The Sun‘sinstruments for shaping space weather Improving...
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1 ESA Space Weather Workshop: ESA Space Weather Workshop: Developing a European Space Weather Developing a European Space Weather Service Network Service Network SWENET: Space Weather European SWENET: Space Weather European Network Network 3- 5 November 2003, ESTEC, Noordwijk 5 November 2003, ESTEC, Noordwijk Rainer Rainer Schwenn Schwenn Max Max- Planck Planck - Institut für Institut für Aeronomie Aeronomie Lindau, Germany Lindau, Germany Improving prediction of space weather disturbances – what is needed? The The Sun‘s Sun‘s instruments for shaping space weather instruments for shaping space weather Flares CMEs/Flares CMEs/Coronal Holes Let us inspect the the three branches Let us inspect the the three branches w.r.t. w.r.t. basic understanding basic understanding, prediction reliability prediction reliability, needs for the future needs for the future. . Visible light Visible light , EUV, X , EUV, X- rays rays, Gamma , Gamma- rays rays Physics Physics: Unclear Unclear , but under intense study but under intense study... ... Arrival: Arrival: Simultaneously Simultaneously Duration Duration : Minutes Minutes to to hours hours 1. 1. Electromagnetic radiation from flares Electromagnetic radiation from flares Effects Effects : Sudden heating Sudden heating of of the the Earth‘s Earth‘s upper upper atmosphere atmosphere Impacts: Impacts: * Radio * Radio communications disturbed communications disturbed , * Sudden satellite Sudden satellitedrag drag Needed Needed : * Fundamental * Fundamental research for understanding basic release research for understanding basic release mechanism mechanism , source source and and amount amount of of energy energy to to be released be released , * High time * High time resolution optical observations resolution optical observations of of flare onset flare onset , * Search for Search for „dormant volcanos dormant volcanos“ by by MDI MDI type measurements type measurements and and modelling modelling. 1. 1. Electromagnetic radiation from flares Electromagnetic radiation from flares Prediction accurracy Prediction accurracy: Timing Timing on time on time scales scales of of days days poor poor Location Location often foreseeable often foreseeable good good Magnitude Magnitude potential potential range range, for experts for experts fairly fairly good good Significance Significance wide range wide range , fairly fairly good good
Transcript of The Sun‘sinstruments for shaping space weather Improving...
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ESA Space Weather Workshop:ESA Space Weather Workshop:Developing a European Space Weather Developing a European Space Weather
Service NetworkService NetworkSWENET: Space Weather European SWENET: Space Weather European
NetworkNetwork33--5 November 2003, ESTEC, Noordwijk5 November 2003, ESTEC, Noordwijk
RainerRainer SchwennSchwennMaxMax--PlanckPlanck--Institut fürInstitut für AeronomieAeronomie
Lindau, GermanyLindau, Germany
Improving prediction of space weather disturbances –what is needed?
TheThe Sun‘sSun‘s instruments for shaping space weatherinstruments for shaping space weather
Flares CMEs /Flares CMEs/Coronal Holes
Let us inspect the the three branchesLet us inspect the the three branchesw.r.t.w.r.t. basic understandingbasic understanding,, prediction reliabilityprediction reliability ,, needs for the futureneeds for the future. .
Visible lightVisible light, EUV, X, EUV, X--raysrays, Gamma, Gamma--raysrays
PhysicsPhysics:: UnclearUnclear ,, but under intense studybut under intense study......Arrival:Arrival: SimultaneouslySimultaneouslyDurationDuration :: MinutesMinutes toto hourshours
1.1. Electromagnetic radiation from flaresElectromagnetic radiation from flares
EffectsEffects :: Sudden heatingSudden heating ofof thethe Earth‘sEarth‘s upper upper atmosphereatmosphere
Impacts:Impacts: * Radio* Radio communications disturbedcommunications disturbed ,,** Sudden satelliteSudden satellitedragdrag
NeededNeeded:: * Fundamental* Fundamental research for understanding basic release research for understanding basic release mechanismmechanism ,, sourcesource andand amountamount ofof energyenergy toto be releasedbe released ,,
* High time* High time resolution optical observationsresolution optical observations ofof flare onsetflare onset ,,** Search forSearch for „„dormant volcanosdormant volcanos““ byby MDIMDI type measurementstype measurements
andand modellingmodelling..
