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Outline How do we define space weather? How do we observe it? What drives it (solar activity and solar phenomena)? Which are the impacts on: the atmosphere and technological sysytems? How can we forecast it? What service exist? Today’s space weather.
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The Sun Diameter: 1 390 000 km (109 x Earth) Mass: 1.99x10 30 kg (330 000 x Earth) Density: Core 151x10 3 kg/m -3 Average 1.41 x10 3 kg/m -3 The Sun consits of: H (≈ 90%) Helium (≈ 10%) C,N,O ( ≈ 0.1%) Temperature: Core 15 million Photosphere 5800 K Chromosphere 4300- 10 4 K Corona 1-30 million K 4 protons --> He + 2 positrons + 2 neutrinos + 2 fotons (26.2 MeV)
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When the solar magnetic field emerges thru the solar suface sunspots appear
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Chromosphere Prominence Solar flare The chromosphere in H-alpha
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TRACE
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The solar corona seen at solar eclipses
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The heating of the solar corona
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Coronal mass ejections
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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
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Solar flares and sun quakes
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The solar wind Predicted from comet studies in 1940 ties Theoretically predicted by Parker 1959 Measusred in situ 1960
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The source of the fast solar wind
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Solar wind Typical values V: 450km/s N: 5particles/cm 3 T: 10 5 K B: 5nT The solar wind consists of protons, electrons and 3-4% alpha particles
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Computation of the coronal magnetic field Daily observations of the solar photospheric magnetic field at WSO are used for computation of the coronal magnetic field according to the ”potential field model”.
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Computed Br at R=2.5Rs
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The heliospheric current sheet
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Fast continuous solar wind from coronal holes The solar wind Fast halo CME with solar flares and solar proton events Heliospheric current sheet The solar wind Bz, V, and n determine the effect of the solar plasma.
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Earth’s response Geomagnetic disturbances Aurora Ionospheric disturbances Climate and weather changes
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Earth’s magnetosphere and current systems
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Geomagnetic storms
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Earth’s magnetosphere and ionosphere
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Aurora oval
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The aurora observed in Stockholm Aurora was observed in Italy 6-7 April and on July 15-16, 2000! Aurora during severe solar storms
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Space weather effects on technological systems
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Satellite anomalies
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Satellite anomalies of July 14-16, 2000 event The proton event caused problems for ACE, SOHO, Ørsted, Japanese X-ray satellite, star trackers on board commercial satellites. Proton flux (pfu) > 10 MeV, 24000 pfu (July 15, 12.30 UT). Third largest! Largest 43 000 pfu, (March 24, 1991). Second 40 000 pfu (October 20, 1989).
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Solar proton events are dangerous to man in space Between Apollo 16 and 17 a proton event occurred, which should have been deadly to the astronautes within 10 hours (i.e. above 4000 mSv). Mars
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Radiation risks and aviation The radiation exposure is doubled every 2.2 km. Solar flares can increase the radiation by 20- 30 times. Pilots get cancer more often than average. New EU law: Pregnant (aircrew) should not be exposed to more than 1 (1-6) millisievert/year The intensive solar flare of April 2, 2001, which caused major communication problems also made Continental Airlines to change their route between Hong Kong and New York.
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Power systems are effected at times of geomagnetic storms This severe electrojet caused the failure of Quebec’s power system March 13-14, 1989. One of the generators of OKG’s (Sydkraft’s) nuclear plants was heated due to the geomagnetically induced current in March 13-14 1989. A transformer damaged in Main USA.
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Workshops arranged by us Workshops on ”Artificial Intelligence Applications in Solar-Terrestrial Physics” were held in Lund 1993 and 1997.
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Artificial neural networks The basic element of every ANN is an artificial neuron or simply a neuron (which is an abstract model of a biological neuron (nerve cell)).
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Download Lund Dst model in Java and Matlab The ARMA filter is obtained by adding auto-regressive terms to a MA filter.The partial recurrent network (Elman) becomes identical to a linear ARMA filter if it is assigned linear activations functions.
