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Journalof Armospherrc rind TerrrmrulPhysics, Vol.52,No. IO,'1 I, pp. 815-825, 1990. 0021 Y169/9053.00+ .OO Printed m Great Britain. Pergamon Press plc Studies of middle atmosphere dynamics : the research projects Middle Atmosphere Co-operation/Summer in Northern Europe (MAC/SINE), and MAC/EPSILON E. V. THRANE Norwegian Defence Research Establishment and Institute of Physics, University of Oslo, Norway (Received infinal,form 22 May 1990) Abstract-The Earth’s middle atmosphere covers the height region 10~100 km and has been extensively studied in recent years. The international programmes Middle Atmosphere Program (MAP) and Middle Atmosphere Co-operation (MAC) have made significant contributions to our understanding of this part of the atmosphere. This special issue reports on the results from two campaigns, MAC/SINE and MAC/EPSILON, carried out within the framework of MAP and MAC. The two projects both studied the dynamical state of the middle atmosphere at high latitudes and had different, but complementary, aims : 1. Middle Atmosphere Co-operation/Summer in Northern Europe (MAC/SINE) studied the general circulation and temperature structure as well as waves, turbulence and winds in high latitudes during summer solstice conditions. The experiments comprised a series of regular meteorological rocket firings and ground-based observations as well as four launches of sounding rockets. The campaign was carried out in July-August 1987. 2. MAC/EPSILON was a case study of middle atmosphere turbulence by means of instrumented sounding rockets, meteorological rockets and ground-based observations. The campaign comprised four salvoes in which all rocket and ground-based techniques were concentrated in time and space to make detailed measurements during events with strongly developed turbulence. During the campaign period the ground-based techniques were exploited to map the general behaviour of the middle atmosphere during autumn/early winter conditions. The campaign was carried out in October-November 1987. Both campaigns were very successful and yielded a number of significant and interesting results, as demonstrated in the 21 articles in this special issue. I. INTRODUCTION AND OUTLINE The Earth’s middle atmosphere is defined as the region between 10 and 100 km. It comprises the strato- sphere, the mesosphere and the lowest part of the thermosphere, and also includes the ionospheric D- region and lower E-region. The middle atmosphere lies between the dense troposphere where the familiar weather phenomena dominate and the upper iono- sphere and magnetosphere where plasma phenomena and electrodynamic forces are important. Research in recent years has shown that the middle atmosphere is very important in the atmospheric energy budget. It acts as a protective screen for energetic electromagnetic and particle radiation, contains photochemically very active trace constituents and absorbs and reflects radio waves over a wide frequency range. Last, but not least, the middle atmosphere is a region where important and very interesting dynamical phenomena occur. The two projects described here emphasize the study of the dynamics of this region. Recognizing the importance of understanding the physics of the middle atmosphere, the scientific community, under the auspices of the International Council of Scientific Unions (ICSU) and the Scientific Committee for Solar-Terrestrial Physics (SCOSTEP), launched the international Middle Atmosphere Programme (MAP). MAP was scheduled for the years 1982-1985, and was a highly successful vehicle for international co-operation in middle atmosphere research. In fact, interest in the field proved so vig- orous that the need was felt for a continuation of the programme. Thus Middle Atmosphere Co-operation (MAC) was proposed and endorsed, and the projects Summer in Northern Europe (SINE) and EPSILON were approved as projects of MAC. Section 2 describes the scientific aims of the two projects, Section 3 gives a background of previous campaigns and Section 4 briefly reviews the exper- imental techniques. Sections 5 and 6 discuss the two campaigns and their achievements, whereas Section 7 explains the organization of the articles in this special issue. Reference is also made to the Campaign Hand- book [unpublished material, THRANE (19X7)]. 815

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Page 1: Studies of middle atmosphere dynamics: the research projects Middle Atmosphere Co-operation/Summer in Northern Europe (MAC/SINE), and MAC/EPSILON

Journalof Armospherrc rind Terrrmrul Physics, Vol. 52, No. IO,'1 I, pp. 815-825, 1990. 0021 Y169/9053.00+ .OO Printed m Great Britain. Pergamon Press plc

Studies of middle atmosphere dynamics : the research projects Middle Atmosphere Co-operation/Summer in Northern Europe (MAC/SINE),

and MAC/EPSILON

E. V. THRANE

Norwegian Defence Research Establishment and Institute of Physics, University of Oslo, Norway

(Received infinal,form 22 May 1990)

Abstract-The Earth’s middle atmosphere covers the height region 10~100 km and has been extensively studied in recent years. The international programmes Middle Atmosphere Program (MAP) and Middle Atmosphere Co-operation (MAC) have made significant contributions to our understanding of this part of the atmosphere. This special issue reports on the results from two campaigns, MAC/SINE and MAC/EPSILON, carried out within the framework of MAP and MAC. The two projects both studied the dynamical state of the middle atmosphere at high latitudes and had different, but complementary, aims :

1. Middle Atmosphere Co-operation/Summer in Northern Europe (MAC/SINE) studied the general circulation and temperature structure as well as waves, turbulence and winds in high latitudes during summer solstice conditions. The experiments comprised a series of regular meteorological rocket firings and ground-based observations as well as four launches of sounding rockets. The campaign was carried out in July-August 1987.

2. MAC/EPSILON was a case study of middle atmosphere turbulence by means of instrumented sounding rockets, meteorological rockets and ground-based observations. The campaign comprised four salvoes in which all rocket and ground-based techniques were concentrated in time and space to make detailed measurements during events with strongly developed turbulence. During the campaign period the ground-based techniques were exploited to map the general behaviour of the middle atmosphere during autumn/early winter conditions. The campaign was carried out in October-November 1987.

