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The EISCAT_3D Science Case: Current Status (Part 1). Ian McCrea (RAL), Anita Aikio (Oulu) and the EISCAT_3D Science Working Group. What is EISCAT?. International Scientific Association Established agreement since 1975 First observations in 1981 HQ in K iruna , Sweden.
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The EISCAT_3D Science Case:Current Status (Part 1) Ian McCrea (RAL), Anita Aikio (Oulu) and the EISCAT_3D Science Working Group
What is EISCAT? • International Scientific Association • Established agreement since 1975 • First observations in 1981 • HQ in Kiruna, 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 propagating 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
Future Systems: EISCAT_3D • Successor to EISCAT mainland systems • Located in northern Scandinavia • Possible construction from 2015 • On ESFRI roadmap since 2008 (environment category) • Multi-static system using phased arrays • Combines: • Wide-scale fast beam scanning • Small-scale sub-beamwidth imaging • High power and sensitivity • Continuous low-power operations • Flexbility for transmission and reception • Re-use of low-frequency astronomy techniques
Preparatory Phase WP3: Science Case Work Package • Engaging with potential new users • Holding targeted workshops • Gathering requirements for new science • Revising/developing the science case • Feeding science demands back to radar design • Issuing periodic versions of science case, consistent with the PSD
The Science Working Group • Convenors: Anita Aikio, Ian McCrea • 5-10 members at any time • Mix of existing and new EISCAT users • Membership rotates annually • Cover a wide range of science topics • Atmospheric science, space weather & modelling • Two meetings with each committee, email exchanges in between
Science Case: Version 1.0 • Published June 30th 2011 • Executive Summary • Introduction to EISCAT_3D • The Science Case: • Atmospheric physics and global change • Space and plasma physics • Solar system science • Space weather and service applications • Radar techniques, coding and analysis
Key Capabilities • The most sophisticated research radar ever! • Five key capabilities: • Volumetric imaging and tracking • Aperture Synthesis imaging • Multistatic, multi-beam configuration • Greatly improved sensitivity • Transmitter flexibility • These abilities never before combined in a single radar
Volumetric Imaging • Image a broad three-dimensional field-of-view • Quasi-simultaneous horizontal structure (as well as vertical) • Rapid scanning or post beam-forming
Aperture Synthesis Imaging • Imaging concept already developed by UiT on the ESR system • Extended to a modular array for EISCAT_3D type array and demonstrated at Jicamarca
Improved Flexibility and Sensitivity • Large, fully digital aperture • Very flexible transmitter • State-of-the-art digital processing
Flexible Experiments • Continuous, unattended operations • Multiple, interleaved experiments • Intelligent scheduling • www.eiscat3d.se/drupal/content/vision-eiscat3d
Interleaving and Adaptation • Multiple simultaneous modes • Different applications • ISR (specific v general purpose) • Satellites/space debris • Astronomy/Solar system • What happens to scheduling? • “Intelligent scheduling” • Trigger points? • Tom Grydeland’s vision…
Radar techniques, coding and analysis:Topics covered • New coding techniques: Polyphase codes, amplitude modulation, aperiodic codes • Antenna coding techniques Automated strategies to identify and track objects and events • Intelligent techniques to control scheduling and interleaving of experiments
New analysis methods Analysed tau8 from standard GUISDAP (left) and directly from raw samples (right). One minute resolution.
Radar techniques, coding and analysis:Planned Activities • MarkkuLehtinen’s “Handbook” has developed full theory of measurement principles for phased arrays • Implementation of general purpose experiments at Tromsø • Use of LOFAR as an open technology platform • Development of data handling techniques for very large data sets • Contribute to e-infrastructure development for the space weather community
Space Weather and Service Applications:Topics Covered • Identification and study of ionospheric structures capable of affecting communications and position-finding • Use of EISCAT_3D data for nowcasting, validation and constraint of ionospheric models • Combination of data and modelling for ionospheric forecasting and as a tool to respond to space weather alerts • Ground-based support for geospace science missions (e.g. SWARM)
Space Weather and Service Applications:Key Issues • Regular space debris observations • (e.g. for ESA SSA) • Validation of space debris models • Potential for improvements in forecast/acquisition capabilities • Long-period continuous observations provide basis data for all kinds of models • Real-time predictions and status reports in response to community needs
Engagement with SW Operations • Getting from radar data to operational space weather products and services • - Targeted radar operations for SW studies • - Observations in response to SW events • - Direct data assimilation into models, value added data • This needs direct engagement with the operational user community
INFRA-2012-1.1.27. Research Infrastructures for space weather A project under this topic should aim at integrating the key research infrastructures in Europe for the observation and study of the ionosphere and magnetosphere. Infrastructures of relevance include the European Incoherent Scatter radar system (EISCAT) and other incoherent scatter radar systems, satellites, solar ground based-observatories, ionospheric sounders, Global Navigation Satellite Systems (GNSS) receivers and ground magnetometers. The project will facilitate access to these research infrastructures and to standardized and validated observational data in particular real-time data. The research supported in this field should result in models and databases that also could be a basis for operational forecasts and warnings to society. 30M EURO for call heading (competitive between 27 proposals)
INFRA-2012-3.1: International cooperation with the USA on common data policies and standards relevant to global research infrastructures in the environment field The project to be supported under this topic should aim at the development of common data policies and standards in the field of environmental research, in particular related (but not exclusively) to space weather facilities (two examples of such facilities are EISCAT (EU) and AMISR (USA)), atmospheric observatories (ICOS (EU), NEON (USA)), ocean observatories (EMSO (EU), OOI (USA)) or tectonics-related observatories (EPOS (EU), Earthscope (USA)). The project should assist in the creation of a long-term sustainable framework (i.e. full life cycle of data) for the coordination of actions at global level, as well as address interoperability (including compliance with GEOSS principles), harmonisation of data formats, data validation and curation. The project should clearly describe its complementarity and collaboration with the correspondent USA project(s) that is or may be funded by NSF. The outcomes should be readily extendable to other international communities wishing to join the initiative. When appropriate, the work should build on and extend the activities of existing European projects in the field. 2M Euro call.