gps tec measurements utilized for monitoring...
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GPS TEC Measurements Utilized for Monitoring Recent Space Weather
Events and Effects in Europe
GPS TEC Measurements Utilized for Monitoring Recent Space Weather
Events and Effects in EuropeS. M. Stankov (1) , N. Jakowski (2) , B. Huck (3)
(1) German Aerospace Center (DLR) – Institute of Communications and Navigation, D-17235 Neustrelitz, Germany(2) Allsat network+services, D-30159 Hannover, Germany
Presented at the 2nd European Space Weather Week, ESWW-2005, 14-18 November 2005, ESTECSession 3 (Ionosphere - positioning and telecommunication), 16 November 2005
Splinter Session (Recent space weather events and space weather services performance)
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OutlineOutline
Ground and space based GNSS observations –the German Aerospace Center (DLR) experienceGround and space based GNSS observations –the German Aerospace Center (DLR) experience
Generation of ionospheric disturbances –the importance of polar TEC monitoring
Generation of ionospheric disturbances –the importance of polar TEC monitoring
Propagation of ionospheric disturbances –TEC monitoring (Europe)
Propagation of ionospheric disturbances –TEC monitoring (Europe)
Propagation of ionospheric disturbances –case and statistical storm studies
Propagation of ionospheric disturbances –case and statistical storm studies
Adverse effects on GNSS reference network operationscaused by ionospheric disturbances
Adverse effects on GNSS reference network operationscaused by ionospheric disturbances
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DLR ionosphere observation experienceDLR ionosphere observation experience
Radio Occultation (IRO)
Ground-based observations
Space-based observations
GPS TEC + Ionosonde databased profile reconstruction
Data Assimilation
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Major Space Weather Events in 2005Major Space Weather Events in 2005
2121--26 Jan 200526 Jan 2005
0909--15 Sep 200515 Sep 2005
1515--20 May 200520 May 2005
2424--30 Aug 200530 Aug 2005
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Generation of ionospheric disturbances – the importance of polar TEC observationsGeneration of ionospheric disturbances – the importance of polar TEC observations
29 - 31 October 2003
Close correlation betweenTEC value behaviourand IMF southward component behaviour
IMF
/ nT
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Polar TEC observationsPolar TEC observations21 Jan 200521 Jan 2005 15 May 200515 May 2005
24 Aug 200524 Aug 2005 10 Sep 200510 Sep 2005
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European TEC observationsEuropean TEC observations21 Jan 200521 Jan 2005 22 Jan 200522 Jan 2005
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European TEC observationsEuropean TEC observations15 May 200515 May 2005 16 May 200516 May 2005
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European TEC observationsEuropean TEC observations24 Aug 200524 Aug 2005 25 Aug 200525 Aug 2005
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European TEC observationsEuropean TEC observations10 Sep 200510 Sep 2005 15 Sep 200515 Sep 2005
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25 J
uly
2004
25 J
uly
2004
GNSS reference network integrity during ionospheric disturbancesGNSS reference network integrity during ionospheric disturbances
REFERENCE NETWORK MODEL INTEGRITYREFERENCE NETWORK MODEL INTEGRITYREFERENCE NETWORK MODEL INTEGRITY
Non-linear Error
Estimation:
. ionospheric influence on GNSS signals determined;
. linear parts of these effects removed by applying ionospheric and geometric corrections;
. influence on user position is interpolated from the influence determined on surrounding reference stations;
. predicted error is compared with measured values and ionospheric and geometric errors are estimated.
Non-linear Error
Estimation:
. ionospheric influence on GNSS signals determined;
. linear parts of these effects removed by applying ionospheric and geometric corrections;
. influence on user position is interpolated from the influence determined on surrounding reference stations;
. predicted error is compared with measured values and ionospheric and geometric errors are estimated.
Erro
r [m
]
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GNSS reference network integrity and TEC measurementsGNSS reference network integrity and TEC measurementsEr
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Latitude Gradient Index
The latitudinal gradient index (at high latittudes) is correlated with the (relative) residual error in GPS reference networks and therefore, with thenetwork model integrity/performanceThe latitudinal gradient index is a potential toolfor forecasting problems in GNSS referencenetworks, e.g. increased time to fix ambiguities
60°N
40°N
7 November 20047 November 2004
GNSS reference network integrity and TEC measurementsGNSS reference network integrity and TEC measurements
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DLR Operational Space Weather Service - IonosphereOperational provision of GPS dataPre-processing and calibrationGeneration of TEC mapsand derivativesDevelopment of forecast modelsPost-processing and analysis of space weather effectsAnalysis of benefit for service users
http://www.kn.nz.dlr.de/swippa/index.htm
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GPS / GLONASS stationsGPS / GLONASS stations
ascos reference networkascos reference network
6 sub networks6 sub networks
35 stations used35 stations used
RINEX formatRINEX format
DLR Operational Space Weather Service – Ionosphere / GNSS Reference NetworkDLR Operational Space Weather Service – Ionosphere / GNSS Reference Network
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DLR Operational Space Weather Service – Ionosphere / TEC ProductsDLR Operational Space Weather Service – Ionosphere / TEC Products
TECTEC
latitudinal gradients
latitudinal gradients
longitudinal gradients
longitudinal gradients
temporalgradientstemporalgradients
18 Jan 200518 Jan 2005 50°N ,12.5°E
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DLR Space Weather Service and SWENET (Space Weather European Network)DLR Space Weather Service and SWENET (Space Weather European Network)
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Summary and OutlookSummary and Outlook
Pronounced seasonal and latitudinal differences in ionospheric storm generation/developmentPronounced seasonal and latitudinal differences in ionospheric storm generation/development
Positive ionospheric storms – more frequent and much stronger during winter Positive ionospheric storms – more frequent and much stronger during winter
Ionospheric irregularities - higher frequency during night and higher intensity during winterIonospheric irregularities - higher frequency during night and higher intensity during winter
TEC – basic parameter for monitoring the ionospheric storm generation and propagationTEC – basic parameter for monitoring the ionospheric storm generation and propagation
Permanent combined ground- and space- based observations of several ionospheric parameters – the key to understanding space weather / ionosphere storm effects and their predictionPermanent combined ground- and space- based observations of several ionospheric parameters – the key to understanding space weather / ionosphere storm effects and their prediction
Operational space weather / ionosphere monitoring is requiredin present-day GNSS-based precise positioning services
Operational space weather / ionosphere monitoring is requiredin present-day GNSS-based precise positioning services
High resolution mapping – absolutely necessary if small-scale phenomena are targetedHigh resolution mapping – absolutely necessary if small-scale phenomena are targeted
Space Weather Warnings / Alerts – optimal update rate: 5 minSpace Weather Warnings / Alerts – optimal update rate: 5 min
TEC (and derivatives) mapping - optimal resolution: spatial - 1 deg, time - 5 minTEC (and derivatives) mapping - optimal resolution: spatial - 1 deg, time - 5 min
Positive feedback from end users / customersPositive feedback from end users / customers
Requirements for even higher resolution products and user friendly servicesRequirements for even higher resolution products and user friendly services