Both campaigns were very successful and yielded a number of significant and interesting results, as demonstrated in the 21 articles in this special issue.

I. INTRODUCTION AND OUTLINE

The Earth’s middle atmosphere is defined as the region between 10 and 100 km. It comprises the strato- sphere, the mesosphere and the lowest part of the thermosphere, and also includes the ionospheric D-

region and lower E-region. The middle atmosphere

lies between the dense troposphere where the familiar

weather phenomena dominate and the upper iono- sphere and magnetosphere where plasma phenomena and electrodynamic forces are important. Research in

recent years has shown that the middle atmosphere is

very important in the atmospheric energy budget. It acts as a protective screen for energetic electromagnetic and particle radiation, contains photochemically very active trace constituents and absorbs and reflects radio waves over a wide frequency range. Last, but not least, the middle atmosphere is a region where important and very interesting dynamical phenomena occur. The two projects described here emphasize the study of the dynamics of this region.

Recognizing the importance of understanding the

physics of the middle atmosphere, the scientific community, under the auspices of the International Council of Scientific Unions (ICSU) and the Scientific Committee for Solar-Terrestrial Physics (SCOSTEP), launched the international Middle Atmosphere

Programme (MAP). MAP was scheduled for the

years 1982-1985, and was a highly successful vehicle for international co-operation in middle atmosphere

research. In fact, interest in the field proved so vig- orous that the need was felt for a continuation of the

programme. Thus Middle Atmosphere Co-operation

(MAC) was proposed and endorsed, and the projects Summer in Northern Europe (SINE) and EPSILON

were approved as projects of MAC. Section 2 describes the scientific aims of the two

projects, Section 3 gives a background of previous

campaigns and Section 4 briefly reviews the exper- imental techniques. Sections 5 and 6 discuss the two campaigns and their achievements, whereas Section 7 explains the organization of the articles in this special issue. Reference is also made to the Campaign Hand- book [unpublished material, THRANE (19X7)].

815

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816 E. V. THRANE

2. GENERAL SCIENTIFIC AIMS OF THE CAMPAIGNS

Both projects studied the dynamical state of the middle atmosphere at high latitudes and had different, but complemental, aims :

SINE studied the general middle atmosphere cir- culation and temperature structure, as well as winds and turbulence at high latitudes during summer sol- stice conditions. The campaign included a series of

regular meteorological rocket firings and ground- based radar and optical observations from 7 June to 19 July 1987. It also included adhoc salvoes consisting of nleteorologi~l rockets and instrumented sounding rockets supported by ground-based observations by radar and lidar.

EPSILON was planned and executed as a series of case studies of middle atmosphere turbulence. The campaign was named after the Greek letter 8, which is commonly used for the turbulent energy dissipation rate. In EPSILON, ground-based and rocket tech- niques were combined to give ‘snapshots’ in time and

space of interesting events. The basic aim was to study the relations between turbulence, waves and wind in the mesosphere. During the campaign period (12

October-l 7 November) four salvoes of this type were launched. In the most spectacular of these salvoes, live instrumented sounding rockets were launched within a period of 80 s.

Both projects were initiated as Ge~an/Norwegian collaborati~Ie campaigns with the Andlaya Rocket Range in north Norway (69’N, 16”E) as the centre

of operations. However, as the planning progressed, international interest in the campaigns grew until a

total of 35 groups in 12 countries actively contributed to the programme. The initial plans were sup-

plemented by both rocket- and ground-based exper- iments from many different stations. Lists of par- ticipants and stations will be given in the following sections.

3. PREVIOUS RELATED CAMPAIGNS

The MAC/SINE and MAC/EPSILON campaigns were the fourth and fifth projects in a series of cam- paigns carried out in Europe to study the middle atmosphere and lower thermosphere. The results of the previous campaigns have also been reported in special issues of the Journ~al nf Atmospheric and Ter-

restrial Physics.

During the winter of 197551976, the Winter Anomaly Campaign was launched from El Arenosillo in Spain to investigate the winter anomaly in iono- spheric absorption (OFFERMANN, 1979). The com- bination of concentrated salvoes with extensive moni-

toring of the lower ionosphere by ground-based

techniques proved very successful, and new, valuable information on the mesosphere and lower ther- mosphere was gained. The results were published in a

special issue [J. atmos. terr. Phys. 41, (lo/l l)]. The campaign showed clearly that transport of minor con- stituents, in particular nitric oxide, NO, determines the ionization rates in the ionospheric n-region in winter at middle latitudes. It is likely that turbulence is a critical factor in the vertical transport of NO (OFFERMANN et al., 1982).

The Energy Budget Campaign was carried out in north Scandinavia during November~D~cember 1980

(OFFERMA~N, 1985). It mapped the energetic processes in the upper atmosphere during different levels of geomagnetic activity. Again the campaign represented a co-ordinated international observation programme, with emphasis on rocket- and ground-based tech- niques. Four rocket salvoes were launched during different degrees of geomagnetic activity. A series of 23 articles describing the results of the campaign were

published [.K atmas. few. Phys. 47, (l-3)]. The results from the campaign made it possibIe to proceed beyond isolated studies of single energy input and loss processes to studies of multiple simultaneous energetic processes and their relative importance.

