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APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500024048-2 FOR OFFICIAL USE ONLY JPRS L/ 10279 25 January 1982 Translation PHYSI~A~ METHODS FOR INVESTIGATIN~ iCE AND SNOVI~ Ed. c~y V.V. Bogorodsk~iy an:d V.a. Spitsyn _ FOREIGI~ BROADCAST INFORMATION SERVICE FOR OFF[CiAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2407/02109: CIA-RDP82-00854R000500020048-2 NOTE JPRS publications contain informatiion primarily from foreign newspapers, periodicals and books, but also from news agency transmissions and broadcasts. Materials trum forei~.~-language sources are translated; those from English-language sources are transcribed or reprinted, with the original phrasing and other characteristics retained. Headlines, editorial reports, and material enclosed in brackets are supplied by JPRS. Processing indicators such as [Text] or [ExcerptJ in the first line of each item, or following the last line of a brief, indicate how the original information was processed. Where no processing indicator is given, the infor- mation was summarized or extracted. Unfamiliar names rendered phonetically or transl.iterated are enclosed in parentheses. Words or names preceded by a ques- tion mark and enclosed in parentheses were not clear in the original but have been supplied as appropriate in context. Other unattributed parenthetical notes within the body of an item originate with the source. Times within items are as given by source. The c~ntents of this publication in no way represent the poli- cies, views or attitudes of the U.S. Government. - COPYRIGHT LAWS AI~TD REGULATIONS GOVERNING OWNERSHIP OF MATERIALS REPRODUCED HEREIN REQUIRE THAT DISSEMINATION OF THIS PUBI,ICATION BE RESTRICTED FOR OFFICIAL USE ONLY. APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 FOR OMFICIAL USE ONLY JPRS L/10279 - 25 January 1982 - FHYSICAL METHODS FOR INVEST~GATING ICE AND SNOW Lening~rad T'_'.UDY. ORDENA I,ENINA ARKTICHESKIY I ANTARKTICHESKIY NAUCHNO- - ISSLEDOVATEL'SKIY INSTITUT. FIZICHESKIYE METODY ISSLEDOVANIYA L'DA I SNEGA in Russian No 326, 1975 pp 2-23, 51-54, 74~79, 90-93, 104-120, - 143-146 [Annotation, table of content:~ and selected articles from collec~ion "Physical Methods for Investigating Ice and Snow", edited by V.V. Bogorodskiy, doctor of physical and mathematical sciences, and V.A. Spi.*_syn, candidate of physical and mathematical sciences, Gidrometeoizdat] ~ CONTENTS Annotation 1 Table of Contents 1 ~ ' Preface 4 Radiophysical Methods for Itivestigating Ice and Snow (V. V. Bogoroc~skiy) 6 Ra.dar FM Signals Reflected From Ice Surfaces and Possibilities of - Zheir lrbdeling - (A. B. Eaba;ev, et 13 Influence of Ice Structure on Its Radiation Characteristics in the SHF Ran ge _ (A. Ye. Basharinuv, A. A. Kurskaya)..... 18 - Reirote Measureme:~t of Sea Ice Thickness by Radar rlethods (M. I. Finkel'shteyn, et al.) 21 ~ Instrumentation for Investigating Spectral Reflection of Liquid Water 1_n the Wavelength :legion i-SOiu m (M. A. Kronoticin) 25 Ice Behavior in High-Strength Rapidly Varying Elertroroagnetic Fields (L. B. Nekrasov)......... 31 - a- jI ~ USSR - E FOUO] FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/42/09: CIA-RDP82-00850R000500020048-2 FOR OFFICIAL USE ONLY Dynamics o~ Ice in Coastal Reginns According to Data From Side-Looking Padar Survey From Aircraft (S. M. Losev, Yu. A. Gorbunuv) 35 Observations of Sea Surface Temperature Using a Radiation Zheauometer From an Ice Reconnaissance Aircraft (A. I. Paramonovy et al.) ............................................n. 44 Study of Dynamics of Glaciers Using Iaser Deformograph (I. M. Belousova, et al.) 51 - b - - FOR OFFIC[AL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02/49: CIA-RDP82-40850R040500024048-2 FOR OFFICIAL USE ONI.Y ~T~Xt~ Annc~t.ition. T}lis collection of artic].es includes materi.~l~ f.rom r~ gci.entific. ~ :;ymposl_um orKanized by tiie Order of Lenin Arctic and Antarctic Scientific Researc'.: Institute and the Interdepartmental Commission on Study of Antarctica, Earth Sci- ences Section, Presidium, USSR Academy of Sciences, heZd in Leningrad, 1-5 Octota~r 1973. The articles by Soviet and foreign scientists reflect the results of investi- gations of rzcent years in the following directions: 1. Electrotnagnetic methods for - investigating snow and ice, active and passive radar observations of ice and snow - surfaces. 