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MULTIPLEX
Ian McCrea, Tim Yeoman, Mike Kosch, Farideh Honary
Mike Rietveld, Anita Aikio, Ove Havnes, Ingrid Sandahl
Polar Atmosphere Working Group: Membership
• PPARC funded– Dr. Ian McCrea (RAL, chair)
– Prof. Farideh Honary (Lancaster)
– Dr. Tim Yeoman (Leicester)
• NERC funded– Prof. John Plane (UEA)
– Dr. Howard Roscoe (BAS)
• Joint funded– Prof. Nick Mitchell (Bath)
Polar Atmosphere Working Group: Context
• PPARC “Solar system science strategy” (2002)– Three key themes
• Energy flow in the solar system
• Fundamental plasma processes
• Conditions for life
• NERC “Science for a sustainable future” (2002)– Importance of global change
– Solar effect on climate identified as a priority
• Town Meeting – Coseners House 30/09/2003– Synergy between PPARC and NERC programmes
– Cross-council working group to map out strategy
Polar Atmosphere Working Group: Programmes
• MULTIPLEX (PPARC)– Fundamental physics of energy flow
– Importance of non-linear coupling
– New emphasis on active techniques
– Based on facilities already in operating plan
– Cost £8m over five years, but only £1m is new money
• DEEVERT (PPARC/NERC)– Effects of solar variability on climate
– Importance of non-linear coupling and wave processes
– Combines PPARC and NERC observation and modelling
– Uses many of same facilities as MULTIPLEX
– Cost £10m over five years, half from NERC
– £0.5m new money from PPARC, leverages £5m from NERC
Solar-terrestrial energy flow
• The problem:– Good macroscopic description of energy transfer processes exists…..
…but lacks predictive power
– Energy flow depends critically on non-linear coupling
– Need to know which mechanisms are important and when
– Need to understand how system evolves from one state to another
Solar-Terrestrial Energy Flow
Composition, circulation
heat balance
Solar energy input
Conductivity
Electro-magnetic radiation
Acceleration mechanisms
SW energetic particles
Ionisation and particle heating
Solarwind
Magnetic reconnection
Electron and proton aurora
InducedE-fields
Ion drift
Storage and release
Neutral wind
Plasma irregularities
and turbulence
Anomalous heating
Joule dissipation
Ionospheric electrodynamics
Chemistry and transport
Anomalous resistivity
Solar-terrestrial energy flow
• The problem:– Good macroscopic description of energy transfer processes exists…..
…but lacks predictive power
– Energy flow depends critically on non-linear coupling
– Need to know which mechanisms are important and when
– Need to understand how system evolves from one state to another
• Strategy for solution:– Active experiments allow us to stimulate non-linear processes
– New, improved diagnostics
– Synthesis of experimentation and modelling
The MULTIPLEX programme
• Why now ?– Paradigm shift from phenomenology to directed experimentation
– New active experimental techniques
– Major new UK facilities (e.g. SPEAR)
– Novel data raising new insights and questions
• Why UK ?– UK is world-leading in active experimentation
– UK has access to world-class instruments
– UK has state-of-the-art numerical models
– UK has excellent track record of exploiting international programmes
EISCAT Tromsø HF Heater
Artificial Aurora
Rings form initially, collapsing into blobs
Rayed structures form along magnetic field
Non-thermal signatures show that collapse of rings corresponds to features descending in altitude
15:09 15:17 15:25 15:33 15:41 15:49 15:57 16:05 16:13 16:21 16:29 16:37 16:45 16:53
1000200030004000500060007000
Tem
pera
ture
(K)
UT
15 12 9 6 3 6 9 12 15 12 9 6 3 6 9 12 15 12 9 6 3 6 9 12 15 12 9
0
2
4x 10
11
Den
sity
cha
nge
(Ne/
m3
)
15:09 15:17 15:25 15:33 15:41 15:49 15:57 16:05 16:13 16:21 16:29 16:37 16:45 16:53
200
220
240
Altit
ude
(km
)
15 12 9 6 3 6 9 12 15 12 9 6 3 6 9 12 15 12 9 6 3 6 9 12 15 12 9
15:09 15:17 15:25 15:33 15:41 15:49 15:57 16:05 16:13 16:21 16:29 16:37 16:45 16:53
200
220
240
Altit
ude
(km
)
15 12 9 6 3 6 9 12 15 12 9 6 3 6 9 12 15 12 9 6 3 6 9 12 15 12 9
Raw
bac
ksca
tter p
ower
(log
10)
0
1
2
EISCAT shows that strong electron temperature enhancements occur…..
….but these cannot explain the observed emission
CUTLASS observations of plasma waves show which coupling processes are involved.