The campaign ‘Winter in Northern Europe’ (MAP/

WINE) was carried out during the winter 1983-1984 as part of MAP (VON ZAHN, 1987). MAP/WINE ~on~n(rated on middle atmosphere conditions in winter, at high latitudes, with emphasis on winter dynamics and the phenomenon known as a ‘strato- spheric warming’. A stratospheric warming is a sudden temperature increase in the stratosphere (within a few days), associated with a break-up of the winter cir- culation pattern in the polar stratosphere. The causes of the major changes which occur in the mesosphere and lower ionosphere during such an event are not well understood. MAP~WINE was a scientific success. The very large amounts of high quality data obtained from satellite, rocket and ground-based observations provided new knowledge in a number of important areas. These include: the physics of wind shear and turbulent layers in the winter mesosphere, the rate of occurrence and spectral distribution of atmospheric

waves with vertical wavelengths of about 0.1-20 km in the middle atmosphere, the temperature and wind fields during the initial and central phase of a major stratospheric warming, the temperature variations at the mesopause level, and the variations of the con- centrations of minor constituents such as the iono- spheric plasma, water vapour and sodium. The MAP/ WINE results were published in J. utmos. terr. Phys.

49, (718).

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Studies of middle atmosphere dynamics 817

4. EXPERIMENTAL TECHNIQUES

During the MAC/SINE and MAC/EPSILON cam- paigns, a number of different experimental ground- based and rocket techniques were used and, in this section, mention is made of the most important of these, as well as the parameters observed. The tech- niques were combined in different ways throughout the campaigns, as will be discussed in more detail in later sections. A number of rocket systems were used, and Table 1 lists the abbreviations used to describe these systems.

4.1. The ~netet~rolog~caf rockets

These were of three different types :

1. A Viper/ or Stretched Super-Loki/Dart com- bination released a passive falling sphere at an altitude of about 100 km. The sphere was tracked by a pre- cision C-band radar (MPS-36) during its descent and profiles of wind, density and temperature could be derived in the height range 30-90 km. The technique is described by SCH~I~LI~ and MICHEL (1985). Such systems were launched from the Andsya Rocket Range in Norway.

2. A Viper/ or Super-Loki/Dart combination released a cloud of aluminium foil near apogee (82- 107 km). These chaff were tracked by the MPS-36 radar to give very detailed wind profiles, as well as information about turbulence. The systems were launched from the Andsya Rocket Range. The height ranges covered depended both upon atmospheric con- ditions and upon the choice of foil thickness. Typical height ranges would be 75-90 and 85-100 km (WIDDEL, 1985). Again the chaff systems were labelled for the campaigns, as shown in Table 2.

3, From the Soviet ranges at Heiss Island (81”N, 58’ E) and Volgograd (48”N, 46”E), a series of M- 1OOB ~neteorological systems were launched during both campaigns. These rocket systems are quite com- plex and carry a payload which is released from the motor and descends with a parachute. Chaff is released from the payload and tracked by radar. The measured parameters are : electron density (from radio beacon or nose-tip probe, 50-90 km), atmo-

Table 1. Rocket systems and designations

Stretched Super-Loki/Rart (chaff) -CH,‘SSLD Viper 3A/&rt (chaff) -CH/Viper 3A Stretched Super-Loki/Dart (falling sphere) --FS/SSLD Viper 3AiDart (falling sphere) --tS/Viper 3A Nike Orion -N/O Orion -Orion Super Arcas -S/A

spheric wind (from chaff, 60-82 km, from parachute, 20-60 km), pressure (from Pirani heat manometers, 2&70 km) and temperature (from resistance wire thermometer, C-80 km) (PAKHOMOV et al., private communization). Turbulence parameters may be derived from the chaff measurements.

4.2. The instrumented sounding rockets

At the Andtiya Rocket Range, seven different types of instrumented payloads were launched during the campaigns. These payloads contained a large number of instruments designed to study different aspects of the middle atmosphere and lower ionosphere. Table 3 lists the payloads, their designation, the instruments and the responsible scientists/institutions. The prin- ciples of the experimental techniques will be described in the individual papers.

In addition to these rockets, two sounding rockets were launched by the U.S.S.R. from the research vessel Prqj’Zuboc during the SINE campaign. These rockets carried ion and neutral mass spectrometers, and measured in the height range 80-240 km.

4.3. The ground-based techniques

The ground-based techniques were essential parts of both the SINE and EPSILON campaigns. These fell into three different categories :

1. Radar obser~~~t~ons. In north Norway four radars were available during the campaigns. These were the EISCAT radars at UHF and VHF, the University of Tromss HF partial reflection radar and the SOUSY VHF radar at Bleik, near Andenes. In addition to the radars close to the operation centre at AndPrya, there were radars operating at Saskatoon in Canada and in the U.S.S.R. The Saskatoon group also operated an HF drift experiment using the partial reflection radar transmitter at Ramfjord, near Tromsa. Table 4 gives a list of the radars with their locations, frequencies and approximate operation periods. Note that of the many meteor radar stations that operated in the U.S.S.R., only Volgograd and Kazan are included in Table 4, since these stations contributed directly to the results in this issue.

2. Optical observations. The most important optical facility for the two campaigns was the Bonn Uni- versity sodium lidar station at the AndGya Rocket Range. This facility is described by FRICKE and VON

ZAHN (1985). It operated during most of the salvoes. A sodium lidar was also operated at Svalbard (GARDNER et al., 1988). The other optical instruments are referred to in the individual papers. Table 5 shows the location and type of optical measurements oper- ated during both campaigns.