2. Optical methods for investigating snow, ice and water. Dynamic and ' static methods f~r investigating the dynamic pt:perties of ice and snowo Contents Original page PreEacz 7 . Bogorodskiy, V. V., "Radiophysical Methods for Investigating Ice and Snow"...... 9 - Babayev, A. B., Logachev, V. P., Parfent'yev, V. N., Fedorov, V. A, and Shemo- manova, G. P., "Rac:ar FM Signals c~eflected From Ice Surfaces and Possibilities ~ of Their Pionitori~.lg~~ ..........................................................17 Pasfiarinov, A. Ye. and Kurskaya, A. A., "Influence of Ic2 Str~scture on Its Radiation C'haracteristics in the SHF Range" 21 Bogorodskiy, V. V., Trepov, G. V. and Fedorov, B. A., "Radio Wave Propagation in Glaciers" 24 Bogorodskiy, V. V. and Tripol'nikav, V. P., "Radio Echo Sounding of Sea Ice"... 29 Bogorodskiy, V. V., Kozlov, A. I. and Tuchkov, L. T., "Emissivity of Ice, Land and Sea Surfaces Simulated by Layered-�Inhomogeneous Structures" 32 Clou~ti, J. LJ., "Measuren~ents of Reflected Signals in Radio Echo Sounding in a Large Range of Anf,'~,5~~ 39 Clc~u~;li, J . W. , "Depolari za,_lon of Reflected Radio Signals". . . . ~ . . . . 45 Finkel'sht~yn, Ti. I., Kuta;ev, V. A., Glushnev, V. G. and Lazarev, E. I., "Remote Measurement of Sea Ice Thickness by Radar Methods" 51 7.liebrovskiy, A. K., Strakhovskiy, G. M., Nedostayev, V. N. and Stebin, V, I., "~lectric Yroperties o` Ice Formed in Vacuum ar?d Their Interrelationship to Str.t?cture" 55 - 1 - FOR OFFYCIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/42/09: CIA-RDP82-00850R000500020048-2 FOR O~'FICIAL USE ONLY Vershinin, S. A., Kopaygorodskiy, Ye. M., Yanov, V. V. and 5hvayshteyn, 'L. I., "Ice Pressure on Separately Standing Supports According to Labrator.y and - In Situ Tests"........~ 59 Dav=s, lI. and Munis, It., "Correlation I3etween t}ie Salir.ity of Sea Ice and Exti.nction of Light With Waveler~gr.h 6328 A" 66 Gaytskhoki, B. Ya., "Optical Characteristics of Some Varieties of Natural Ice".. 71 Kr~potkin, P4. A., "Instrumentation for InvestigaLing Spectral Reflection of Liquid Water in Region of Wavelengths From 1 to 50 � m" 74 Petera, V., "On Study of the Process of. Charge Formation on the Phase Discontin- uity Directed Toward a Freezing 10-3 Molar Solution of Sodium Chloride"....... 80 - Nekrasov, L. B., "Ice Behavior in a Highly Variable High-Strength Electromagnetic Field" 90 Volod'ko, B. V., Yakupov, V. S., Aklimedzyanov, E, N., Kalinin, V. M., Papitash- vili, V. 0. and Sereda, G. A., "Magnetic Survey of Reformed Vein Ice"......... 94 - MeI'nikov, V. P. and Snegirev, A. M., "Low-Frequency Polarization of Ice and Frozen Coarsely Disperse Formations" 99 - Losev, S. i~i. and Gorbunov, Yu. A., "Dynamics of Ice in Coastal Regions According to Data From Side-Looking Radar Survey From Aircraft" 104 P3ramc~nov, A. I., Gorbunov, Yu. A. and Losev, S. M., "Observ3tton of Sea Surface � Temperatur? Using a Radiation Thermometer From an Ice Rec~nnaissance . Aircraft" ...............................................o.................... 114 Gavrilo, V. P. and Gusev, A. V., "Use of Acoustic Methods for Investigating Snow and Ice"..... 121 _ Bogorodskiy, V. V., Smirnov, G. Ye. and Smirnov, S. A., "Absorption and Scattering of Acoustic Waves by Sea Ice" 128 Grubnik, N. A. and Kudryavtsev, 0. V., "One Method for Measuring Sound Atten- uation in Natural ~ce" 135 Smirnov, V. N. and Lin'kov, Ya. M., "Seismic and Tiltmeter Methods for - Investigating the Ice Cover" 137 Belousova, I. M., Ivanov, I. P. and Firsov, N. G., "Study of Dynamics of ' Glaciers Using Laser Deformograph" 143 - 2 - , FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 FOR OFFICIAL 'JSE ONLY 7 P;inov, V, V., Panyushkin, A. V., 5inochkin, Yu. D. and Shvayshteyn, Z. I., "Experimenta~ Study of Ice Adhesion Under Laboratory and In Situ Conditions". 147 ~ C;rubnik, N. A., Fomin, V. I. and Shemyakin, A. B., "Study of the Process of Destructian of an Ice Layer" 155 Vuori, A. F., "Piechanical Properties of Snow as a Construction Material"....... 157 Dolgin, I. M., Bryazgin, N. N, and Petrov, L. S., "Snow Cover of the Arctic"... 