5 th European Space Weather Week, 17-21 November 2008, Brussels Operational implementation of the...
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Transcript of 5 th European Space Weather Week, 17-21 November 2008, Brussels Operational implementation of the...
5th European Space Weather Week, 17-21 November 2008, Brussels
Operational implementation of the SWIF model in DIAS system
Tsagouri Ioanna
Koutroumbas Konstantinos
Belehaki Anna
National Observatory of Athens
5th European Space Weather Week, 17-21 November 2008, Brussels
DIAS system: Operational since August 2006 (http://dias.space.noa.gr) Developed under the eContent Programme of the European Commission
)
To develop and provide ionospheric products and services in real-time, and thus to fully characterise the ionospheric conditions over European middle latitudes.
5th European Space Weather Week, 17-21 November 2008, Brussels
IonogramsF-plot: nowcasting foF2
F-plot: forecasting foF2
SSN daily plotMUF Point to PointfoF2 Map NowcastingM(3000)F2 Map
NowcastingMUF Map NowcastingNe Map Nowcasting
5th European Space Weather Week, 17-21 November 2008, Brussels
DIAS users: more than 100 registered users
SectorDefence Industry
Aviation Industry
Civil HF broadcast
Amateur radio
Upper atmosphere researchers
DIAS users’ requirements survey reveals strong interest in receiving:
•Short term forecasts for prediction step more than 1h ahead
•Alerts and warnings
5th European Space Weather Week, 17-21 November 2008, Brussels
DIAS forecasting products
TSAR: Time Series AutoRegressive technique for short term prediction of the foF2 (Koutroumbas et al., 2008)
GCAM: Geomagnetically Correlated Autoregression Model for short term prediction of foF2 (Muhtarov et al., 2002)
5th European Space Weather Week, 17-21 November 2008, Brussels
Further improvements • Issuing alerts and warnings for forthcoming ionospheric disturbances over Europe• Upgrade of TSAR for storm conditions
Athens 15min ahead
1h ahead
3h ahead
6h ahead
Pruhonice
5th European Space Weather Week, 17-21 November 2008, Brussels
SWIF: Solar Wind driven autoregression model for Ionospheric short term ForecastIonospheric forecasts up to 24 h ahead as well as alerts and warnings
TSAR: Time Series AutoRegressive technique that provides ionospheric forecasts up to 24 h ahead under all possible geophysical conditions (Koutroumbas et al., 2008)
foF2 current and recent past values
STIM: Empirical Storm Time Ionospheric Model that formulates the ionospheric storm time response in respect to IMF disturbances (Tsagouri and Belehaki, 2008) Reference
foF2 values and IMF parameters from ACE
5th European Space Weather Week, 17-21 November 2008, Brussels
STIM is triggered by an alert signal for upcoming ionospheric storm-time disturbances obtained by the analysis of IMF observations from ACE.
STIM (Tsagouri and Belehaki, JASTP, 2008)
The idea: Use as “driver” the solar wind magnetic field at L1 contributing to the forecast of the high latitude Joule heating at least one hour in advance.
5th European Space Weather Week, 17-21 November 2008, Brussels
Crucial parameters:
B
dB/dt
IMF-Bz orientation
The alert provides the IMF disturbance onset at L1 point some hours in advance.
Bmag
dB/dt
Bz
Dst
foF2obs/foF2median
Determination of alert conditions based on IMF observations
5th European Space Weather Week, 17-21 November 2008, Brussels
i) The IMF-B should record either a rapid increase (3.8 nT/h) or absolute values greater than 13 nT. ii) The IMF-Bz component should be southward directed (Bz < - 10 nT for at least three hours) either simultaneously or a few hours later (maximum 5 hours later). iii) Each event ends when Bz is turned northward (Bz > -1 nT).
