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Geospace research with optical measurements within the ICESTAR-IHY-IPY programme. Kauristie, K., Partamies, N., Mäkinen, S., and Kuula, R. ICESTAR and IHY Teams. Outline. IPY, IHY and ICESTAR programmes: Who, How and When? Activies related with optical measurements
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Geospace research with optical measurements within the ICESTAR-IHY-IPY programme Kauristie, K., Partamies, N., Mäkinen, S., and Kuula, R. ICESTAR and IHY Teams
Outline • IPY, IHY and ICESTAR programmes: Who, How and When? • Activies related with optical measurements • Examples of challenges in magnetosphere-ionosphere coupling: • Mapping issues • Estimating energy flux of auroral precipitation • Future propects
ICESTAR-IHY-IPY • ICESTAR (2005-2009) • Project Office in Siena College (US) • Sponsored by SCAR • Interhemispheric Conjugacy Effects in Solar-Terrestrial and Aeronomy Research • International Heliophysical Year (IHY, 2007-2008) • Project Office in NASA/GSFC (USA) • Endorsed e.g. by COSPAR, IUGG, NASA, and UN • In addition to solar-serrestrial also universal processes in the heliosphere • Coordinated Investigation Programmes • International Polar Year (IPY, Mar 2007 – Mar 2009) • March 2007 – March 2009, Project Office in BAS (UK) • Launched by ICSU and WMO • Six science themes (social and natural sciences) • Expressions of Interests and core projects
Heliosphere impact on geospace • IPY core project (#63) conducted by ICESTAR, IHY (International Heliophysical Year) and 27 other consortia with scientists from 22 countries. • Science about coupling phenomena affected by solar activity and cosmic background radiation • Between the different atmospheric layers • Between the magnetosphere and ionosphere • Between the different hemispheres • In addition • Development of Virtual Observatories • New instrumentation and technology • http://www.space.fmi.fi/ipyid63
Auroral Optical Network • Lead Contact: Prof. Ingrid Sandahl and the ALIS Team at IRFU • Objectives: • Information exchange between institutes operating instrumentation for optical auroral observations • Coordinated measurement campaigns • Intercalibration of instruments • Meeting point: Optical meetings • Homepage: http://www.alis.irf.se/auropt/
Optical stations • North: Swedish, Norwegian, Japanese, Italian, Russian, UK, US and Canadian stations • South: Halley, Syowa, ZhongShan, Mario Zucchelli, AGONET P1, P2, P5, and South Pole
Virtual Observatories:gaia-vxo for optical and riometer data • Gaia-vxo V1.0: Browser for summary data already available in http://gaia-vxo.org http://gaia-vxo.org • Built by the University of Calgary, collaboration with University of Lancaster and Finnish Meteorological Institute
Magnetically conjugate instrument networks Fig: A. Weatherwax • Three-letter name codes: Manned stations • P#: U.S. AGO/PENGUIn sites • Crosses: Recently deployed British low-power magnetometers. • M# & diamonds: Proposed U.S. autonomous low-power magnetometers • A1 and A2: proposed multi-instrument ARRO sites
Interhemispheric relationships:SuperDARN Radars • Maps of the Super Dual Auroral Radar Network (SuperDARN) arrays over the Northern (left) and Southern (right) polar regions. The Antarctic map shows fields-of-view for existing (yellow) and planned (orange) radars.