Dynamics of auroral arcs
Dynamics of auroral arcs
Anomalous echoes from natural aurora
coherent scatter from ion acoustic waves
structure size under 300 m at 500 km altitude
varies on 0.2 second time scale
The EISCAT Svalbard Radar
• Probing wave and particle populations on open field lines
SPEAR, CUTLASS and the ESR
Off On Off
Off On Off
Pla
sma lin
e
am
plit
ude
Ion lin
e a
mplit
ude
The MULTIPLEX programme: Goals
• Understand energy exchange between magnetosphere, ionosphere and thermosphere– Move from qualitative to quantitative understanding
• Quantify role of non-linear coupling in – Auroral acceleration and structure – Field-aligned currents and waves– Ionospheric irregularities– Non-thermal plasmas– Ion-neutral coupling
• Linkages between processes at different scale sizes• Understanding key mechanisms
– Proton aurora– Artificial aurora– Coherent echoes
The MULTIPLEX programme: Questions
• What processes mediate energy flow ?– How important is non-linearity ?
– Which non-linear processes are most important ?
– How are they triggered ?
• How can we explain observed phenomena ?– Auroral acceleration and structure
– Field-aligned currents and waves
– Ionospheric irregularities
– Non-thermal plasmas
– Ion-neutral coupling
• Same questions important for whole plasma universe.
The MULTIPLEX programme: Facilities
• EISCAT– Definitive measurements of plasma parameters– Active experiment capabilities
• SPEAR– Unique new UK facility for active plasma experiments
• CUTLASS– Measurements of global electrodynamics– Essential support for SPEAR and EISCAT experiments
• SIF/Tromso Imager– Studies of auroral energisation and structure
• FPI/SCANDI– Understanding scale sizes in thermosphere dynamics
• Magnetometers– Relating ULF waves and field-aligned currents
• Riometers– Wide-scale measurements of energetic particles
Polar Mesosphere Summer Echoes (PMSE)
Seen in EISCAT radar in last 15 years Charged dust/ice? Breaking of upgoing gravity waves? Early phase in the formation of noctilucent clouds?
PMSE
Overshoot effect – Lower dust density, or larger dust grains ??
PMSE modulation using the EISCAT Heater
EISCAT
The importance of EISCATThe importance of EISCAT
• EISCAT Svalbard RadarEISCAT Svalbard Radar– Essential for understanding SPEAR scienceEssential for understanding SPEAR science– Unique new auroral interferometry capabilityUnique new auroral interferometry capability– Invaluable context for optical dataInvaluable context for optical data
• EISCAT UHF RadarsEISCAT UHF Radars– Tristatic capability unique for electrodynamicsTristatic capability unique for electrodynamics– Essential for ionosphere-thermosphere couplingEssential for ionosphere-thermosphere coupling– Unique IPS capability for solar wind studiesUnique IPS capability for solar wind studies
• EISCAT VHF RadarEISCAT VHF Radar– Optimised for low-density plasma (mesosphere and topside)Optimised for low-density plasma (mesosphere and topside)– Essential for full height profiles of dynamicsEssential for full height profiles of dynamics
• Tromso HF HeaterTromso HF Heater– World’s leading facility for active experiments in plasma physicsWorld’s leading facility for active experiments in plasma physics– Unique active experiments on mesopause phenomenaUnique active experiments on mesopause phenomena
Extended runs of high latitude Extended runs of high latitude data…data…
5-23 February 2001
Present IS Radar StatusPresent IS Radar Status10 radars operate routinely10 radars operate routinely
AMISRAMISR
384 Panels, 12,288 AEUs3 DAQ Systems
3 Scaffold Support Structures
AdvancedModularIncoherentScatterRadar
Phased array IS radarPhased array IS radar
AEU
32 AEUs = 1 panel
128 panels = 1 face (4096 AEUs) at ~2MW Possible Andøya deployment
2 panels on far-field test rig
International Polar YearInternational Polar Year
• 2007 is the next International Polar Year 2007 is the next International Polar Year (and the 50th, 75th, and 125th (and the 50th, 75th, and 125th anniversaries of the International anniversaries of the International Geophysical Year and the first two Geophysical Year and the first two International Polar Years). International Polar Years).
• Will run (at least) the high-latitude Will run (at least) the high-latitude incoherent scatter radars for the entire incoherent scatter radars for the entire year as part of the ICESTAR/IHY ‘cluster’.year as part of the ICESTAR/IHY ‘cluster’.
Aims of MULTIPLEX
• Quantify temporal and spatial variability of energy deposition• Study large and small-scale energy transfer processes• Focus on energy coupling and non-linearity• Exploit both natural and artificially-generated processes• Assimilate data into models for predictive studies• Synergy with other studies (CAWSES, LTCS, DEEVERT, ISPAM)• Establish a legacy of instruments available after IPY