2. ICESTAR Linking near-Earth Space to Polar Regions Volodya Papitashvili Space Physics Research Laboratory University of Michigan, U.S.A. A Workshop for Planning the SCAR Scientific Programme Interhemispheric Conjugacy Effects in Solar-Terrestrial and Aeronomy Research April 22-23, 2004, Villefranche sur Mer, France

3. Conjugate Aurora Borealis and Aurora Australis Year= 2001 Day = 305 Hour = 11 Min = 53 Sec = 28 Alt.= 200 km Geographic Dipole CGM Lat. Long. Lat. Long. Lat. Long. IGRF+T96 North 61.0 189.0 57.8 243.7 57.4 248.0 Apex XGSM = -4.0 YGSM = -0.1 ZGSM = -0.7 R = 4.0 B-min = 343 nT Conjugate -48.9 162.8 -54.1 245.8 -57.8 248.6 IGRF+T96 South -53.0 166.3 -57.5 251.6 -61.3 255.8 Apex XGSM = -11.4 YGSM = -1.0 ZGSM = -1.7 R = 11.5 B-min = 11 nT Conjugate 64.6 192.4 61.7 244.1 61.6 248.8  October 22, 2001: POLAR’s Visible Imaging System recorded simultaneous brightening of aurora borealis in the Northern polar cap and aurora australis in the Southern polar cap  These images confirm a three-century old theory that auroras in the Northern and Southern hemispheres are nearly-mirror images of each other Mapping of conjugate auroras to the magnetospheric equatorial plane IGRF and External Fields Calculator: http://nssdc.gsfc.nasa.gov/space/cgm/t96.html Why are the mappings are so different? It seems that FACs might not be properly balanced between two hemispheres in T96 model Courtesy of John Sigwarth, Univ. of Iowa

4. ICESTAR - Linking near-Earth Space to Polar Regions Villefranche, France, April 22, 2004 SCAR Scientific Research Programme ICESTAR: Interhemispheric Conjugacy Effects in Solar-Terrestrial and Aeronomy Research Science and Implementation Plan Submitted by the Standing Scientific Group on Physical Sciences Expected duration: 2005 – 2009 Expected SCAR funding: US $95,000 At this Workshop we outline scientific backgrounds, goals and objectives, and potential implementation plans for establishing under the auspices of SCAR a five-year international scientific research programme for coordinated bi-polar research in the fields of solar-terrestrial physics and polar aeronomy

5. Challenge: Understand geospace environment and its dynamical response to external forcing from solar activity. Objectives: To create a distributed Virtual Arctic and Antarctic Geospace Observatories Network, and To identify and quantify various mechanisms that control bi-polar regional differences and commonalities in electrodynamics of the Earth’s magnetosphere- ionosphere system and aeronomy of the upper atmosphere over the Arctic and Antarctic. Interhemispheric Conjugacy Effects in Solar-Terrestrial and Aeronomy Research

6. The ICESTAR programme will deal with various geophysical and upper atmospheric phenomena developing either simultaneously over both the Northern and Southern polar regions (i.e., controlled by external forces and producing bi-polar effects) or connected through the interhemispheric geomagnetically-conjugate coupling. The uniqueness of this new programme is that it will focus for the first time on identification and specification (quantification) of various mechanisms that control bi-polar regional differences or commonalities in the magnetosphere-ionosphere coupling and the corresponding upper atmospheric phenomena over both polar regions. These bi-polar (or interhemispherically conjugate features) might be intrinsic to the polar ionosphere and upper atmosphere or be caused by long-term or abrupt changes in the near-Earth electromagnetic environment forced by the solar activity. The programme outcome will be the better understanding of concerted responses of both polar regions to electromagnetic variations and plasma dynamics in interplanetary space that specify near-Earth space climate and weather. It is suggested that SCAR should lead this new programme in collaboration with the International Arctic Science Committee. Interhemispheric Conjugacy Effects in Solar-Terrestrial and Aeronomy Research

7. IGRF-Based Magnetic Conjugacy Greenland West Coast and Eastern Antarctic NAQ THL P5 P3 P4 VOS Greenland West Coast Magnetometer Chain ~40  CGM meridian (12 stations) Eastern Antarctic ~40  CGM meridian (5 stations) 65  75  85   60  7070 8080          BAS LPMs A81   P2 SPA P6 P1