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818 E. V. THRANE

Table 2. Meteorological rocket systems launched from the Andnya Rocket Range and their codes. The chaff systems used foils of different weights : heavy (H), light (L) and super-light (SL). The flights were therefore marked with an extra letter,

for example MAC-E-Cl/L

ESA code

Rocket type

Falliny sphere FS/Vlper 3A

Chajj’ CHiSSLD CHiViper 3A

SINE EPSILON

MAC-S-F1 to MAC-S-F27 MAC-E-l to MAC-E-F4

MAC-S-Cl to MAC-S-C28 MAC-E-Cl to MAC-E-C9

NASA code EPSILON

Project scientist/institution

U. von Zahn/W. Meyer, Bonn University

C. R. Philbrick, AFGL

H. Widdel, Max-Planck Inst. Ae. U. von Zahn. Bonn University

Fallirzg sphere FSjSSLD

TYI-1696 to TYl-1703 F. Schmidlin, NASA Goddard Space Flight Center, Wallops Island, U.S.A.

Table 3. Types and designations of instrumented sounding rockets launched from the Andnya Rocket Range during SINE and EPSILON

Rocket type ESA/NASA code Project scientist

Super Arcas MAC-C-SAI to MAC-S-SA4 J. C. Ulwick. Stewart

N/O BUGATTI IV

MAC-E-T1 MAC-E-T3 MAC-E-T5

Radiance Laboratory, U.S.A.

E. V. Thrane, NDRE, Norway U. von Zahn, Bonn University, F.R.G.

N/O MAC-E-T2 IOMAS II MAC-E-T4

N/O EXERT

Orion MAE

Orion XRG

N/O NEFS

TY2-1694/31.066 GE TY2-1695/31.067 GE

TY I- 1688/30.036 UE TY I- 1689/30.037 UE

TYl-1690130.038 UE

TY2-1691/31.063 UE TY2-1692/31.064 UE TY2-1693/31.065 UE

E. V. Thrane, NDRE, Norway

R. A. Goldberg, NASAIGSFC, U.S.A.

L. C. Hale, Penn. State University, U.S.A.

J. D. Mitchell, Penn. State University, U.S.A.

S. A. Bowhill, University of Lowell, U.S.A.

Instrumentation

Nose-tip electron DC-probe, RF capacitance probe

Positive ion probe. Geiger counter (NDRE, Norway) BUGATTI neutral mass spectrometer, TOTAL ionization gauge (Bonn University, F.R.G.)

Positive ion probe (NDRE, Norway) Positive ion mass spectrometer (MPIK, F.R.G.) Atomic oxygen exp. (University of Stockholm, Sweden) Faraday exp. (Tech. University, Graz, Austria)

Energetic electron detector, thermospheric windjtemp. probe (NASA/GSFC) X-ray detector (Univ. Denver/NASA GSFC) Geiger counter (Univ. Denver) E-field booms, VLF receiver, nose- tip electron probe (Penn. State Univ.) DC pos. ion probe (NDRE. Norway. only in 3 1.066)

Nose-tip electron probe, Gerdien probe, E-field booms, rigid current probe (Penn. State Univ.)

X-ray detector (Univ. Denver/NASA GSFC) Nose-tip electron probe, Gerdien probe, rigid current probe (Penn. State Univ.)

Nose-tip electron probe, drag sensor, accelerometer (Univ. Illinois)

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Studies of middle atmosphere dynamics 819

Table 4. List of atmospheric and ionospheric radars which contributed to the SINE and EPSILON campaigns

Radar

EISCAT

SOUSY

PRE

MF

MF

Meteor radar

Meteor radar

Ionosonde

Ionosonde

Frequency Location

224 MHz Ramtjord 933 MHz (69.6”N, 19.2-E)

53.5 MHz Andenes (69.3”N, 16.O”E)

2.75 MHz Ramfjord (69.6”N, 19.2”E)

2.2 MHz Saskatoon (52”N, 107”W)

2.2 MHz Volgograd (48”N, 46”E)

32 MHz Kazan (56”N, 49’E)

33.3 MHz Obninsk (55’N, 35‘E)

HF Ramfjord (69.6”N, 19.2”E)

HF Andenes (69.3”N, 16.O”E)

Institution Operation period

EISCAT SINE, EPSILON

MPIAe (F.R.G.)

University of Tromso University of Saskatchewan (Norway and Canada)

Univ. of Saskatchewan (Canada)

Centr. Aerological Obs (U.S.S.R.)

Kazan State University (U.S.S.R.)

Univ. of Tromsa (Norway) SINE, EPSILON

Andoya Rocket Range (Norway)

SINE, EPSILON

SINE, EPSILON

SINE, EPSILON

SINE, EPSILON

SINE, EPSILON

SINE, EPSILON

SINE, EPSILON

Parameters

Electron density, winds, turbulence

Winds, turbulence

Winds. turbulence

Winds, turbulence

Partial reflection layers

Winds, turbulence

Electron density

3. Ionospheric observations. The net of stations for

routine observations of ionospheric parameters were essential for the campaigns, both as diagnostic tools for determining launch conditions and as tools to study the physics of the upper atmosphere. Table 6

lists the most important stations providing relevant information for the campaigns.

5. THE MAC/SINE CAMPAIGN

After the very detailed studies of the high latitude middle atmosphere in winter made during previous campaigns, it was natural to emphasize summer con-

ditions. By studying the contrast between summer

and winter conditions, a better understanding of the

processes that determine the seasonal changes may be obtained. The SINE campaign was not, however, planned as a summer equivalent of the complex and

expensive MAP/WINE study, but tried with more simple means to map the most important middle atmosphere parameters.

