2000 Incoherent Scatter Coordinated Observation Days
URSI-ISWG

In the following table, column 2 gives the start and end date of the experiment, column 3 gives the day of the week of the start of the experiment, column 4 is the length of the experiment and column 5 shows the date of the new moon.

Incoherent Scatter Coordinated Observation Days should start at 1300UT on the first day indicated (to ensure that all radars are operating correctly by 1600UT) and end at 1600UT on the last day indicated. However, radars are encouraged to start as early as possible on the first day where operational considerations allow.

Notes

1. POLITE
   POLITE aims to advance our understanding of topside light ion morphology and dynamics through a combination of modeling efforts and coordinated observations by the ISR chain and by DMSP satellite overflights. The use of the full latitudinal and longitudinal extent of the ISR chain is critical to the campaign, as one key objective is the study of the latitudinal and longitudinal variations of hydrogen, oxygen, and helium ions. Simultaneous measurements of neutral oxygen, hydrogen, and helium are also important, in order to explore the coupling between ionic and neutral species in the lower topside. The helium ion layer descends in altitude and increases in strength during the wintertime, making observation easier for the ISR chain. Significant asymmetries in field-aligned flows are also at their maximums during summer and winter solstices. IMF support is not very important, but new moon periods are critical since optical support is required for simultaneous neutral species measurements.
   Contact: Phil Erickson
2. Global ionospheric convection - time-dependent model fitting
   It is important that all radars concentrate on ionospheric electric field measurements, preferably in the magnetic field aligned position where possible. The IZMIRAN Electrodynamic Model (IZMEM) has been developed from magnetometer data to reproduce the global electric potential patterns for all seasons. The model is time dependent on the magnitude and sign of the interplanetary magnetic field (IMF) components. Qualtitative tests of the model using data from the STARE and SABRE coherent radar systems, as well as SUPERDARN, have been very encouraging. For quantitative comparisons, which will allow fine adjustment of the model, it is necessary to get an accurate measurement of the ionospheric electric field at several points on the globe simultaneously. Initial quantitative comparisons with EISCAT are good but lack global coverage. For this purpose, a world day campaign of all available incoherent-backscatter radars would be ideal.
   A long run of several days (at least 3-5) is best to cover as many IMF conditions as possible. An existing world day run is scheduled for the summer of 1999. As there is a need to cover all seasons, the next choice would be equinox for 2000. The exact date is not important, although the predicted position of satellites used for IMF measurements could be taken into consideration in-so-far as this is practical.
   Contact: Kosch and Levitin
3. Hi-TRAC: High Time Resolution Auroral Radar Convection. Combines incoherent and coherent scatter radars to provide optimum high latitude convection measurements. High latitude radars should endevour to record high-time resolution line-of-sight velocities over as wide a latitude interval as possible. Low latitude radars should use database (q.v.) modes.
   Contact: John Holt
4. Database: The emphasis should be on broad latitudinal coverage of the F region.
   Contact: Tony van Eyken
5. Wide-Latitude Substorm Dynamics
   These are 'floating' days, the exact operation dates to be selected about one month before based on available predictions. Radars which cannot accommodate this flexibility should run on the default dates. Modes with temporal resolutions better than 5 minutes should be used. In 1999, we should address substorm phenomena with better time resolution.
   Contact: John Foster
6. SPARC
   SPARC brings together researchers in upper atmospheric and space physics from around the world, providing them a set of online collaboration tools and workspaces that link together scientific instruments, data, and models. The collaboratory is itself a subject of study by computer and behavioral scientists who are developing and refining the tools and organizational structures that will make such real-time, online collaborative research commonplace.
   Contact: Tim Killeen
7. Mid-July Baseline
   The purpose of this experiment is to help improve our statistics of all the parameters measured by the ISRs. These are deficient in summer. In particular seasonal effects on magnetospheric convection are not well established for the differing levels of geomagnetic activity. Another 2-day experiment at any time during July, 2000 would satisfy this objective. The widest latitude coverage possible should be obtained, as good time-resolution is not required for building up our statistics.
   Contact: Mike Buonsanto
8. LTCS
   Combined local E and F region measurements, including vector velocities, with 15 minute time resolution. Latitudinal coverage may be sacrificed to meet this goal.
   Contact: Cassendra Fessen
9. CEDAR-TIMED Joint Observations of the Effects of Storms on the Lower Thermosphere
   The goal of this project is to gather observations on the temperature and winds in the lower thermosphere during geomagnetic storms. Data from ISRs and supporting instrumentation available at the upper atmosphere facilities are needed in the primary altitude range of 90-150 km with fine altitude and time resolution (similar to LTCS modes). Data at altitudes in the middle and upper atmosphere will also be useful to study coupling with the lower thermosphere. The observations will be made in response to an alert of a major sustained geomagnetic storm (Kp>5 or 6), and will be studied in coordination with TIMED satellite observations using general circulation and tidal models. A one-month period will be identified one year in advance, and then narrowed to a 10-day stand-by period 6 weeks before the start of the month. The observations will last 4 full days. We request two such periods in year 2000 following the launch of the TIMED satellite (May 2000) and initial validation of its data. The requested periods are for Fall (Sep or Oct) and Winter 2000 (Nov, Dec or Jan 2001).
   Contact: Joe Salah
10. Global Ionosphere-Thermosphere Coupling Study
    All radars should measure electron density, ion and electron temperature and ion velocities parallel to the magnetic field direction. Electric field measurements are not essential for monostatic radars.
    Objectives:
    
    1. Fit and constrain global models of the thermosphere (eg. UCL 3D thermospheric model) and ionosphere (eg. Grenoble TRANSCAR model) using simultaneous measurements at F-region altitudes.
    2. Compute ion-neutral collision frequencies (O-O+) using neutral meridional winds from interferometer and radar measurements. This will include the O-density from the adjusted neutral atmosphere model (from above) and direct neutral temperature measurements where available.
    Both objectives are best studied during quiet geomagnetic conditions. In the case of substorms, however, a study of the global thermospheric response will be possible. All available interferometers near radar sites suitable for thermospheric measurements should be operated. Neutral wind measurements at OID 630 nm are essential. Neutral temperature measurements at OID 630 nm should be done if possible.
    All radars should measure in the magnetic field parallel direction. Electron density, ion and electron temperature and ion velocities parallel to the magnetic field direction are required. Ionospheric electric field measurements are not essential for monostatic radars.
    A long coordinated run is preferred (3-5 days) in order to (1) cover a variety of geomagnetic conditions, (2) measure for extended periods during quiet times to improve the collision frequency estimate and (3) maximise the chance of success due to cloud cover problems for ground-based optical observations. Moon free periods are essential to reduce any optical scattering which can severely affect optical interferometry.
    This experiment was run in February 1999, however, it would be greatly advantageous to increase the data base. This would help confirm any results and provide for better consistency.
    Contact: Mike Kosch and Chantal Lathuillere

[ Home ] [ Search ]

Updated by Tony, Thursday, 05-Aug-99 09:41:00 GMT