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The EISCAT Radar Facilities. Ian McCrea STFC RAL. What is EISCAT?. International Scientific Association Established agreeement since 1975 First observations in 1981 HQ in Sweden. EISCAT’s Mission Statement. EISCAT aims to make available the necessary knowledge and techniques:
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The EISCAT Radar Facilities Ian McCrea STFC RAL
What is EISCAT? • International Scientific Association • Established agreeement since 1975 • First observations in 1981 • HQ in Sweden
EISCAT’s Mission Statement EISCAT aims to make available the necessary knowledge and techniques: • To understand the various forms of coupling between the Sun, the terrestrial magnetosphere and the upper atmosphere of the high-latitude regions • To understand the plasma physics and dynamics responsible for these interactions • To investigate the effects of natural and anthropogenic forcing on the upper atmosphere • To facilitate the better monitoring and prediction of these processes
Incoherent Scatter • Electrons re-radiate the radar signal with random phase • Electron motion follows the thermal fluctuations in the ion gas. • If the probing wavelength is longer than the Debye length, the fluctuations dominate the scatter. • Radar pick outs towards and away propogating ion-acoustic waves satisfying the Bragg condition
EISCAT Facilities: Mainland UHF • Three identical fully steerable dishes, frequencies ~ 928 MHz. • Transmit at T, receive at T, K, S • Additional reception at 1.42 GHz • Increasing problems with mobile phones at remotes • Tromsø guaranteed to end of 2013
EISCAT Facilities: Mainland VHF • Frequency ~224 MHz. • Cylindrical paraboloid antenna 120m x 40m • Dish in four independent sections • Steerable in meridian plane • Limited beam-steering in zonal direction • Two very large klystrons, only one working
EISCAT Facilities: ESR • Frequency ~500 MHz. • Two dishes: one steerable, one fixed field-aligned • Share common transmitter • Small “TV Tx” style klystrons • Third (Chinese) ESR dish by 2014?
EISCAT Facilities: Heater & Dynasondes • Heater Frequency 4-8 MHz • Two Tx arrays • ERP up to 1.2 GW • Advanced ionosondes at Tromsø and ESR
Original Science Motivation:“The Seven Wonders of EISCAT” Seven initial objectives of EISCAT (as defined by EISCAT Scientific Advisory Committee, 1979) • Detailed mapping of auroral arcs • High-resolution D and E-region response to precipitation • Understanding of association between auroralelectrojets and gravity waves • Clear detection of the polar wind
Original Science Motivation:“The Seven Wonders of EISCAT” Seven initial objectives of EISCAT (as defined by EISCAT Scientific Advisory Committee, 1979) • Measurement of polar cap convection patterns • Ionospheric images of polar cleft, plasmapause and plasma sheet • Detailed measurements of the polar mesosphere
Future Systems: MAISR • Proposal of NSF Office of Polar Programs • Study differences between Northern and Southern hemispheres • Different magnetic field, different topography, different vortex • Could be ready for deployment in 2015 • US will fund 80% of facility – looking for international partners for the other 20%
ESFRI Projects for Env. Sciences IAGOS-ERI EURO-ARGO SIOS Status 2009 EUFAR-COPAL AURORA BOREALIS LIFEWATCH EISCAT-3D EPOS EMSO ICOS