The summer conditions in the middle atmosphere

are known to be in marked contrast to the winter

conditions. The direction of the mean zonal flow in the stratosphere is reversed and runs from east to

west, the stratopause is colder and the mesopause

warmer than in winter, and the variability of the tem- perature is smaller in summer than in winter. The

Table 5. The most relevant optical experiments operated during the SINE and EPSILON campaigns

Experiment Location Institution

Na lidar

Na lidar

Spectrometer, photometers

Spectrometer

OH spectrometer

OH spectrometer

Andenes (69.3.N, 16.O“E)

Svalbard (79’N, 15 ‘E)

Andenes (69.3”N, 16.O”E)

ESRANGE (68”N, 21”E)

Andenes (69.3-N. 16.0&E)

Andenes (69.3”N, 16.O”E)

Bonn University (F.R.G.)

University of Illinois (U.S.A.)

University of Stockholm (Sweden)

University of Stockholm (Sweden)

University of Stockholm (Sweden)

Utah State University (U.S.A.)

Operation period

SINE after 15 June EPSILON

SINE, EPSILON

EPSILON

EPSILON

EPSILON

EPSILON

Parameters

Na density, temperature density

Na density

Airglow, aurora1 emissions

Aurora1 green line

OH M(8.3) band airglow emissions

OH M(3.1) band airglow emissions

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820 E. V. THRANE

Table 6. The most relevant ionospheric experiments operated during SINE and EPSILON

Experiment

Riometers

Magnetometers

Location Institution Operation period Parameters

Andenes ARR (Norway) SINE, EPSILON Absorption Tromse Univ. of Tromsa (Norway) Finland (chain of Geophys. Inst. Sodankylae stations) (Finland) Kiruna Swedish Inst. Space Phys.

Norway - SINE, EPSILON Magnetic activity Sweden Finland

HF-circuit

Al absorp.

A3 absorp.

North Norway

Volgograd (48-N, 44”E)

Prague

Norw. Def. Res. Est. (Norway)

Centr. Aer. Observatory (U.S.S.R.)

Geophys. Inst. (Czechoslovakia)

SINE, EPSILON Radio prop. conditions

SINE, EPSILON 2.2 MHz absorption

SINE, EPSILON HF, MF, LF abs., phase

seasonal changes profoundly influence the propa- gation of atmospheric tides and waves as well as the transport of heat, momentum and minor constituents. Some of the accomplishments of the SINE campaign

were :

The general circulation of the middle atmosphere at high latitudes during summer solstice conditions

was mapped through a series of regular firings of meteorological rockets combined with radar and lidar observations. The meteorological rockets released chaff clouds and falling spheres, and the radars oper- ated in the HF, VHF and UHF bands.

The middle atmosphere temperature and wind fields, as well as the spectrum of atmospheric waves, were derived from the above observations.

Detailed studies of waves, turbulence and winds were made during some carefully chosen summer events. Four salvoes were constructed for such studies.

The combination of rocket and radar techniques available during SINE proved particularly powerful

for studies of layered structures near the mesopause. The salvoes mentioned above provided very inter- esting new information about such layers.

Tables 7a-7c show lists of the rocket firings from Andsya Rocket Range and from the U.S.S.R. ranges

during SINE. The structure of the salvoes from Andoya is indicated. The salvoes had different designations and launch criteria in order to study different aspects of middle atmosphere dynamics. The criteria are summarized below :

CHAFF SALVOES 24 June. 26 June and 1 Julv. These salvoes were dedicated to studies of detailed wind

profiles (as observed by chaff) and their relation to

waves and turbulence. The main requirement was that the first chaff in the series showed interesting

conditions, such as well-developed wind corners (VON

ZAHN et al., 1985) or wind shears. In addition the

presence of turbulence should be indicated by the

radars (SOUSY, PRE) and the presence of gravity

waves indicated by EISCAT or the Bonn University

lidar. The main criterion was fulfilled for all three salvoes (otherwise the salvo was terminated) ; the sec-

ondary criteria were fulfilled to varying degrees,

depending upon weather conditions (lidar) and iono- spheric conditions (SOUSY).

TURBULENCE/GRAVITY WAVE SALVO 14

July. This salvo combined meteorological rockets with

in situ measurements of turbulence. The launch cri- teria were the presence of strong turbulence (detected

by the SOUSY and PRE radars) and the presence of

gravity waves (detected by EISCAT, PRE, SOUSY and, if clear sky, by lidar). Quiescent geomagnetic

conditions were also required (indicated by mag-

netometers and riometers). All criteria were fulfilled for this salvo.

EISCAT SALVO 15 July. This salvo studied the

relation between EISCAT observations and dynamics observed by meteorological and sounding rockets. A

stable, moderate particle precipitation in the D-region was required, as well as the presence of turbulence indicated by the radars. EISCAT should also indicate the presence of negative ions in the D-region. All launch criteria were fulfilled.