165 Avdyushin, S. I., Barabanshchikov, R. M., Kogan, R. M., Kulagin, Yu. M., Nazarov, I. M., Fridman, Sh. D. and Yudkevich, I. S., "Method for Measuring Moisture Reserves in the Snow C~ver Using Cosmic Radiation" 171 Abel', G., "Mettiods for Measuring ttie Strength Characteristics of Natural and Processed Snota" 176 ~ i3uzuyev, A. Ya., "Statistical Evaluation of Spatial Distribution of the Principal Parameters of the Ice Cover" .............................a......... 187 ICorzhavin, K. N. and Ivchenko, A. B., "Investigation of Mechanical Properties of Fresh-Water Ice Witl~ Sluw Changes in Load" 193 ' 'l.aretskiy, Yu. K., Fish, A. M., Gavrilo, V. P. and Gusev, A. V.y "Pi�oblems ia ~ Short-Term Creep of Ice and Kinetics of Formation of Microfissures".......... 197 _ Ryvlin, A. Ya., "In Situ Investigations of Physicomechanical Properties of Ice Cover".....~ .........................................o................... 205 Kheysin, D. Ye., Likhomanav, V. A, and Kurdyumov, V. A., "Determination of Specific Energy of Destruction and Contact Pressures With Impact of Solid Body an Ice" 210 - I3ogorodskiy, V. V., Gavrilo, V. P. and Polyakov, A. P., "Radiohydroacoustic t~tethod for. Using Mesoscale Characteristics of Dynamics of Sea Ice"........... 219 - 3 - F'OR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 FOR OFFICIAL USE ONLY PREFACE Leningrad TRUDY. ORDENA LENINA ARKTICHESKIY I ANTARICTICHESKIY NAUCHPdO-ISSLEDOVATEL'- SKIY INSTITUT. FIZICHESKIYE METODY ISSLEDOVANIYA L'DA I SNEGA in Russian No 326, 1975 pp 7-8 [Unsigned article] ~ [Text] This collection of articles contains studies devoted to physical methods for the investigation of ice and snow. It can now be assumed th~t a new direction has already been formed in glaciology the physics of ice. - Taking into account the increasing interest in physical methods for investigating ice, the Arctic and An*_arctic Scientific Research Institute and ti~e Interdepart- mental Commission on Study of Antarctica organized a special symposium which was held in October 1973 at Leningrad. Most of the reports nresented at the symposium were finalized in the form of articles which have been published in this. collection - of articles. The articles presented in the collection reflect the resnlts of investigations of = recent years in the following directions: Z. Electromagneti~ methods for investigating snow and ice. Active and passive radar of ice and snow covers. - 2. Optical methods for investigating snow, ice and water. 3. Dynamic and static methods for investigating the mechanica~ properties of ice and snow. Many of the artic?as are devoted to the results and methods for investigating the mechanico-acoustical properties of ice and snow. The importance of further investi- gations in this direction is demonstrated, especially determination of the charac- teristics of internal friction, the coefficients of absorption, viscosity, velccit- ies of propagation of wave processps, reflecting and scattering properties in a broad range of amplitudes of deforraations and frequencies of elastic and visco- elastic oscillations (seismic range, infralow-frequency, acoustic and ultrasonic frequencies -10-2-106Hz). ~ Recently investigations have been initiated o� dynamic phenomena and the stressed state of the ice covers of different ~cean areas by seismoacoustic methods and also methods based on the use of lasers. 4 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 FOR OFFICIAL US~ ONLY Ttie studies made in these three directions. reflected new results of investigati~ns ~atiich are a considerable contribution to the physics of ice. These results bring considerably closer the sotution of highly important physicotechni~al problems related to artificial modi~ication of ice and snow (radar observation of aea ice, problems of ice destruction, evaluation of the stressed states of the ice covers by the laser and seismoacoustic me*hod, remote determination of large moisture re- serves in the snow cover, etc.). COPYRIGHT: Arkticheskiy i antarkticheslciy nauchno-issledovatel'skiy institut (AANII), 1975 . - S FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02/49: CIA-RDP82-00850R440500020048-2 FOR OFFICIAL USE ONLY RADIOPHYSICAL rir.THODS FOR INVESTIGATING ICE .AP?D SNOW Leningrad TRUDY. ORDENA LENINA ARKTICH~SKIY I ANTARKTICHESKIY NAUCHNO-ISSLEDOVATEL'- SKIY INSTITUT. FIZICHESKIYE METODY ISSLEDOVANIYA L'DA I SI~EGA in Russian No 326, 1975 pp 9-16 [Article