COLLOCATIONS (+/- 3hrs, land; +/- 5hrs, sea)

(used operationally at NESDIS)(used operationally at NESDIS)

VIZ B to Vaisala (RS80) at Chuuck Island

Satellites canserve as transfers standards to monitor radiosondes

Collocated Radiosonde and Satellite Observations provide basis for the

Monitoring Validating and Tuning

of Operational Satellite Data Systems

(… critical for climate retrieval problem)

Radiosonde and TOVS-1b Collocation Radiosonde and TOVS-1b Collocation History from 1979 (History from 1979 (… … correcting the pastcorrecting the past …)…)

• Costly and time consuming processCostly and time consuming process– Pending FY-05 “GCC” proposal (w Pending FY-05 “GCC” proposal (w

Goldberg, Thorne)Goldberg, Thorne)– Ongoing NOAA-SEARCH (w/ Francis) Ongoing NOAA-SEARCH (w/ Francis)

• GTS Radiosondes … (NCEP, ERA-40, IGRA…)GTS Radiosondes … (NCEP, ERA-40, IGRA…)• Special Field Experiment Radiosondes:Special Field Experiment Radiosondes:

– ARMARM– JOSS (NCAR)JOSS (NCAR)– SHIPSSHIPS– Other ?Other ?

• TOVS historical 1b-levelTOVS historical 1b-level datadata

• Goals:Goals:– Relational Data Base of Collocations, Relational Data Base of Collocations,

Directories, Metadata ...Directories, Metadata ...– TOVS , ATOVS … operationalTOVS , ATOVS … operational– Useful for ClimateUseful for Climate

Accuracy Statistics vsAccuracy Statistics vs RadiosondesRadiosondes ((Guess (light)Guess (light) vs vs Retrieval (heavy)Retrieval (heavy)))

Tuning to ErrorsTuning to Errors

Clear Cloudy

Collocations provide independent validation (heavy)and tuning (light)per satellite

NOAA-16(60N to 60S)

NWPNWP• Significant positive impact of satellite Significant positive impact of satellite

data on NWP reported over last 5 years data on NWP reported over last 5 years (McNally et.al. 2000, etc)(McNally et.al. 2000, etc)

• Associated NWP-based adjustment of Associated NWP-based adjustment of incoming satellite data (“cooking”) may incoming satellite data (“cooking”) may include systematic NWP error (Reale, include systematic NWP error (Reale, 1995, 2001, 2002) 1995, 2001, 2002)

• SUAN can potentially segregate such SUAN can potentially segregate such errors … errors …

SUAN can provide an NWP independent platform for “bias tuning”

leading to improved satellite data impact in frontal zones?

• Attempts to use 20+ years of TOVS (MSU) yield no Attempts to use 20+ years of TOVS (MSU) yield no meaningful overlap (Christy et.al, Mears et.al, Vinnikov and meaningful overlap (Christy et.al, Mears et.al, Vinnikov and Grody; 2003)Grody; 2003)

• Conclude that “uncertainties” inherent in historical satellite Conclude that “uncertainties” inherent in historical satellite and radiosonde data make them unsuitable for detecting and radiosonde data make them unsuitable for detecting long-term trends (Seidel et.al, 2004) long-term trends (Seidel et.al, 2004)

ClimateThe Problem:

SUAN can provide optimal data sets for maintaining the “long-term” records of satellite and radiosonde performance necessary to effectively utilize them in climate applications.

GUAN Sites GUAN Sites