SODIUM/CHAFF SALVO 15 July. This salvo studied the relation between sudden sodium layers (von Zahn et al.) and dynamical phenomena. The

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Studies of middle atmosphere dynamics

Table 7a. Launches from the Andaya Rocket Range during SINE. The rocket system, launch date and time, apogee, success(S) or failure(F) are indicated. The salvo designation and structure

are shown

821

Rocket designation Launch time (UT) Height (km) Comments

ch~i~.~ulr(~ No. I :

S-F1 IS/Viper 3A s-C4jL CH,SSLD s-C5:‘L CH/SSLD Sc6:L CH/SSLD s-c7 L CHSSLD s-C8!L CHjSSLD S-F8 K/Viper 3A

~‘h~~.~~~~~[~ No. 2: S-F9 FWViper 3A s-C9iL Ct-iSSLD s-CIO/H CH,SSLD S-Cl l/L CH,SSLD S-C 12/H CHSSLD S-F10 IS/Viper 3A S-FI I FS:‘Viper 3A

c’!raff’ salw No. 3 : S-F12 IS/Viper 3A s-C13IL CHSSLD S-CI4/H CHjSSLD S-F13 FSiViner 3A S-Cl 5/‘L CcijSSLD S-Fl6/H CHSSLD

Turhukvm/grurity wue salvo. S-SA 1 IL S/A S-F19 FS/Viper 3A SF20 FSiViper 3A s-CI7iL CHjSSLD S-SA2jH S/A s-C18,L CH/SSLD S-Cl9jH CHjSSLD S-F21 SF/Viper 3A S-CZO/L CHSSLD s-C2l!L CWSSLD S-SA3/H S/A s-C22/L CH/SSLD

24 June 1987 I1:OO:OO 1 I :20:00 I1:53:00 12:25:00 12:40:00 13:33:00 13:58:00

26 June 1987 11:OO:OO 1 I :27:00 12:Ol:OO 12:44:00 13:36:00 14:12:00 I I :06:00

1 July I987 21:08:00 21:28:00 22: is:00 23:OS:OO 23:34:00 23:49:00

14 July 1987 08:OO:OO 08:ll:OO 08:32:00 08:52:00 09:29:00 09:43:00 10:19:00 11:02:00 1 I :30:00 N:A I2:03:00 94.0 12:55:00 92.6 13:07:00 N/A

104.7 93.3 94.6

N/A 96.9 98.9

112.0

115.0 94.9

N/A 96. I 86.0

113.4 112.2

112.2 94.7 81.7

112.8 96.0 x4.2

95.4 107.8 114.9 95.3 96. I 96. I 79.9

116.5

criteria were clear sky to allow lidar observations and the onset of a sudden sodium layer. The criteria were

fulfilled.

6. THE EPSILON CAMPAIGN

It seems clear that turbulence plays an important

role in the transport of energy, momentum and photo-

chemically active minor constituents. The name for the campaign was chosen because the Greek letter epsilon (E) is often used as a symbol for the rate of energy dissipation of atmospheric turbulence. The present project concentrated on the height range 50- 120 km. A better knowledge of the nature of tur- bulence at these heights is essential for the modelling of the dynamic and photochemical processes which

determine the state of the neutral gas and the iono- spheric plasma.

The primary aim of the EPSILON campaign was to carry out detailed case studies, concentrated in time and space, of turbulence in the upper atmosphere. Three salvoes were launched specifically to fulfil this goal, whereas a fourth salvo was dedicated more to a study of fluct~tions and electrodynamics in the night- time aurora1 lower ionosphere. A secondary aim was to use the available ground-based techniques to study the general state of the middle atmosphere in late autumn/early winter conditions. In this sense the MAP/WINE, MAC/SINE and MAC/EPSILON cam- paigns make it possible to compare results from three different seasons. Some of the accomplishments of the EPSILON campaign were :

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822 E. V. THRANE

Table 7b. Launches from the Andaya Rocket Range during SINE. The rocket system. launch date and time, apogee, success (S) or failure(F) are indicated. The salvo designation and structure

are shown

Rocket designation Launch time (UT)

EISCA T .sult~o S-SA41L S/A S-F22 FS/Viper 3A s-C23jL CH/SSLD

Sodiunz/chufi’ .sulro s-C24/‘L CHSSLD S-F23 FSWiper 3A SC25;L CH,‘SSLD S-F24 FSWiper 3A s-C26iL CHSSLD s-c27: I CHSSLD s-C28/L CHSSLD

Rqulm Irrunchcs. S-El FSViper 3A S-F2 FS/Viper 3A S-F3 FS/Viper 3A S-Cl/H CHSSLD S-F4 FS/Viper 3A S-F5 FS;Viper 3A S-F6 FSViper 3A S-C?/H CH/SSLD SC3:H CHSSLD s-p-14 FSViper 3A S-El5 FS/Viper 3A S-F16 FSViper 3A S-F17 FS/Vtper 3A S-FIX FSWiper 3A S-F25 FS/Vipcr 3A SF26 FSViper 3A S-F27 FSVipcr 3A

I5 July 1987 12:32:00 97.7 I2:46:00 106.9 13:06:00 97.6

I5 July 1987 20:30:00 95.4 2 I :02:00 117.3 21:17:00 96.9 2 1:43:00 112.6 22:o I :oo 96.6 22:30:00 95.2 22:54:00 93.1

IO June 1987 13:40:00 I2 June 1987 I l:OO:OO I5 June 1987 ll:24:00 I5 June 1987 ll:57:00 I7 June 1987 Il:O3:00 19 June 1987 I1:05:00 22 June 1987 ll:29:00 22 June 1987 12:30:00 22 June 1987 13:00:00 03 July 1987 I 1:OO:OO 06 July 1987 12:40:00 08 July 1987 13:OO:OO IO July 1987 12:12:00 I3 July 1987 19:55:00 I7 July 1987 I 1:OO:OO I9 July 1987 Il:O7:00 I9 July 1987 11:21:00

Height (km)

116.4 115.0 109.0 N,/A 115.0 113.0 114.0 x3.7

N,A 112.1 105.7 108.2 109.5 105.5 112.3 N:A I 15.0

S S S F S S S

;