by V. Bogorodskiy] ~ [Text] Ice, one of the physical bodies occurring most widely over the surface of our planet, is an exam?ale of a proton dielectric, a viscoelastic body, capable with ~ relatively sraall change in external conditions of changing its micro- and macrastructure, electric and mechanical properties. Continental and mountain glaciers are sources of pure water and the principal water resour,ces for irrigation in arid regions. The glaciers and ice covers to a consid- erable degree are regulators of weather and climate. At the same time, glaciers and ice covers on~the seas are features creating dangerous natural phenomena. The shelf of arctic seas and regions of permafrost in Siberia constitute rich ware- _ houses of natural resources. Their exploitation is determined by the possibility of overcoming of the ice, that is, its destructi~n, or use as a material. Both these aspects lead to the need for studying all the properties of ice and snow. The diver- ~ sity of problems favored the formation of an independent direction in ice investiga- tions (not only as a substance, but also as a geophysical feature), ice physics. The physics of ice as a science has already attained considerable successes in the - study of the atomic-molecula~ structure of .ice, the behavior of protons in hydrogen bonds and lattice dynamics. This has been facilitated by ti~e work of Professor Granicher (~witzerland) and Doctor Wall (~Canada). Important investigations have been carried out for studying the growth of ice crystals and their orientation by N. P. Cherepanov and P. A. Shumskiy (USSR), Doctor Hobbs and Doctor Kitcham (United States). . However, in ice physics there are a number of problems which until now have only been formulated. From our point of view such important ~roblems include the ther- moelectric effect of ice, potential jump at the boundary of development of phases and precipitation of impurities during the growth of ice crystals from a melt and solution. The investiRation of the processes of thermoelectricity and potential jump, to be sure, in the long run will lead to aa evaluation of the possibiYity of using the energy of the discussed phenomena. At the present time quantitative 6 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 FOR OFFICIAL USE UNLY estimates are already being given for the thermoelectric potentisl gradient and the potential gradient at the ice-water discontinuity, atta~ning several tens of volts. Primary laboratory investigations show that these phenomena are in fact singular natui:al generators of electric energy. Investigations of the influence of impurities on ice structsre are very interesting. It has been established that exceedingly small quaritities of impurities (1~, HF) in virtually every case bring fresli-water ice close in its properties to sea ice. Pene- _ trating between the crystals, in many cases they give a complex structure with vari- able salinity and the presence of small volumes of saline water. Such a structure is the subject of intensive study b~ physicists: it is responsible for the mechan- ical and electrical properties of ice. A comprehension of the physical principles of the growth of crystals ir. the presence of impurities is of great importance in - developing reliable methods for ob*_aining drinking water from the sea by means of . _ its ~reezing. The problems of atomic-molecular physics of ice were discussed more - completely in [4]. Tn this article we examine s~me problems related to study of the electromagnetic characteristics of snow and ice (including the optical and mechanical properties of snow and ice and dynamics of the ice covers). The availability of these data makes it possible to solve a number of serious prac- tical problems: creation of radio equipment for sounding ice covers, study of the functional dependence of the mechanical characteristics of ice, conditions for the transfer of radiant energy thrcugh ice covers, measurement of the rate of movement of ice covers and evaluation of their stressed state. Electromagnetic Characteristics of Ice and Radia Probing of Ice Co�~~rs ~ During recent years specialists in the USSR, United States, Denmark, Canada and Japan have carried out extensi~~e laboratory and field investigations of the elec- - tromagnetic characteristics ~ and tg b of