1.1. Electromagnetic radiation from flaresElectromagnetic radiation from flaresPrediction accurracyPrediction accurracy::
TimingTiming on timeon time scalesscales ofof days days poorpoorLocationLocation often foreseeableoften foreseeable goodgoodMagnitudeMagnitude potentialpotential rangerange,, for expertsfor experts fairlyfairly goodgoodSignificanceSignificance wide rangewide range ,, fairlyfairly goodgood
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PhysicsPhysics:: OnsetOnset stillstill unclearunclear,, particle acceleration under intense studyparticle acceleration under intense study......Arrival:Arrival: SomeSome 1010 minutesminutes to 1to 1 hour after optical detectionhour after optical detectionDurationDuration :: HoursHours toto daysdays
2. High2. High energy particles from flaresenergy particles from flares and CMEand CME shocksshocks
ElectronsElectrons,, protonsprotons andand other ions with energiesother ions with energiesofof fewfew 100 MeV, at100 MeV, at times several GeVtimes several GeV
** DamageDamage toto exterior satellite surfacesexterior satellite surfaces,, causing degradationcausing degradation of of solarsolar cellscells,, optical elementsoptical elements, etc.,, etc.,
** DamageDamage to solidto solid state devicesstate devices,, leadingleading toto malfunctionsmalfunctions ,, single single event upsetsevent upsets ,, latchupslatchups etc. inetc. in satellite electronicssatellite electronics,,
* Blinding of CCD* Blinding of CCD camerascameras in Earthin Earth orbitorbit ,,** Enhanced radiation doses for astronautsEnhanced radiation doses for astronauts,, particularly dangerous particularly dangerous
during EVAsduring EVAs..
2. High2. High energy particles from flaresenergy particles from flares and CMEand CME shocksshocks
EffectsEffects : : ** HeatingHeating andand ionizationionization ofof thethe Earth‘sEarth‘s upper atmosphereupper atmosphere, , ** ElectrificationElectrification ofof the upper stratospherethe upper stratosphere. .
Impacts:Impacts: * Radio* Radio communications disturbedcommunications disturbed ,,
NeededNeeded:: * Fundamental* Fundamental research for understanding basic mechanismresearch for understanding basic mechanism,,sourcesource andand amountamount ofof energyenergy toto be releasedbe released ,,
* ...* ... for understanding shock formationfor understanding shock formation andand propagationpropagation* ...* ... for understanding particle accelerationfor understanding particle acceleration* ...* ... for understanding particle propagationfor understanding particle propagation
2. High2. High energy particles from flaresenergy particles from flares and CMEand CME shocksshocksPrediction accurracyPrediction accurracy::
TimingTiming on timeon time scalesscales ofof daysdays // yearsyears poorpoor //very poorvery poorLocationLocation often foreseeableoften foreseeable goodgoodMagnitudeMagnitude potentialpotential rangerange,, for expertsfor experts fairlyfairly goodgoodSignificanceSignificance wide rangewide range ,, with surpriseswith surprises fairfair
Kaiser et al., 1998
Propagation of shock waves from the Sun towards EarthWhere and how are they accelerated/decelerated?Answers might come from radio wave observations,especially for improving space weather forecasts.
2. High2. High energy particles from flaresenergy particles from flares and CMEand CME shocksshocks
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NeededNeeded:: * High time* High time--resolution optical observationsresolution optical observations ofof flareflare/CME/CME onsetonset,,* Radio* Radio observationsobservations, in, in frequency range fromfrequency range from 100 MHz to 1 KHz.100 MHz to 1 KHz.
