Student-campaign on middle atmosphere phenomena.
Within the course AGF-210 we will have an observational campaign directed at investigating the conditions in the upper part of the middle atmosphere. The campaign will take place mainly in the week 46 but some preparatory work and report writing will be in weeks 45 and 47. This is a version of campaigns that we have been planning for some time and which we have called “Focused Experimental and theoretical STudent Activity” with acronym FESTA. They are planned to be run every year but its content and scientific goal must not be the same each year. This fall the students will run a campaign where much of the instruments located near UNIS, and some at Ny-Ålesund, will be used to collect data on the middle atmosphere. Some of the instruments are run on a routine basis and we will have access to the data, others are especially being run for our purpose. Students will evaluate if data collected from other sources outside Svalbard via internet (Satellite data, magnetometer, ionosonde etc) are of interest and if so, include them in the report.
The Auroral Station in Adventdalen, Norway. Storm-type aurora at 17 January 23:48 UT, 1994.
The instrumentation at the Auroral Station in Adventdalen consists of several optical instruments, devoted to passive monitoring of processes taking place in the middle and upper atmosphere. See station web server for a detailed description of each instrument: http://haldde.unis.no
In the FESTA campaign we aim to use the following instruments:
a) The spectrometers
The Ebert-Fastie spectrometers are scanning target intensities over wavelength. The spectrometers consists of a periscope which can be pointed in any direction in the geomagnetic meridian plane, an entrance slit, a mirror, a grating and a photomultiplier detector mounted on the exit slit. Spectrometers can be used in the UV, visible and IR regions depending on the type of photomultiplier used.
We will mainly use the Silver Bullet spectrometer (zenith view), scanning in the NIR region, to obtain spectra of the airglow. From these spectra we will reduce the temperature from a synthetic fit between measurements and model.
Time resolution: >5 min
Spatial coverage: zenith
Spatial resolution: 5 deg
Spectral resolution: 4 angstroms (7250-8650)
(A) Image of ½ m Ebert Fastie. (B) Optical elements of spectrometer. (1) entrance slit, (2) concave mirror, (3) grating, (4) exit slit, (5) lens, (6) detector and (7) order sorting filter.
b) The Meridian Scanning Photometers
The MSP is a major source of information on the N-S motion of the dayside and night aurora. It scans the magnetic meridian with 5 filter tilted photometers. The activity of the sky is mapped as a function of time along the N-S geomagnetic plane. It can identify the local time position of the ionospheric signatures of the separatrix and the cusp. It is also used in conjunction with the MSP at NYA to determine auroral heights.
Time resolution 16 sec to assemble meridian scan
Spatial coverage: N-S gm meridian (45 deg W of N gg)
Spatial resolution: 1 angular deg.
Spectral resolution: typically 0.4 nm
Channels: 4278 (N2+), 4861(Hb), 5577 (OI), 6300 (OI) and 8446 (OI)
c) The All Sky Video Camera (ALSC)
All sky video frame from the Auroral Station in Adventdalen, Norway 24 December 1995.
This instrument consist basically of a fish eye lens, an light intensifier, relay optics and a video camera. The all sky images obtained in real time is used to get an overview of the auroral activity.
Time resolution: 25 frames per sec.
Spatial coverage: Total Sky
Spatial resolution: 0.5 degree near the zenith
Spectral resolution: VIS
d) The All Sky Imager with Filter Wheel
This camera is constructed as the above video camera, with the exception that an extra filter wheel is added and the detector is cooled to obtained less noise and longer exposure times. We can use the NIR channel to obtain an image of the total all sky airglow emissions. The other channels gives us additional information on auroral morphology etc.
Time resolution: Up to every 10 sec.
Spatial coverage: Total Sky
Spatial resolution: 512x512x8 bits (images)
Spectral resolution: Max 5 bands of 2.0 nm
Channels: 5577 (OI), 6300 (OI) and NIR
2. Eiscat Svalbard Radar (ESR). This radar operates at 500 MHz and can give information on electron density and temperature in the D-layer. It can also give information on wave-activity in the D-layer. ESR will be run for 3 hours each day in week 46 from LT 1300 to 1600. The personnel at Eiscat is hard at work to finalize some of their analysing programs so we will get out the relevant data within a short time after the observations. There are special problems related to these kind of D-layer observations where ground-clutter is the main problem. ESR is being operated by Eiscat personnel and we will have direct access to data.
Overview over student-activities.
The student part of the activity prior to, during and after the campaign will be divided into several parts.
1. The students of AGF 210 will be divided into two groups. Each group will work together throughout the campaign and also write a common report on their results from the campaign.
2. The report must contain a description of processes such as wave activity, wave breaking and heating, precipitation, meteor activity and so on in the region from about 70 to 100 km, which we will investigate.