the solar and space weather reseach group in lund space weather solar activity - the driver...

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The Solar and Space Weather Reseach Group in Lund

The Solar and Space Weather Reseach Group in Lund

• Space weather• Solar activity - the driver• Modelling and forecasting

space weather and effects using KBN

• ESA/Lund Space Weather Forecast Service

• Regional Warning Center Sweden in Lund

• www.irfl.lu.se

Space weatherSpace weather

• The solar activity causes conditions that can influence the Earth’s atmosphere, technological systems, and endanger human health and life.

• We call that space weather

SOHOSOHO

• Solar Heliospheric Observatory was launched on December 2, 1995

• SOHO carries three instruments observing the solar interior, six the solar corona and three the solar wind

Stanford collaborationStanford collaboration

MDI/SOHO reveals the interiorMDI/SOHO reveals the interior

MDI shows how magnetic elements form sunspots

MDI shows how the dynamo changes

Sunspots are footpointsof emerging magnetic flux tubes

Sunspots observed on solar surface

Sunspots observed on solar surface

Schwabe found the 11- year sunspot solar cycle. R = k(10g + f)

The two peaks of solar activity, 1.3 years separated!

Gleissberg solar cycle in sunspot group number

Gleissberg solar cycle in sunspot group number

Gleissberg found an amplitude modulation of the 11-yearcycle of 80-90 years, as seen by the sunspot group number

High solar activity and warm climate, low and cold climateHigh solar activity and warm climate, low and cold climate

The solar activity during 5 000 yearsderived from C14 measurments in old trees.

Cold climate in England, Holland during Little Ice Age. Vikings settled down in Greenland during warm Middle Age.

Possible physical explanation of solar climate relation

Possible physical explanation of solar climate relation

The solar coronal magneticflux has increased with 131%since 1901.

High solar activityCosmic ray decreasesCloud coverage decreasesHigher temperature

Clouds effect climate 100 times more effectively than CO2.

Solar activity and North Atlantic Oscillation Index

Solar activity and North Atlantic Oscillation Index

CMEs cause the most severe space weather effects

CMEs cause the most severe space weather effects

• Halo CMEs are most geoeffective

• Mass: 5-50 billion tons

• Frequency: 3.5/day (max), 0.2/day (min)

• Speed: 200-2000 km/s

Early CME signal in wavelet power spectra of MDI data

Early CME signal in wavelet power spectra of MDI data

Wavelet power spectra of MDI magnetic mean field

Wavelet power spectra of MDI magnetic mean field

Upper panel shows for 53 CME events.Lower panel shows for times without CMEs.

Probing CMEs with a solar radarProbing CMEs with a solar radar

15 000 antennas with sensorsand emitters, organized in 100clusters distributed within acircular region of about 350 kmdiameter. Frequency 10-250 MHz(30-1.5m). The total data rate will be 2.5 Tbits/s.

Modelling and forecasting with KBN

Modelling and forecasting with KBN

• The basis of using neural networks as mathematical models is ”mapping”. Given a dynamic system, a neural network can model it on the basis of a set of examples encoding the input/output behavior of the system. It can learn the mathematical function underlying the system operation (generalize), if the network is properly designed (architecture, weights) and trained (learning algorithm).

• Both architecture and weights can be determined from differential equations which describe the causal relations between the physical variables (the solution of the diff equation is approximated with a RBF). The network (KBN) is then trained with observations.

• The architecture (number of input and hidden nodes) can also be determined from dynamic system analysis (reconstruction of attractor from time series gives dimension).

• Neural network can discover laws from regularities in data (e.g. Newton’s law). If one construct a hierachy of neural networks where networks at each level can learn knowledge at some level of abstraction, even more advanced laws can be dicovered.

Workshops arranged by usWorkshops arranged by us

Workshops on ”Artificial Intelligence Applications in Solar-Terrestrial Physics” were held in Lund 1993 and 1997.

Real-time forecasts and warnings based on KBN Real-time forecasts and warnings based on KBN

Solar wind observations with ACE make accurate forecasts 1-3 hours ahead possible.

Solar observations with SOHO make warnings 1-3days ahead possible.

Solar input data

ESA Space Weather Programme Study

ESA Space Weather Programme Study

ESA/Lund Space Weather Forecast Service

ESA/Lund Space Weather Forecast Service

Near and farside solar activity from MDI/SOHO observationsNear and farside solar activity from MDI/SOHO observations

Latest information on arrival of halo CME at L1

Latest information on arrival of halo CME at L1

Latest info on forecasts of satellite anomalies

Latest info on forecasts of satellite anomalies

Latest information on forecasts of Kp, Dst, AE and GIC

Latest information on forecasts of Kp, Dst, AE and GIC

Test Dst forecastsTest Dst forecasts

Neural network forecasts of Dst vs other methods

Neural network forecasts of Dst vs other methods

Regional Warning CentersRWC-Sweden in Lund

Regional Warning CentersRWC-Sweden in Lund

Forecasts of aurora as SMS or voice messages

Forecasts of aurora as SMS or voice messages

Where to learn more about usWhere to learn more about us

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