S S S S S S F S

Table 7c. Launches of MIOOB rocket systems from U.S.S.R. ranges during SINE, 1987

Volgograd (49 N. 44 E)

Time Month Day (UT)

June IO 1526 I7 1630 25 1830 25 2020

Heiss Island (81 N, 53 E)

Time Month Day (UT)

June IO 1905 I3 1905 I7 1905 20 I905 24 1905 27 1905

July I 1534 July I I905 x 1534 4 I905

I5 I526 8 I905 22 I542 I1 I905 22 I740 15 1905 22 1x35 18 1905

21 1905

Detailed ifz situ measurements offine-scale structure and turbulence were made and the relations between gravity waves and turbulence were studied. Energy spectra were derived for a range of scales including

buoyancy waves, turbulence and viscous dissipation. Eddy diffusion coefficients and turbulent energy dis- sipation rates were determined from several stations.

Detailed case studies of winds and waves were made using instrumented sounding rockets. meteorological rockets (chaff and falling spheres) and lidar and radar observations. For example, one of the salvoes was launched through sudden sodium layers near the mesopausc.

The general circulation in late autumn/early winter was mapped using all available data on wind. density and temperature structure obtained during the cam- paign.

The electrical structure of the lower ionosphere dur- ing aurora1 conditions was studied by means of a

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Studies of middle atmosphere dynamics X23

Table Xa. Launches from the Andsya Rocket Range during EPSILON. The rocket system, launch date and time, apogee. success (S), partial success (PS) or failure (F) are indicated. The salvo designation and structure are shown

Rocket designation

Duy suiiv : MAC-E-F I MAC-E-T1 TYI-1690 TY2- I69 I MAC-E-Cl/L TYI-1696 MAC-E-C2/H

TYI-1697 MAC-E-C3SL MAC-E-C4iL

I-c,.sr pi,q/tt I. MAC-E-CSISL

Ni,yizt .who A.

MAC-E-F2 MAC-E-T2 MAC-E-T3 TY2-1694 TYI-1688 TY2- I692 MAC-E-C6SL TYI-1698 TYI-1699 MAC-E-C7/L MAC-E-C&&L

Ni@i sul~o A I.

TYI-1700 TY2-1695 TYI-1701

Test f&g/~ I 2. MAC-E-C9i’L

Night suhw B.

MAC-E-F3 MAC-E-F4 MAC-E-T4 MAC-E-T5 TYI-1689 TY2- I693 TYI-1702 TYI-1703

FSlViper 3A BUGATTI IV 30.038 UE (XRG) 31.063 (NEFS) CHSSLD FSSSLD CHSSLD

I5 October 1987 10:47:00 10:52:00 10:52:20 10:52:40 10:57:00 ll:32:00 ll:33:00

113.5 S 127.0 S 81.0 S

181.0 S 86.7 ~75.5 S

93.4 S 96.3 F (no chaff ejected)

FS’SSLD CHViper 3A CHjSSLD

12:14:00 95.7 13:08:00 113.5 x7.9 I3:32:00 83.9-69.3

CH/Viper 3A I7 October 1987 11:38:00 106.4-85. I

FS/Viper 3A 21 October 1987 21:28:00 112.5 IOMAS II 21:33:00 126.0 BUGATTI IV 21:33:20 125.6 31.066 GE 21:33:40 122.1 30.036 UE (MAE) 21:34:00 89.0 3 1.064 UE (NEFS) 21:34:20 179.2 CH,Viper 3A 21:46:00 101.2 FS/SSLD 22:08:00 89.5 FSjSSLD 22:28:00 90.5 CHSSLD 22:37:00 82.0 CH,‘Viper 3A 23:21:00 102.3

FS/SSLD 31.067 GE (EXERT) FSjSSLD

28 October 1987 00: I I:00 92.0 00:21:00 119.2 00:3 I:00 90.7

CHjSSLD I November 1987 14:30:00 82.0

FS/Viper 3A FS/Viper 3A IOMAS II BUGATTI IV 30.037 UE (MAE) 31.065 UE (NEFS) FSjSSLD FSjSSLD

1 I November 1987 23:58:00 106.8 I2 November 1987 00:16:00 105.2

00:21:00 126.0 00:21:20 124.2 00:21:43 87.3 00:22:22 181.4 00:41:00 95.4 01:01:00 89.X

Launch time (UT) Height (km) Comments

S S S

S

S PS PS S S S

PS S S S S

S S S

S

F S S

PS S S S S

series of rocket measurements, and the morphology of the D-region was mapped by ground-based measurements.

Table Xa lists the rockets launched from the Andsya

Rocket Range during EPSILON and gives an over- view of the salvo structures. The launch criteria and the degree of success in meeting these criteria are given

below. DA Y SALVO, 15 October. This salvo studied tur-

bulence and waves during daytime. In order to make the dynamical features visible to the ground-based radars and to the rocket-borne ion and electron

probes, a particle precipitation event was required,

producing riometer absorption between 0.2 and 2 dB.

Turbulence and gravity waves should be indicated by

the radars and the hdar should have good observing

conditions. All launch criteria were fulfilled. NIGHT SALVO A, 21 October. This salvo studied

turbulence and waves during the night. The launch criteria were otherwise the same as for the day salvo. Night-time conditions gave better observing con- ditions for many of the instruments. All launch criteria were fulfilled.