5th European Space Weather Week, 17-21 November 2008, Brussels
TSAR provides successful predictions 1h ahead
for prediction steps greater than 1h ahead, STIM’s performance is systematically more successful than TSAR’s
Comparative evaluation of TSAR’S and STIM’s predictions
5th European Space Weather Week, 17-21 November 2008, Brussels
SWIF modelSWIF model
Alert Detection Algorithm (ADA)Alert Detection Algorithm (ADA)
ACE Real-time data
ACE Real-time data
No Alert(Quiet Conditions)
No Alert(Quiet Conditions)
Alert(Forthcoming storm conditions)
Alert(Forthcoming storm conditions)
Short Term Predictions issued by: TSAR
Short Term Predictions issued by: TSARTSAR algorithmTSAR algorithm Short Term Predictions issued by:
TSAR (1 hour after the ADA)STIM (more than 1 hour after the ADA until 24 hr after the end of storm disturbance)
Short Term Predictions issued by:TSAR (1 hour after the ADA)STIM (more than 1 hour after the ADA until 24 hr after the end of storm disturbance)
STIM algorithmSTIM algorithm
SWIF Short Term PredictionsSWIF Short Term Predictions
Historical and real-time data from Ionospheric
Station
Historical and real-time data from Ionospheric
Station Local Time in the station location
Local Time in the station location
5th European Space Weather Week, 17-21 November 2008, Brussels
Evaluation tests Over 10 storm events
Middle to high latitudes, Storm conditions
0
20
40
60
80
100
120
3 h ahead 6 h ahead 12 h ahead 24 h ahead
Prediction step (hours ahead)
Rel
ativ
e im
prov
emen
t (%
)
Juliusruh Chilton
Middle to low latitudes, Storm conditions
0
20
40
60
80
100
120
3 h ahead 6 h ahead 12 h ahead 24 h ahead
Prediction step (hours ahead)
Rel
ativ
e im
pro
vem
ent
(%)
Athens Rome
Middle to low latitudes, Post storm conditions
0
20
40
60
80
100
120
3 h ahead 6 h ahead 12 h ahead 24 h ahead
Prediction step (hours ahead)
Rel
ativ
e im
pro
vem
ent
(%) Athens Rome
Middle to high latitudes, Post-storm conditions
0
20
40
60
80
100
120
3 h ahead 6 h ahead 12 h ahead 24 h ahead
Prediction step (hours ahead)
Rel
ativ
e im
prov
emen
t (%
)
Juliusruh Chilton
5th European Space Weather Week, 17-21 November 2008, Brussels
Comparison of SWIF’s – TSAR’s –GCAM’s (Muhtarov et al., 2002) performance
5th European Space Weather Week, 17-21 November 2008, Brussels
This along with the additional advantage of SWIF in providing alerts and warnings for forthcoming ionospheric disturbances make SWIF algorithm a powerful tool in the development of a full set of
ionospheric forecasting services.
Conclusions
We believe that the results presented here support SWIF’s potential efficiency in providing reliable ionospheric forecasts during all possible ionospheric conditions for operational applications.
5th European Space Weather Week, 17-21 November 2008, Brussels
Implementation of the SWIF algorithm to the DIAS related productsImplementation of the SWIF algorithm to the DIAS related products
Short term predictions for each station, in time plots and ASCII for Short term predictions for each station, in time plots and ASCII for 24 hours ahead;24 hours ahead;
European maps of foF2 for the next 24 hours based on SWIF European maps of foF2 for the next 24 hours based on SWIF predictions, calculated with the SIRMUP method;predictions, calculated with the SIRMUP method;
Upgraded of the European map of Ionospheric Disturbances Upgraded of the European map of Ionospheric Disturbances currently provided by DIAS with the accurate SWIF predictions;currently provided by DIAS with the accurate SWIF predictions;
Implementation of the SWIF alert detection algorithm in DIAS Implementation of the SWIF alert detection algorithm in DIAS system to issue storm alerts for Europe.system to issue storm alerts for Europe.
The upgrade is expected to be accomplished until March, 2009. The upgrade is expected to be accomplished until March, 2009.
Acknowledgements: This work is part of the EOARD grant FA 8655-07-M-4008