glacier, fresh-wat~r and sea ice in a ' broad range of frequencies from i00 Hz, including optical. The generaliz~tion and analysis of theoretical and experimental data on ele~tromag- netic characteristics mude it possible to create reliable radio apparatus for study of the structure (t}~~c_kness, layering, inhomogenei~y) and state (mean effective temperature) of coiu, moder~re and warM glaciers. Using radio spparatus created in Great 33ritain, Denr~ark, ~SSP. and the United States and installed on different _ carriers, new possibilities appeared for the study of the ice shields of Antarctica, Greenland, the Arctic and other glaciers of our planet. An important conclusion drawn as a result of raciio measurements is a new idea con- cerning the thickne~s of glaciers and the structure of Antarctic relief beneath the ice. Figure 1 shows that tlie relief of Antarctica beneath the ice i~ not sr.?oothed (for example, in the zone of tlie Soviet investigations), as was speculated before, but instead has abru~t dropoffs and mountains with sharp peaks. Radar r~akes it pos- sible to refine map~ of ~'lntarctic relief. It is interesting that a detailed radar survey of tlie polygons also revealed a very great diversity of relief. Interesting results from radar probinp, of this type were obtained by researchers at the Scott 7 - FOR OFFICIA~. USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 FUR OFRICIAL USE ONLY Institute (Cambridge) and thc Professor Gudmandsun Laboratory (Denr.iark). � Table 1 Electromagnetic Characteristics of Some t4edia Piedium Velocity, m/U-sec Specific ab- Measurement ~ soi�ption f = conditions 30 MHz Cold glaciers 164 0.065 at -40�C - 169 0.025 at -10�C iJarm glaciers 169 0.05 at -1�C 169 0.035 at -5�C Perennial perulafrost 110 1-8 at -5�G - 0.4-2.5 at -15�C Fresh water bodies 33 0.5-2.5 Sandy ground 170 0.05 dry 55 2 moisture con- tent 30% Sea pack ice 150 1-2 at -20�C thickness 2-9 m Young sea ic~ 100 3-5 at -20�C ~ thickness 0.9- 1 m A more complex cycle af ineasurements of the electromapnetic characteristics of sea ~ ice in the SHF range led to the solution of an equally important problem the fundamental possibility of remote measurement of thickness of drifting sea ice. In the USSR this problem was solved by the scientific personnel of the Arctic and Ant- arctic Scientific Research Institute and the Institute of Civil Aviation Engineers (Riga). At the same time this sar~e problem was solved by researchers in the Unitad States, Canada and llenmark. _ Radio sounding of glaciers and sea ice was facilitated to a considerable degree by radio sounding of highly absorbing media: desert sands for the detection of water- Uearing layers, fresh-water bodies and permafrost. - Table 1 gives the electromagnetic characteristics of highly absorbing media. They show that it is possible to employ radio apparatus for soundin~ these media. Fluctuations of Radio Signals in Probing of Ice Covers. Depolarization of Radio Waves in Glaciers The nonuniformity of ice covers and the complex structure of the underlying bed change the amplitude, phase, shape~of envelope, lag and polarization of the stud- - ied radio signals. A statistical analysis of the random process of change in the signal amplitude, which is determined by the differ~nt influence of scatter3ng on the surface of the glacier and its bed, is of interest in estimating the rate of its movement. A mass of data on fluctuations of amplitudes made it possible to _ 8 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 FOR OFFICIAL tJSE ONLY compute the autocorrelation radius~ and demonstrate its direct de~endence on the radiated frec;uency. ti5 60 55 SU 6g ~ , ~ ~s 145 I I O I ZMr I I ~ Y ` / ~ - / ~ 9, , ~ ~ ~ao r r ~ so ~ ~ ~ : ~ \ ~i ~ ~ , ; ` ~ . ~ ~ 35 ~ ~ ' j' O ~ . ~ 55 \ / , _ ee / . Monoae~Naa ' ' _ � I Cee i . . . I ~ 50 45 40 36 , Fig. 1. Profi~es of relief under ice along radio sounding ~>roriles. In upper left corner vertical scale. - Figure 2 illustrates the fluctuations of signals reflected by the glacier bed for frequencies of 440, 213 and 60 Mliz. These frequencies correspond to autocorrela- tiun radii of 0.8, 1.6 and F.1 m respectively. The frequency dependence of the - autocorrelation radius of t~ ~tuations of amplitudes can be used in measuring the - rate of movement of glaciers in