2. High2. High energy particles from flaresenergy particles from flares and CMEand CME shocksshocksInterplanetary shocksInterplanetary shocks,, magnetic cloudsmagnetic clouds,, plasma turbulence as plasma turbulence as
productsproducts ofof coronal mass ejectionscoronal mass ejections, all, all contributingcontributing toto generate generate geomagnetic stormsgeomagnetic storms..
3.3. LowLow to mediumto medium--energy particlesenergy particles,, plasma cloudsplasma clouds
PhysicsPhysics:: ** OriginOrigin ofof CMEs unclearCMEs unclear,, but under intense studybut under intense study. . ** Propagation is being modelledPropagation is being modelled ,, empirical approaches under empirical approaches under
developmentdevelopment. . Arrival:Arrival: afterafter 1 to 51 to 5 daysdaysDurationDuration :: hourshours toto daysdays
EffectsEffects : : ** Sudden compressionSudden compression ofof thethe Earth‘sEarth‘s magnetospheremagnetosphere, , ** DistortionDistortion andand depletiondepletion ofof the radiation beltsthe radiation belts,, leadingleading
toto releaserelease ofof large fluxeslarge fluxes ofof energetic particlesenergetic particles,,** InjectionInjection ofof plasma from magnetotail intoplasma from magnetotail into polarpolar
magnetospheremagnetosphere//ionosphereionosphere,, thus causing auroraethus causing aurorae,,** Severe disturbancesSevere disturbances of ringof ring currentscurrents, i.e., i.e. geomagnetic geomagnetic
stormsstorms , , ** HeatingHeating ofof ionosphereionosphereandand upper atmosphereupper atmosphere,,
3.3. LowLow to mediumto medium--energy particlesenergy particles,, plasma cloudsplasma clouds
** Strong fluctuationsStrong fluctuations ofof geomagnetic fieldgeomagnetic field,,* Radio* Radio communications disturbedcommunications disturbed ,,** Sudden satelliteSudden satellitedragdrag duedue toto heatingheating ofof the the
upper atmosphereupper atmosphere,,* Charge* Charge--up ofup of satellite surfaces duesatellite surfaces due to highto high
fluxesfluxes ofof energetic electronsenergetic electrons,,
3.3. LowLow to mediumto medium--energy particlesenergy particles,, plasma cloudsplasma clouds
Impacts:Impacts: * Bright* Bright auroraeaurorae ,, eveneven atat low latitudeslow latitudes,,
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Impacts:Impacts: ** Satellite damages from penetrating energetic particlesSatellite damages from penetrating energetic particles,,** Satellite disorientation dueSatellite disorientation due toto magnetic field distortionmagnetic field distortion,,** GICs endangeringGICs endangering powerpower distribution netsdistribution nets,, pipelinespipelines,,
telecommunication linestelecommunication lines etc, etc,
3.3. LowLow to mediumto medium--energy particlesenergy particles,, plasma cloudsplasma clouds
** EffectsEffects onon biologicalbiological systemssystems
Halo CMEs
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94 measured points, 102 total, unique CME-IP associationcurve fit: t = -22.75*ln(Vexp) + 220.8
R = -0.62 ; SD = 14.61
limb events
03.09.2001
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halo expansion speed (km/s)0 500 1000 1500 2000 2500 3000 3500
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95 events, 102 total, unique CME-IP associationcurve fit: t = -17.85*ln(Vfr) + 181.71R = -0.47 ; SD = 16.21
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halo front speed (km/s)
Front speed vs travel time Expansion speed v s travel time
Vexp
VprVfr
3.3. LowLow to mediumto medium--energy particlesenergy particles,, plasma cloudsplasma cloudsPrediction accurracyPrediction accurracy::
TimingTiming empirical modelsempirical models good, t.b.i.s.good, t.b.i.s.