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Our scientific approach
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Real-time test of Dst forecasts
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Test Dst forecasts
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Applications Input parametersOutputKBNM method Reference Daily sunspot number SOM and MLP Liszka 93;97 Monthly sunspot numberDate of solar cycle max and amplitude MLP and Elman Macpherson et al., 95, Conway et al, 98 Monthly sunspot number and aa Date of solar cycle max and amplitude ElmanAshmall and Moore, 98 Yearly sunspot numberDate of solar cycle max and amplitude MLPCalvo et al., 95 McIntosh sunspot class & MW magn complex. X class solar flareMLP expert system Bradshaw et al., 89 Flare location, duration X-ray and radio flux Proton eventsMLPXue et al., 97 X-ray fluxProton eventsNeuro- fuzzy system Gabriel et al., 00 Photospheric magnetic field expansion factor Solar wind velocity 1-3 days ahead RBF & PF MHD Wintoft and Lundstedt 97;99
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Applications Input parametersOutputKBNM method Reference Solar wind n, V, BzRelativistic electrons in Earth magnetosphere hour ahead MLPWintoft and Lundstedt, 00 Solar wind n,V, Bz, Dst Relativistic electrons one hour ahead MLP, MHD, MSFM Freeman et al., 93 Kp Relativistic electrons day ahead MLPStringer and McPherron, 93 Solar wind V from photospheric B Daily geomagnetic Ap index MLPDetman et al., 00 Ap index MLPThompson, 93 Solar wind n, V, BzKp index 3 hours aheadMLPBoberg et al., 00 Solar wind n, V, B,Bz Dst 1-8 hours aheadMLP, ElmanLundstedt, 91; Wu and Lundstedt, 97 Solar wind n, V, B,Bz AE 1 hour aheadElman, MLPGleisner and Lundstedt,00,Gavrishchaka et al.,00, 01
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Applications Input parametrsOutputKBNM methodReferences Solar wind V 2 B s, (nV 2 ) 1/2, LT, local geomag x e, Y w Local geomagnetic field X, Y MLP and RBFGleisner and Lundstedt 00 Solar wind n,V, BzNone, weak or strong aurora MLPLundstedt et al., 00 foF2foF2 1 hour aheadMLPWintoft and Lundstedt, 99 AE, local time, seasonal information foF2 1-24 hours ahead MLPWintoft and Cander, 00 foF2, Ap, F10.7 cm24 hours aheadMLPWintoft and Cander, 99 Kp Satellite anomaliesMLPWintoft and Lundstedt 00 Solar wind n, V, BzdBx/dt, GICElman, MLPKronfeldt et al., 01 and Weigel et al.,02
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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 1-3 days ahead possible. Solar input data
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ESA/Lund Space Weather Forecast Service Package
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Near and farside solar activity from MDI/SOHO observations
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Latest information on arrival of halo CME at L1
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Latest info on forecasts of satellite anomalies (SAAPS)
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Latest information on forecasts of Kp, Dst, AE and GIC
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Our GIC Pilot Project An application at implementation stage
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Today general forecast service is given by RWCs within ISES ISES Director: D. Boteler Deputy Director: H. Lundstedt Secr. for World days: H. Coffey Secr. Space Weather: J. Kunches WWW for Satellites: J. King
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RWC - Sweden ISES
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The October 14 -November 6 events: It all started with no sunspots No sunspots (R=24) Aurora observed in Southern Sweden (Gothenburg, Lund) Media got interested SOHO/MDI far side images had told me Large ARs were to come
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Many radio and newspaper interviews followed and AR 484 entered
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Then came the AR 486, October 28 event Even more interviews Warnings and reports were sent to power industry Discussions with power operators
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Power outage in Malmö Rz spectral density LF 20-128 days. Stora AR vanligare. Power Outage in Southern Sweden, October 30, 2003
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The power failure got enormous media attention in Sweden Every TV, radio station and newspaper had something
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And then ….X28 solar flare on November 4!!
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Active Regions 484/486/488 one rotation later
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Today’s Space Weather
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Where to learn more? www.lund.irf.se
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END Part 2 Acknowledgements. I am grateful to the following providers of images and animations; ESA/NASA SOHO teams.
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