any regions of Antarctica. In the USSK much cvork has been done on studying the phenomenon of depolarization of electromagnetic waves during their vertical propagation in a glacier. Similar investigations are being made by Clough (in the United States). Our studies indi- - cated that one of the principal reasons for depolarization is double refraction. Ice Optics RecentJ.y extensive use has been made of optical methods for investigating ice. This has bee;~ dictated by the timeliness of those scientific and practical problems = which they make it possible to solve. Investigations of the interaction of optical 9 ~ FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 FOR OFFI~IAL USE ONLY radiation with ice are being carried out in a wide range of wavelengths, including both the visible and IR parts of the spectrum. Infrared spectroscopy of ice made it possible to take a considerable step forward in the study of its molecular struc- ture and to reveal a great diversity of structural forms. U a i.o a o.e o.a o.~ � - o.s oL---- - ----f-- ---I ' b 2 ~ . ~ O - - ---~'y-.. ----1 C 3 B 2 I O - --------T�- ao M Fig. 2. Distribution of amplitudes of reflected signals for frequencies 440 MHz ' (a), 213 PiHz (b) and 60 MHz (c). The problem of radiation transfer through the snow and ice cover of water areas is acquiring particular importance. The energy penetrating through the ice is consid~ erably attenuated and greatly changes the character of tYie underwater light field, and accordingly, biological activity and the conditions for the use of different _ optical systems for underice visibility and other problems. It stiould be noted that an estimat,e of the total attenuation of optical radiation during transmission through the ice involves great difficulties. The scattering in- dicatrices for ice are very diverse. They are indicative of the complex scattering properties of ice structure. ' Mechanical Characteristics of Ice and Stressed State of Ice Covers. Movement of Glaciers - 10 FOR OFFICIAL USE ONY.Y APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02109: CIA-RDP82-00850R400500020048-2 FOR OFFICIAY. USE ONLY The study of the mechanical properties of ice and snow is an important problem ~ahich is now being solved by the scientists of Canada, USSR, United States, Great Britain and Japan. The increased interest in this problem is obvious: in the study or exploitation of polar territori~s and ocean areas it is necessary to improve the types of transportation and either destroy the ice or use ~t as a construction material. In both aspects the success is determined by a knowledge of the mechan- ical characteristics of the ice and snow obtained by dynamic and static methods. A study of the mechanical properties of ice in combination with the packing of its macrocrystalline structure made it passible to estimate the strength charac- teristics of sea and fresh-water ice freezing under. different hydrometeorological conditions. The acoustic method for studying the mechanical characteristics.of ice has been found to be promising. This method, not destroying the investigated medium, malces it possible to make measurements in individual crystals, blocks and the ice cover. ~ Ttie mechanical characteristics oUtained by an acoustic metliod made it possible to develop a method for predicting their distribution in the thickness of the ice cover, knowing the air temperature. At the present time for further progress in this field it is necessary to have - n.e~a theoretical models reflecting the state of ice in response to rapid and slow etfects and taking into account the thermal oscillations of atoms and molecules, and also the developing changes in the structure of the bonds among them during deformation. An equally important problem is study of the stressed state of ice covers. At the Arctic and Antarctic Scientific Research Institute specialists are developing two directions toward its solution: study of the sound emission of deforming ice and ~ use of special Doppler laser systems. Similar work is being carried out by Profes- sor Bentley in the United States. The principal aspect of this problem is a deter- mination of the numerical values of the developing pressures and their quantita- tive and qualitative correlation with hydrometeorological conditions. Information of