Conclusions from recent studies of CME/ICME correlations
• A good correlation between vexpand the travel time to 1 AU was found from 102 events observed from 1997 to 2001.
• Measuring v exp for halo CMEs allows to predict their travel time to 1 AU.Ttr = 206.6 – 21.36 * ln (vexp) [hours].
• There is still substantial uncertainty, indicating that processe s occurring during the “trip” of theCMEs from the sun to 1 AU may play an important role.
• 7 out of 181 full front side halo CMEs never reach the earth –3.9% false alarms!
• 6 out of 145 transient shocks were not related to any CME –4.1 % shock predictions missed!
• 1 out of 30 intense storms and 4 out of 78 moderate storms were not related to any CME –
6 % storm prediction missed!• All very intense storms (Dst < -200 nT) were related to halo CMEs.
3.3. LowLow to mediumto medium--energy particlesenergy particles,, plasma cloudsplasma clouds 3.3. LowLow to mediumto medium--energy particlesenergy particles,, plasma cloudsplasma cloudsPrediction accurracyPrediction accurracy::
LocationLocation orientation often dubiousorientation often dubious fairfairMagnitude Magnitude surprisingly lowsurprisingly low fairfairSignificanceSignificance embarrasingly lowembarrasingly low poorpoor
NeededNeeded:: * Fundamental* Fundamental research for understanding basic research for understanding basic mechanismmechanism of CMEof CME releaserelease,,
* High time* High time resolution optical observationsresolution optical observations of CMEof CME onsetonsetandand propagationpropagation,, simultaneously fromsimultaneously from differentdifferent view view pointspoints (stereo(stereo viewview) ,) ,
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3.3. LowLow to mediumto medium--energy particlesenergy particles,, plasma cloudsplasma clouds
NeededNeeded:: * On* On--lineline computer modelcomputer model ofof the heliospherethe heliosphere,, continously continously updatedupdated,, that allowsthat allows toto simulatesimulateCMECME ejectionsejections andandpropagationpropagation inin realisticrealistic andand nearnear--realreal--time way.time way.
NeededNeeded:: ** Continuous surveyContinuous survey ((for CMEs propagating towardsfor CMEs propagating towards Earth) ofEarth) ofthethe EarthEarth--Sun lineSun line from distant spacecraftfrom distant spacecraft, e.g., STEREO,, e.g., STEREO,
** Continuous monitoringContinuous monitoring ofof filament helicitiesfilament helicities , in order to, in order torevealreveal potentialpotential magnetic cloud topologiesmagnetic cloud topologies ((Bz south whenBz south when?)?)earlyearly on. on.
3.3. LowLow to mediumto medium--energy particlesenergy particles,, plasma cloudsplasma clouds
Note how different the geomagnetic response is, despite the similarity of both: the cloud pattern and the Forbush decrease!
A SEN cloud at 1 AU A NES cloud at 1 AU
Storm Storm
Forbush decrease Forbush decrease
NeededNeeded:: * A* A dedicated spacecraftdedicated spacecraft at L1 (at L1 (or closeror closer toto thetheSun!),Sun!),carryingcarrying: : an EUV/Xan EUV/X--ray imagerray imager ofof thetheSun,Sun,a sensitivea sensitive coronagraphcoronagraph ,, for quantifying halo CMEsfor quantifying halo CMEs ,,aa complete setcomplete set ofof standard particlestandard particle andand field instrumentsfield instruments,,a MDIa MDI type instrumenttype instrument toto monitor themonitor the Sun‘ sSun‘ s interorinteror..