Aeronomy research in ”Heliosphere impact on geospace” • DEEVERT-IPY, Dr. H. Roscoe, British Antarctic Survey, UK • NOBILE, Dr. S. Masi, La Sapienza University, Italy • SWIMPA, Dr. E. Correia, CRAAM, Brazil • TIMIS, Prof. Y. Yampolsky, National Academy of Science, Ukraine • CRSAAMU, Prof. T. Aso, National Institute of Polar Research, Japan • Alaska Project, Dr. Y. Murayama, National Institute of Information and Communications Technology, Japan
Interhemispheric relationships in meso-scale auroras • Global scale auroras are known to be similar, but how about mesoscales (L=100-1000 km)? • ASC images: evolution of individual auroral structures can also have interhemispheric similarities. • The real conjugate point of a station can move hundreds (tens) of km in longitude (latitude) during one hour. Reference: Sato et al., GRL 2005
Estimating global precipitation fluxes with simulations and satellite data • Germany and Lummerzheim: conversion based on preflight calibration • Liou: conversion based on empirical calibration with DMSP data • Other factors: dayglow and slant path removals Reference: Palmroth et al., 2006
Inverting energetics of electron precipitationfrom ASC images • Janhunen (JGR, 2001) • Inversions of volume emission rate and energy fluxes as a single step (ASCinv) • Based on Rees (1963,1989) and Rees and Luckey (1974) formulas for electron range, energy dissipation formula, blue photon yield, and conversion between blue and green and red intensities. • Energy range 0.1-8 keV • Partamies et al. (Ann. Geophys, 2004) • Comparisons with DMSP and EISCAT • EISCAT:Relative errors <50% in 36% of comparisons. • DMSP: Excellent consistency in favourable conditions (stable arc) • Energy fluxes OK, more problems with number fluxes. • Better results with the formulas of Sergienko and Ivanov (1993)
1st data set • ASC images of KIL with the EISCAT TRO beam in the FOV. • EISCAT electron density data and conductivity end energy flux estimates (SPECTRUM by Kirkwood 1988) • 6 periods of substorm activity (~650 points) • Auroral intensities 1-17 kR, homogeneous auroras
Altitude effect of electron precipitation • Energy flux as deduced from 557 nm auroras correlates best with Ne at ~100 km and with Te at ~230 km altitude. Ne and Te from EISCAT data. Ne Te
557 auroras and electron content and in the E-layer • Electron content: correlation 0.69, Linear fit: TEC=0.0663×Eflux+0.24 • =ΣHall/ΣPedersen: poor correlation (0.38), also with I557/I630
EISCAT and ASC data intercalibration • Electron Eflux by ASC inversion and by SPECTRUM • Correlation 0.7. Linear fit: EfluxEISCAT=1.38×EfluxASC+0.7
2nd data set • KIL ASC images, energy fluxes integrated over the camera field-of-view (hereafter fov-power) • 8×8 superpixels • 17 1-2 hour substorm periods (>2000 points) • Comparisons with • IE-index (local AE) • Akasofu epsilon: ε=107vB2sin4(θ/2)l2
Distributions of fov-power values • 1-2 GW value most typical, does not depend on the rate of solar input energy • In the morning sector occasionally also higher, 4-6 GW values
When fov-power correlates with IE-index? T=12 min • When 12 minεdt< 100 TJ fov-power correlates best with IE-index, i.e. most of the activity is at KIL latitudes • In these conditions fov=0.0074×IE+0.56 • Ahn (1983) Global power=0.06×IE, thus fov can be 15-25% of the global precipitation power T=10 min
Summary • Challenge for IPY-IHY-ICESTAR: To understand quantitavely how the different components of geospace respond as a unified system to the solar activity • Multi-instrumental collaboration necessary • Optical networks have a crucial role in this work. If you want to join, please • Tell us about your instrumentation • Submit a CIP and/or check what other people plan to do • Join GAIA!
Next stop: Kick-off meeting • Feb 5-9 2007, Finnish Meteorological Institute, Helsinki • Topics • Get together • Management issues: Steering committee etc. • PR- and Outreach programme • Campaign schedule • Cataloging the instrumentation maintained by the Programme • Data sharing issues
IPY-project Kick-off meeting • Feb 5-9 2007, Finnish Meteorological Institute, Helsinki Web-sites • IPY project 63: http://www.ava.fmi.fi/ipyid63 • IHY home page: http://ihy2007.org • ICESTAR home page: http://www.siena.edu/physics/ICESTAR • Coordinated Investigation Projects: http://www.ihy.rl.ac.uk/CIP_list.shtm
New station to Belgrano? • Location 77.87 S, 34.62 W (500 km west from Halley). • Internet access • Previous ASC recordings 1963-1985 • The Antarctic research center of Argentina is willing to take care of the transportation and local maintenance • Does anyone have a spare camera to lend?
IMF By driven interhemispheric asymmetries • Comparisons of simultaneous Polar VIS and IMAGE FUV images of substorm aurora MLT-locations (left) in southern and northern hemispheres. • IMF By is the main controlling factor, dipole tilt causes a secondary effect • Observations show order of magnitude stronger interhemispheric asymmetries than the empirical magnetic field models T96 and T02 suggest. Reference: Ostgaard et al., GRL, 2005.
Mesosphere and LowerThermosphere Radars • Current Antarctic MLT Sites South Pole, Scott Base, Davis, Syowa & Rothera • Current Arctic MLT Sites Esrange, Andennes, Tromso, Svalbard, Dixon Island, Resolute Bay, Yellowknife, Barrow Some data available online from MLT radar database http://sisko.colorado.edu/TIMED