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EISCAT Scientific Association The EISCAT_3D Science Case Anders Tjulin1 ([email protected]), Ingrid Mann1,2, Ian McCrea3, Anita Aikio4 and Thomas Ulich5 1EISCAT Scientific Association, Sweden; 2Umeå University, Sweden; 3STFC Rutherford Appleton Laboratory, United Kingdom; 4University of Oulu, Finland; 5Sodankylä Geophysical Observatory, Finland EISCAT_3D EISCAT, with international partners, is preparing to construct the next generation radar: EISCAT_3D. It will consist of multiple phased arrays and use state-of-the-art signal processing and beam-forming techniques to become the world's most sophisticated research radar. The five key capabilities of EISCAT_3D are: ● e Resolution of space-time ambiguity. s a c ● - 3D volumetric capability. e c n ● e EISCAT Scientific Association Sub-beam width measurements. i c EISCAT is an international research organisation, conducting s ● / Continuous monitoring of solar variability on terrestrial 7 fundamental research into solar-terrestrial physics and p atmosphere and climate. f / atmospheric science. t c ● e Model validation for space weather and global change. j EISCAT was founded in 1976 and the first EISCAT data were o r obtained in 1981. This is a unique set of capabilities of one single facility. p / e s EISCAT operates three incoherent scatter radar systems (224 MHz, . d 3 500 MHz, 931 MHz) in northern Fenno-Scandinavia and on t a c Svalbard. s i e . The EISCAT systems are located in Tromsø (Norway), Kiruna w (Sweden), Sodankylä (Finland) and Longyearbyen (Svalbard). w w EISCAT also operates an ionospheric heater and supporting Suggested EISCAT_3D site set-up instruments such as dynasondes. The planned time-line for the EISCAT_3D system is: EISCAT is at the present funded by seven The EISCAT_3D Science Case member organisations from six countries: 2005 – 2009 FP6 Design Study (completed) The EISCAT_3D Science Case is prepared as part of the ● 2010 – 2014 FP7 Preparatory Phase (ongoing) Suomen Akatemia, Finland Preparatory Phase. It is regularly updated with new releases, EISCAT antennas ● 2014 – 2021 Implementation Phase Tromsø Solar Terrestrial Environment and it aims at being a common document for the whole future Laboratory, Nagoya, Japan 2014 – 2016 Preparation EISCAT_3D user community. ● National Institute of 2016 – 2019 Construction (in stages) The material presented here comes from two science working Polar Research, Japan groups during the two first project years. In addition to the 2019 – 2021 Commissioning (in stages) science working groups, contributions have been obtained ● China Research Institute of from other members of the scientific community, both present Radiowave Propagation, China The EISCAT_3D Preparatory Phase started 1 October 2010. The EISCAT users and potential EISCAT_3D users. ● Norges Forskningsråd, aim is to ensure that the EISCAT_3D project is sufficiently mature The Science Case aims at being a common document of the Norway with respect to technical issues, legal matters and finances. whole future EISCAT_3D user community. Therefore, we ● National Environment EISCAT_3D Preparatory Phase is Funded by the European welcome input and suggestions for improvements of the Research Council, UK Commission under the call FP7-INFRASTRUCTURES-2010-1 document. ● Vetenskapsrådet, Sweden “Construction of new infrastructures: providing catalytic and The Science Case is divided into five main areas, as presented EISCAT receives additional funding from leveraging support for the construction of new research here. Russia, France, Ukraine and the EU. infrastructures”. Atmospheric Physics Space and Plasma Solar System Space Weather and Radar Techniques, and Global Change Physics Research Service Applications Coding and Analysis Research questions: Research questions: Research questions: Key goals for EISCAT_3D: Key goals for EISCAT_3D: Where do upgoing atmospheric gravity How much energy originating from What is the meteoroid mass flux into Identification and study of the Development of optimised observing waves break into turbulence and how do the Sun and near-Earth space is the Earth's atmosphere and what is its ionospheric irregularity structures strategies for large-scale and small-scale they affect the temperature and global deposited in the thermosphere during temporal variation? capable of affecting communications imaging of upper atmosphere processes, circulation? under a range of different geophysical substorms and what effect does it have What kind of orbits do meteoroids and position‐finding techniques. on the various atmospheric regions? conditions. Do solar energetic particle events have and what do they tell us about Use of EISCAT_3D data for now-casting deplete