NIGHT SALVO A I. 28 October. This salvo was

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824 E. V. THRAYE

Table Sb. Rocket systems MIOOB launched from two U.S.S.R. sites during EPSILON, 1987

Volgograd (49”N, 44 ‘E)

Time M~)llth Day (UT)

October 8 1302 14 1530 16 1320 1Y 1235 23 1230 26 1222 28 1610 30 1630

November 2 1204 4 1330 6 0522 9 II52

11 1148 16 1400 18 1600 20 1132 24 1500

Heiss Island (8 1 N, WE) _ .___.____.

Time Month Day JUT)

~-- ..__ -.-- October 12 1905

14 1905 16 190s 19 190.5 21 1905 23 1905 26 1905 2x 1905 30 1905

190s

November 2 1905 4 1905 6 1905 9 2105

11 1905 13 I905 16 1905 1x 1905 20 1905 24 1905

dedicated to the study of the lower ionosphere and upper mesosphere in the presence of pulsating aurora.

An aurora1 event as detected optically from the

ground was required for the launches, as well as par- ticle precipitation in the D-region (riometer absorp- tion between 0.2 and 2 dB). All launch criteria were

fulfilled. ~qIG~T SALVO B, 12 ~o~~~~~b~r. The aim of this

salvo, as well as the launch criteria, were the same as for NIGHT SALVO A. However, weather conditions prevented lidar observations during the salvo.

In constructing the salvo sequences, great care was

taken to make the salvoes as compact in time and space as possible. Note for example that, in NIGHT SALVO A, five instrumented sounding rockets were

launched within a period of 80 s. Table 8b lists the rockets launched from ranges in the U.S.S.R. during EPSILON.

Both from a scientific and technical point of view, the EPSILON campaign has proved very successful. In general, both rocket-borne and ground-based instruments worked well and gave the desired data. The main scientific goals of the campaign were achieved.

7. OVERVIEW OF THIS SPECIAL ISSUE ON THE SINE

AND EPSILON CAMPAIGNS

The experimental studies carried out during the

two campaigns have provided a very large database containing valuable information about the middle

atmosphere. The data analysis is, of course, still in progress at the different laboratories and this special issue by no means covers all the results that have been, or will be, obtained as a result of the campaigns. Some of the analysis is very time-consuming and a series of papers is tentatively planned for a later issue.

In the present special issue the material is organized,

not chronologically according to the two campaigns, but rather according to topic :

The first eight papers deal with turbulence and waves as observed by rocket and radar techniques. The relation between waves and turbulence as

observed in ion and neutral density is discussed. The results suggest that strong turbulence occurs where

gravity waves are most unstable. Comparisons between in situ measurements of irregularities and radar scattering have proved very interesting and fruitful, in particular in the summer mesopause where intense radar echoes from narrow height regions are frequent)) observed.

The next seven papers discuss the wind, density and

temperature structure of the middle atmosphere. The emphasis is on results for high latitudes, but some middle latitude results are included. The available data from rocket and ground-~dsed tecl~niques have

been used to determine the mean state for summer solstice and autumn/early winter conditions. Studies

have also been made of finer scales, such as structures in the sodium layer near the mesopause and of wind ‘corners’ observed by the chaK tccbnique.

The last five papers discuss the electrodynamics of the middle atmosphere and its relation to neutral air structure. Ionospheric routine measurements have been used to map the morphology of the lower iono-

sphere during the campaigns, and rocket techniques have been employed to study the detailed elec-

trodynami~ structure of the D- and lower E-region during the salvoes. The electrical structure of the mid- dle atmosphere is still poorly understood, and both

experimental data and modelling are needed to improve our knowledge in this field. One salvo was dedicated to a disturbed situation with pulsating

aurora.

Acknow/edge~2e~rfs-The Guest Editor would like to thank all the participants in the SINE and EPSILON campaigns for their dedicated efforts, both during the campaigns and in

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Studies of middle atmosphere dynamics 825

the preparation of this special issue. He gratefully acknowl- the editorial work, and last but not least he thanks Mrs edges the assistance of Drs T. A. Blix and U.-P. Hoppe in Maryann Paixao for excellent secretarial assistance.

REFERENCES

FKICKE K. H. and ZAHN U. VON GAKIINEK C. S.. SENFT D. C. and KW~N K. H. OFFEKMANN D. OFFEKMANN D. OFFEKMANN D., BKUECKELMANI’; H. K. G.,

BAKYYETT J. J.. LABI~ZKE K., T~KKAK K. M. and WIUUEL H.-U.

19x5 19X8 I919 19x5 I982

S~HMIULIN F. J. and MICHEL W. R. 1985

WIUDEL H.-U. 1985 ZAHN U. VON 1987 ZAHN U. VON. MEYEK W. and WIUUEL H.-U. 1985

Rczferrnce is crlso made to the following unpublished material:

THKANE E. V. (ed.) 1987

J. utmos. ten. Phys. 47, 499. Nuture 332, 142. J. atmos. terr. Phys. 41, 1047. J. atmos. terr. Phys. 47, I. J. geophyv. Res. 87, 8286.

Proceedings of the 7th ESA PAC Symposium on Euro- pean Rocket and Balloon Pro,yrammes and Related Research (p. 49). ESA SP-229.

Radio Sci. 20, 803. J. rrtmos. terr. Phys. 49, 607. Proceedin.qs of the 7th ESA PAC Symposium on Euro-

pean Rocket and Balloon Programnle.7 and R&ted Rc.veorch (p. 61). ESA SP-229.

Studies of Middle Atmosphere Dynamics : Campaign Hundbook and Campu@ Handbook Supplement ,f& MAC/SINE and MAC/EPSILON. NDRE, Kjeller. Norway.