8. Realistic Magnetic Conjugacy of High-Latitude Antarctic and Greenland/Canadian Stations SouthCGM Lat. Lon. MLT Noo n MLT Conjugacy IGRF+T89c MLT Noon CGM Lat. Lon. North P5  86.6 30.714:47All time14:5285.533.8 THL VOS  83.3 54.613:03at open14:5283.836.2SVS SUD  80.9 105. 6 09:35magnetic09:1380.9106.6NRD P4  80.4 46.613:38field14:1579.642.2UPN P1  80.0 17.515:42lines15:5179.318.7CLY SPA  73.9 18.915:34Q 21–24 UT D open16:0773.214.7 IQA P3  71.6 40.414:02Q 22–24 UT D 22–2314:3372.137.1SKT A81  68.5 36.214:1800 – 24 UT14:2568.239.6FHB IGRF + T89c  Magnetically conjugate mapping of Greenlandic station Frederikshab (FHB) into the “field-of-view” of Antarctic near-conjugate British AGO station A81 during a 24-hrs UT day (Equinox, Kp = 0)  Note that the projection point wanders over the station’s FOV edge to few hundred kilometers Geographic Latitude Geographic Longitude 155 km 310 km Nord vs Sude H E Z

9. Key questions: 1.How the states of Earth’s magnetosphere differ qualitatively as well as quantitatively under extreme, moderate, and quiet solar wind conditions? 2.Does the auroral activity during substorms arise from instabilities in the ionosphere or does this aurora simply mirror plasma motions in the outer magnetosphere? How much do the dark and sunlit ionospheres control the polar substorm dynamics? 3.To what extent are the ionized and neutral high- latitude upper atmospheric regions affected by mechanical and electrodynamic inputs from the lower atmosphere? Interhemispheric Conjugacy Effects in Solar-Terrestrial and Aeronomy Research

10.  Reconstruction of high-latitude ionospheric electrodynamics for quiet and disturbed conditions in near-Earth space. Aimed at using the best available models of ionospheric electrodynamics to quantitatively specify the state of magnetosphere - ionosphere coupling over both the Northern and Southern polar regions at any given time.  Determine the bi-polar connection between the ionosphere and magnetosphere. Aimed at identifying mechanisms of interhemispheric conjugacy for various high-latitude geophysical phenomena by studying primary drivers of the active aurora during magnetic storms/substorms. Interhemispheric Conjugacy Effects in Solar-Terrestrial and Aeronomy Research Rationale:  Bi-polar regional differences and commonalities over the Arctic and Antarctic. Aimed at quantification mechanisms that control interhemispheric conjugacy of various high-latitude phenomena via geomagnetic field lines and through the common sources in the interplanetary conditions.  Interhemispheric coupling from the ‘top-to-bottom’ and vice versa. Aimed at understanding the interaction between the high- latitude ionosphere and neutral upper/middle/lower atmosphere over both polar regions.

11. Interhemispheric Conjugacy Effects in Solar-Terrestrial and Aeronomy Research

12.  To identify and promote deployment (with efforts to coordinate logistics and technology transfer) of various observational arrays over both the Arctic and Antarctic that deal with the solar-terrestrial physics phenomena, specifically with their interhemispheric aspects.  To develop and make available to the worldwide scientific community a distributed Arctic and Antarctic solar-terrestrial physics and aeronomy data source network (Virtual Arctic & Antarctic Observatories, VAAO, deployed in cyberspace) that would allow easy data retrieval from various locations spread over the World Wide Web.  To coordinate joint studies of various interhemispheric and bi-polar STP phenomena between the SCAR member countries, providing an international forum for reporting the progress and helping collaboration. Interhemispheric Conjugacy Effects in Solar-Terrestrial and Aeronomy Research Goals:

13. TAG-A: High-latitude auroral and ionospheric electrodynamics for quiet, moderate, and disturbed conditions in near-Earth space, and its regional differences and commonalities over the Arctic and Antarctic. TAG-B: Geomagnetic (interhemispheric) conjugacy between the magnetosphere and both the Northern and Southern polar ionospheres during geomagnetic storms and substorms. TAG-C: Coupling between the polar ionosphere and neutral atmosphere from the ‘bottom-to-top’ and the global electric circuit. TAG-D: VAAIGO.NET: Virtual Arctic and Antarctic Geospace Observatories Network – a World Wide Web portal for the ICESTAR programme and SCAR’s SSG/PS. Interhemispheric Conjugacy Effects in Solar-Terrestrial and Aeronomy Research Task Action Groups: