EISCAT Scientific Association

Draft Minutes of the 66th Meeting of the EISCAT SAC

RAL, Cosener’s House,in Abingdon, U.K., 22-23 April 2004 (Thu-Fri)

(First draft, 08 May 2004)

Members Present:

Dr. Anita Aikio(Finland, Chairperson)

Dr. Matthias Förster(Germany, Vice-Chairperson)

Dr. Ian McCrea(UK)

Dr. Stephan Buchert(Sweden)

Prof. Tadahiko Ogawa(Japan)

Prof. Cesar La Hoz(Norway, attendance only Friday due to flight delay)

In attendance:

Prof. Anthony van Eyken(EISCAT Director)

Dr. Gudmund Wannberg (Deputy Director, Technical)

Dr. Ingemar Häggström(EISCAT Headquarters)

Dr. Mike Rietveld(EISCAT)

Apologies for Absence:

Dr. Francois Forme(France)

Prof. John Kelly(USA, External Member, absent due to flight problems)

Prof. Eric Donovan(Canada, External Member)

Prof. Liu Ruiyan(China, External Observer)

04/01Preliminaries

The meeting opened at 08:40 pm on Thursday April 22nd, 2004, at Cosener’s House of the Rutherford Appleton Laboratory (RAL),Abingdon, U.K., with Dr. Aikio thanking Dr. McCrea on SAC’s behalf for hosting the SAC meeting. She thanked him also for his efforts and engagement as the outgoing SAC chairman. The chairmanschip had rotatedssince the last meetingthis year. The new ‘chairman’ was now Dr. Aikio from Finland, Dr. Aikio, takes over and the new vice-chairman in turn is was Dr. Förster from Germany. He informed SAC that he enjoys to take overwas pleased to have taken over this role, but it is was very likely that he can could do this job only duringfor athis year because he has had a temporal temporary position at the Max-Planck institute which would terminates by the end of this year2004.

Dr. Aikio had received apologies from Dr. Forme, who was unable to attend the meeting. Apologies for various reasons had also been received also from the External Members Prof. Kelly and Prof. Donovan as well as from the External Observer Prof. Liu. According to an information, passed on by Prof. Van Eyken, Prof. Kelly was stuck at anU.S. airport due to flight cancellations. Prof. La Hoz sended also sent a message informing SAC that he will would be late due to flight problems.

The SAC was pleased to note that Prof. Kelly has had got received an Award of the American Geophysical Union, and it send him cordial congratulations.

04/02Approval of the agenda

The agenda had been circulated electronically in advance and was approved without changes.

04/03Minutes of the 65th SAC Meeting in Uppsala

The minutes of the previous SAC meeting had been circulated electronically among the SAC attendees before the meeting. Prof. Ogawa wondered that onqueried the statement on page 7, (6th line from belowthe bottom), the that 48 hoursof observing timewere available for third party measurements were really agreed upon. Prof. Van Eyken promised to check itthis, but according to his knowledgebelieved that the previous limit ofthe 24- hours-rule of past times were steadily had now been raised to now 48 hours. The minutes were approved thereafter.

04/04Matters arising from the minutes

No new items arose from the minutes.

04/05Report from the 61st Council meeting

The former chairman, Dr. McCrea, attended the 61st EISCAT Council meeting, held on 11-12 Nov 2003 in Copenhagen, Denmark, and he had distributed his report of the meeting via the website. The report is attached as an Appendix to these minutes. He briefly summarised the main points.

04/06Reports on Status and Recent Operations

Dr. Wannberg reported on the status of the radars.

(a)VHF

The situation with the one damaged VHF klystron is was quite worrying. It had been sent for repair to CTL (California Tube Laboratory), but is it now seems seemed likely that CTL may not be able to do the job. The possible options for repair or replacement and their cost estimates were debated thoroughly. The CPI (formerly Varian) facilities in Palo Altohad offered to provide EISCAT with a quote for an inspection of the tube and its possible repair (for an estimated ~100 k$). But for legal (insurance) reasons, there was a possibility that the tube may would need to come back to EISCAT first, to make sure that in order to establish whether any repair made by CTL had been effective CTL haven't repaired it properly. The progress at CTL is appeared, however, to be moving very slowly, and SAC discussed at what point EISCAT might wish to take action to remove the klystron. There was no doubt about the strong scientific arguments to regain full power VHF capability, and in this context it was decided that so that EISCAT should recall againcontinue to keep the situation under close review, and re-evaluate the status after ~about 2 months. At that time, EISCAT could consider removing the tube to CPI, and bearing the additional costs, unless demonstrable progress had been made by CTL.

The possible options for repair or replacement and their cost estimates were debated thoroughly. There was no doubt about strong scientific arguments to regain full power VHF capabilities, so that SAC supports moving the tube to CPI and bearing possible additional costs.

SAC suggests suggested that it was essential to restore the for reasonable costs it is meaningful to get VHF back radar to full power operation, and stressed that, if CTL could not do the job, EISCAT should remove the tube to CPI, and bear the additional costs.

(b)UHF

The situation with the UHF wais generally good, according to Dr. Wannberg's report. New rotary joints have had been installed. There are were still some waveguide problems still, but these were fairly minor (and fixable). It appeared aAminor polariser problem had arisen at Sodankylä. Ultimately, all of the problems with the mechanical polariser would be resolved when EISCAT will moveimplemented to the software polariser.

(c)ESR

The ESR wais working well, and the science support situation wais good, with Vikki Howells from the UK being seconded to work at the ESR site. A letter of appreciation was had been received from Norwegian scientists after their campaign in January, recognising the support which they had recieved.

It was noted that ESR experiments presently can't could not currently receive plasma lines and ion lines line scatter on with the same dish. At the moment, plasmaPlasma line reception is was only possible on the 32m antenna, and j. Joint ion and plasma line experiments are were being run with the two dishes co-aligned.

(d)SPEAR

First The first ESR/SPEAR operations will would start within in the next week following the meeting. There are 4Four members of theLeicestergroup werepeople on Svalbardnow to guarantee propersupport the SPEAR operations next week. The EISCAT/SPEAR joint scheduler is was near to completion now, as based on the EISCAT their scheduling tool, which had been suppliede to the SPEAR team. Relationship The relationship between ESR and SPEAR is was clearly improving. The SPEAR team hadve decided not to buy into the the new cable link, which connected Svalbard to the mainland, however it appeared, but it looks like that no other system couldanfully deliver their bandwidth requirements.. Thismight result in problems for themOne possibility was that SPEAR could still exploit the cable link, via collaboration with. EISCAT, whichmay might get cable capacity at a cheaper rate because of its connection to UiT. And: EISCAT had actually have made an opened opening in their cable connection to allow SPEAR to use it, and hopefully common sense will prevail among all concerned.a sensible solution could be agreed.

SAC was pleased to note the good work being done by the EISCAT staff for on all of the radars.

(e)Heating

Dr. Rietveld summarised his one-page written report.

In particular, he reported in more detail about the possible potential short-term upgrades to Heater beam-forming, phase control and steerability potential enhancement (second paragraph of his report) for relatively cheap upgrades using Direct Digital Synthesis (DDS). This upgrade would give the facility a lot of more flexibility. The DDS improves the beam forming, phase control and steerability. There appears appeared to be a possibility to undertake part of the upgrade using "hot spare" amplifiers from EISCAT at marginal costs. The possibility of upgrading to sSolid-state transmitters was briefly discussed, but because this was a much more expensive undertaking, any such upgrade would be a further upgrade for the future. Because these are expensive, they would have to be part of the futures exercise.

Trees in the antenna area will be cut down in the coming summer.

The tube situation for the heating facilities is was not disastrous. Some of them are were capable of 100 kW, some others 80 kW. Uniform The requirement for uniform power over the whole array meansmeant, one that the available power was limited to that of the lowest-powered tube. has to use the power of the lowest only. A possible future use of VHF phasingthe heating array as a magnetospheric radar was addressed. In this application, transmission would be done:Tx on the high-power array, Rx on a small HF arraywhile the smallest HF array would be used as a receiver.

The Dynasonde was working well, though it was noted that a new generation of advanced ionosondes was being produced in the US, in a project led by Bill Wright. EISCAT should consider buying one of these instruments for Tromso when they appeared. A similar instrument for the ESR site would be highly desirable, possibly on the basis of costs being shared with the new Dynasondes when these things appear from Bill Wright, maybe even in 2005. One should clarify with SPEAR whether one could share the costs of one at ESRfacility.

SAC considers considered the Heating facility and its advantageous location near EISCAT as an important tool for continuing future science studies.

(f)Visiting instruments at EISCAT sites

Prof. van Eyken reported about on the deployment of visiting instruments at EISCAT facilities. An All-Sky Camera (ASC) is had been installed at Tromsø (in Dr. Mike Kosch’s hut) and had been operational since 17 February 2004. It produceobtaindsdata in white light since 17 Feb this year. Imagesimages, whichwill would be available in the near future via the Webweb-site of the CalgaryUniversity. Raw data are were stored locally (not though they would be periodically sent to Canada yet) and amounted to ~1 GByte per day. Real-time images are were available to experimenters on-site.

SAC acknowledges acknowledged the efforts and thanksof its External Member Eric Donovan, and thanked him for installing the ASC.

In March, Prof. Wu from the Chinese Research Institute of Radio Wave Propagation (CRIRP) came to EISCAT to install a GPS receiver at heating. It The receiver was now is working now and EISCAT is was charging a small flat-rate fee for putting hosting GPS receivers at the EISCAT sites. The Chinese researchers are were taking data locally, and have had asked EISCAT to make a CD every month. IIt mayn future, it might also be possible to download the data from the web, though the GPS Rxreceiversis were not yet on the internet. They have aA further one receiver had been installed at Sodankylä, but was not on the EISCAT site there.

A team from The Bath University (UK) is going towould deploy its GPS instruments at all mainland sites in May.

(g)Recent operations

Last years’ operations were presented by Dr. Häggstrom presented a report on 2003 operations. The national shares are were as expected in from the guidelines with one exception: Finland transferred some part its allocation from 2003 to 2004. Slightly more time was run than intended. Satellite Time used in support of satellite operationss time was had been re-allocated to Associates in the correct proportion of their nominal entitlements.

SAC is was happy with the level of operations, and appreciated the job that and under Dr. Häggstrom was doing'sresponsibility, particularly in producing the monthly status reports are in good order.

ThereBecause the EISCAT staff on Svalbard had accumulated a large amount of leave, therewill would be a two-months shutdown at ESR in this summer. Prof. La Hoz noted plans for a possible PMSE campaign in during the summer, but this turned out to be a mainland operation only.

04/07Data Analysis, Archiving, and Distribution

(a)Status and development of GUISDAP

Dr. Häggstrom informed SAC about a new version 8.3 of GUISDAP (v8.3) which had been released running since 3three weeks earlier. It is was running well everywhere at all sites, while its multi-processor capabilities should allow it tobeoperate faster on all systems. The It was noted that the sign convention for the velocities produced by GUISDAPyconventionis was now kept throughout (being opposite to the French and thestandard NCAR convention. The s); the flag “NCAR_vel_pos_away” hadisbeen removed from the GUISDAP output files, meaning thatgone now. But the GUISDAP convention has to the velocityhad to be multiplied by “minus 1” to bring it into line with the NCAR convention. It was noted that theanyrespective plots showing EISCAT velocity data should contain a statement of the sign convention.!

TPresently there weare currently no plans for further upgrades to the analysis tool as yet. Dr. Aikio suggested that a composition fitting would be useful. Dr. Häggstrom replied that the ability to fit for ion composition already existedit is there, but was not yet documented.

Prof. van Eyken reported about on the status of the Madrigal summary database, which now contained data fromwith historic experiments reaching back as far as 1981. Analysed data up to 2004 ware ere now available (some of the most recent data had beenare analysed but were not yet available via madrigal). It appeared that a minimum of available radar data worldwide occurred in ~1995. The Matlab interface to Madrigal data exists now, but there is some trouble with it, regarding firewalls. The link from the schedule page to tape numbers is now redundant and will probably fall into disrepair. Only certain IP numbers are allowed to access the store to control access to SP data.

(b)Calibration, archiving, and distribution of analysed data

Dr. Rietveld summarized the calibration status and a ‘work in progress’ about snowfall influence on radar measurements. The latter effect was revealed by comparing examination of the calibration factor derived from the comparison between Dynasonde measurements of between the NmF2 of Dynasonde measurements andwith radar observations. During a certain interval in September 2003, the

calibration factor went down from values of order 0.8 or 0.9 to 0.66 after a 2cm fall of new snow. On 23-25 October the calibration factor went down to 0.4, after very heavy snowfall. By 31 October, the factor had recovered to 0.9. Further study is would be needed to obtain clarity clarifyabout the effects involved. Plasma line data should be tried asas also be used for cross-calibration.

During the next SAC meeting, aA progress report about this problem should be given during the next SAC meeting.

Dr. Aikio suggested inserting a comment into Madrigal, notingabout the observed effect observed. There was some discussion as to whether the data should be re-scaled to agree with the Dynasonde results, but Dr. Wannberg replied, itssuggested that it was a bad principle to mess withalter the data if one doesn't understand what is going on.unless the nature of the problem was clear.

Calibration of GUISDAP analysed data against Dynasonde results was now being performed regularly, using GIUSDAP is now regularly using RAL's “ui_cal” parametersoftware. Dr. Häggstrom has had implemented the same functionality within a new version of “vizu”, which is was even more convenient.

Prof. van Eyken showed a nice example of foF2 obtained from ESR plasma lines. They The plasma line data weare now available from the ESR web page. Some background subtraction issues are were not yet clarified, but there are this technique offered much promise for good reliable calibration like this of the ESR. In particular, there was a suspicion that data from the ESR . 42m suspected to bewere not well calibrated in GUISDAP, and this should be investigated.

(c)Raw data archiving

Dr. Häggstrom reported about the on the new raw data archiving archive, which had been set up at Kiruna via using a RAID (Redundant Array of Inexpensive Disks) system, which was covered already somewhat by Dr. Wannberg’s TOP before. Since January 1st , 2004, EISCAT had only produces produced only 1 tape copy of data (rather thannot3 three copies as in the pastany more). The data would then go from the disks at the sites, directly to the Kiruna archive. The on-line archive from schedule should still have 1 tape from each experiment. About 1 TByte of raw data is had been accumulated in the archive so far by, downloadinged from tapes, mostly from experiments in 2003. Most CP and some SP data from 1981-2002 had been transferred from RAL,were and converted into the appropriate format. And A there is a tape robot now had been purchased to speed up the process of data ingestion. A problem had arose arisen with different labels of data tapes comingin populating the archive with data from different sources: RAL had organised its data by year, while EISCAT’s SPs SP data holdings are were organised by experiment name. Now it isIn future, the EISCAT archive would be organised by tape name only .