ozone in the stratosphere? Which are the most important meteoroid dynamics and cometary of ionospheric conditions, validation Development of beam- and phase front- What processes link the the variations generation mechanisms of ion dynamics? and constraint of ionospheric models, shaping techniques to optimise the radar for use in different regions of the in surface temperature to geomagnetic outflows and what kind of effect do What is the mechanism behind the combined use of data and modelling atmosphere. activity of solar origin, as suggested in those have on substorm onset? meteor head echoes? for ionospheric forecasting and as a some recent studies? tool to initiate and respond to space Development of automated strategies to What is the plasma physics behind What is the role of meteoric dust in weather alerts. identify and track different types of Are mesospheric thin layers and auroral arcs, small-scale structures, the chemistry and heat balance of the events/objects. noctilucent clouds signs of global naturally enhanced ion acoustic waves middle atmosphere? Development of inter‐operable data change, connected to human activity? and artificial aurora induced by products and their demonstration in Development of intelligent techniques to What kind of sub-surface geochemical ionospheric heater facilities? multi‐instrument comparison and control the scheduling and interleaving How do stratospheric warming events properties do planets and asteroids model assimilation. of EISCAT_3D experiments. affect the dynamics of the mesosphere How is plasma convection structured have and what can they tell us about and thermosphere? on different scales and what the formation of our planetary Providing ionospheric observations to Demonstration of new coding implications does this have for large‐ be used together with satellite Is greenhouse warming of the lower system? techniques, including “perfect codes” scale global models which average measurements to study the physical and amplitude modulation codes, to atmosphere resulting in long-term How is the solar wind accelerated and over hundreds of km? processes in the ionosphere‐ maximise the temporal and spatial cooling of the middle and upper what is the distribution of solar wind Under which situations do the atmosphere system caused by space resolution of the new radar. atmosphere? velocities as a function of solar weather phenomena. inductive electric fields, that are latitude and distance during different Testing of antenna coding techniques, created due to the temporalEISCAT variations Scientific Association solar conditions? Monitoring of the space debris e.g. for the purpose of investigation of ionospheric currents, become environment for the verification of ionospheric vorticity structures via the significant and how do theyMeteor affect thestudies current space debris models. use of orbital angular momentum. magnetosphere and the ground? Identification of new space debris The Ph.D. t hesis ”Radio meteors objects and quantification of space above the Arctic Circle - radiants, Electronorbits and estimated magnitudes” weather induced changes in the orbits by Szasz (2008) describes of known objects. Noctilucent clouds.Photo: Peter Dalin precipitationmeteoroid orbit calculations from EISCAT UHF measurement s. This H+ upflow O+figure upflow displays the sun (yellow), the Earth (blue) and 39 prograde (green) and retrograde (red) met eoroid orbit s. Schematic representation showing the volumetric imaging of an ionospheric layer by EISCAT_3D. With EISCAT 3D we could map the whole dust cloud of the solar system! More information Both hydrogen ion (H+) and oxygen ion (O+) upflows Comparison between measurements of the space Meteoroid orbits calculated from tristatic EISCAT UHF Variations in ozone density (top) and nitric oxide in the topside polar ionosphere were recently debris environment as observed by the EISCAT UHF About EISCAT: www.eiscat.se measurements. Sun (yellow), Earth (blue) and density (bottom) at 46 km altitude, as observed by the observed with the EISCAT Svalbard radar (ESR) in radar (left) and the predictions of the ESA PROOF prograde (green) and retrograde (red) meteoroid About EISCAT_3D: www.eiscat3d.se GOMOS instrument on ENVISAT, following the intense the vicinity of the cusp (Ogawa et al., 2009). model (right) (Markkanen et al, 2009). The clouds of solar particle events (SPEs) during the Halloween orbits (Szasz, 2008). vertically-distributed points correspond to debris superstorm of 2003 (Seppälä et al., 2004). fragments from the Cosmos-Iridium collision. Figure 2. Measurement of space debris by the EISCAT UHF system on 14-15 May 2009 (left) and PROOF simulation (right)..
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