* A* A space weather warning centerspace weather warning center onon the groundthe ground ,, equipped equipped withwith realreal--timetime datadata linkslinks bothboth toto the spacecraftthe spacecraft inin orbitorbitand toand to the modelling computersthe modelling computers, to, to produce nearproduce near--realreal--timetimereports through thereports through theWebWeb
3.3. LowLow to mediumto medium--energy particlesenergy particles,, plasma cloudsplasma clouds
In order to avoid this:
PotentialPotential causescauses:: 1. 1. Long term variations in total irradiance (“total energy”)Long term variations in total irradiance (“total energy”)is is assumed to only explain part of the global warmingassumed to only explain part of the global warming..
2. 2. Long term variation in UV/EUV radiationLong term variation in UV/EUV radiation changeschangescchemistryhemistry (ozone(ozone!!), temperature etc. in the), temperature etc. in the Earth’s Earth’s atmosphereatmosphere..
3. 3. Long term variation in the Sun’s magnetic fieldLong term variation in the Sun’s magnetic fieldmodulates modulates galactic galactic cosmic rays and the solar windcosmic rays and the solar wind..
The Sun and global warmingThe Sun and global warming ofof thethe Earth?Earth?
Note:Note: since aboutsince about 19801980 mankindmankindandand its its
greenhouse effect took overgreenhouse effect took over !!
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Sigmoids?
•• How to predictHow to predict CMEsCMEs/flares before they /flares before they occur?occur?
Research topics for the future:Research topics for the future:
Two small comets were evaporating near the Sun.A few hours later a huge ejection occurred . Coincidence?
No, says Dan Baker!
Triggering CMEs?
Triggering CMEs?
• How to predict CMEs/flares before they occur?
• Topology evolution: from CMEs to interplanetary clouds?
?
Research topics for the future:Research topics for the future:
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•• How to predictHow to predict CMEsCMEs/flares before they /flares before they occur?occur?
•• Topology evolution: fromTopology evolution: from CMEsCMEs to to interplanetary clouds?interplanetary clouds?
•• How to predict How to predict geoeffectivenessgeoeffectiveness??
Research topics for the future:Research topics for the future:
Note how different the geomagnetic response is, despite the similarity of both: the cloud pattern and the Forbush decrease!
A SEN cloud at 1 AU A NES cloud at 1 AU
Storm Storm
Forbush decrease Forbush decrease
•• How to predictHow to predict CMEsCMEs/flares before they /flares before they occur?occur?
•• Topology evolution: fromTopology evolution: from CMEsCMEs to to interplanetary clouds?interplanetary clouds?
•• How to predict How to predict geoeffectivenessgeoeffectiveness??
•• Better modelsBetter models//observations of CME observations of CME propagation towards Earthpropagation towards Earth..
Research topics for the future:Research topics for the future:
•• How to predictHow to predict CMEsCMEs/flares before they /flares before they occur?occur?
•• Topology evolution: fromTopology evolution: from CMEsCMEs to to interplanetary clouds?interplanetary clouds?
•• How to predict How to predict geoeffectivenessgeoeffectiveness??
•• Better modelsBetter models//observations of CME observations of CME propagation towards Earthpropagation towards Earth..
•• Separate solarSeparate solar effectseffects onon terrestrial terrestrial weatherweather andand climate from revealclimate from reveal humanhumanimpactsimpacts andand sell thatsell that well towell to the publicthe public!!
Research topics for the future:Research topics for the future:
Space weather experts:remember the fundamental law for
data evaluation in science:
• There are lies…• damned lies…
• and statistics! Let us continue searching for the physicallinks between causes and effects of the
long chain connecting the Sun to the Earth
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ESA Space Weather Workshop:ESA Space Weather Workshop:Developing a European Space Weather Developing a European Space Weather
Service NetworkService NetworkSWENET: Space Weather European SWENET: Space Weather European
NetworkNetwork33--5 November 2003, ESTEC, Noordwijk5 November 2003, ESTEC, Noordwijk
RainerRainer SchwennSchwennMaxMax--PlanckPlanck--Institut fürInstitut für AeronomieAeronomie
Lindau, GermanyLindau, Germany
Improving prediction of space weather disturbances –what is needed?