this character would facilitate prediction of the stressed state of ice and es- pecially the moments of its destruction, However, this problem is considerably - complicated by the strong dependence of the physical properties of ice on many factors, the ~ariability of the thickness of drifting ice, the absence of satisfactory tnodels for :rediction of macroscale deformations and the drift of ice on the basis of the me~~ured hydrometeorological parameters. The intensity of the acoustic emission and the parameters of the acoustic signals radiated during the deformation of ice can be a key to solution of the problem. It has now been estaol.ished that the amplitudes of the oscillations, the spectral composition of waves, their velocity, duration of pulses and their repetition - rate are objective criteria determining the general character of stages of the stressed state. It was also found that this information is carried by oscilla- tions with a broad SPectrum of frequencies from 10-2 to 106 Hz. However, there is also a definite selectivity: at the temperatures of critical stresses the maxi- mum of the acoustic emission spectrum for ice falls in the band 100-400 Hz. The first in situ experiments revealed the good prospects of the acoustic method for - determining the stressed state of the ice cove-r. The correlation coefficient be- tween the regis~ered acoustic emission and air temperature fluctuation was about 0.8 [1, 2]. 11. FOR OFF[CIAY. USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 FOR OFF(CIAL USE ONLY The use of lasers also makes it possible tQ make estimates of the stressed state - of ice covers. The preliminary experiments carried out on the ice of Lake Ladoga in the winter of 1972 made it possible to obtain the numerical values of stresses in the ice [3]. The physical hasis for Qstimating stressed state by this method ~s _ the possibility of determining the deformation of ice under the influence of some factors. The Doppler laser method applicable to this problem shows that the deter- mined deformation, multiplied by the dyna~nic modulus, leads to an evaluation of ' the stressed state. The study of glacier movement is a timely problem for whose solution there is a good theoretical basis [5, 6]. Some progress has also been noted in the experimental investigation of glacier movement: the basis for this progress is laser poppler systems, the scattering properties of the glacier bed and a detailed radio survey of oriented polygons. The Arctic and Antarctic Scientific Research Institute, in collaboration with the State Optical Institute imeni Academician S. I. Vavilov, has developed special laser systems known as deformographs; these tiave undergone testing in Antarctica. These tests revealed that laser apparatus with a high degree of accuracy can register the absolute and relative rates of glacier movement. At the Arctic and Antarctic Scientific Research Institute experiments have begun on study of the movement of glaciers relative to '_rregularities of'the bed under the ice. We already have qualitative confirmations of a partial realization of this - idea. The essence of the method is a repeated (with a definite time interval) de- tailed radio survey of the relief under the ice in polygons whose coordinates were determined with a high accuracy. A survey of these polygons repeated alter a year demonstrated the presence of a complex displacement of the glacier. BIBLIOGRAPHY l. Bogorodskiy, V. V. and Gavrilo, V. P., "Physical Methods for Investigating the Stressed State of the Ice Cover," TRUDY AANII (Transactions of the Arctic and Antarctic Scientific Rese~rch Institute), Vol 316y pp 59-69, 1974. 2. Bogorodskiy, V. V., Gavrilo, V. P. and Gusev, A. V., "Acoustic Effects in the Friction of Ice," TRUDY AAPlII, Vol 324, pp 97=103, 1975. 3. Bogorodskiy, V. V., Gavrilo, V. P. and Ivanov, I. Pe, "Use of the Doppler Effect in Lasers for Investigating the' Stressed State of Ice," TRUDY AANII, Vol 324, pp 114-117, 1975. 4. FIZIKA L'DA. OBZOR DOKLADOV MEZHDUNARODNOGO SIt~OZIUMA PO FIZII:E L~DA, SOSTOYAV- SHEGOSYA 9-14 SENTYABRYA 1968 V MYUNKHENE (Ice Physics. Review of Reports at the International Symposium on Ice Physics Held at Munich 9-14 September 1968), Len- ingrad, Gidrometeoizdat, 1973, 154 pages. S. Shumskiy, P. A., DINAMICHESKAYA GLYATSIOLOGIYA (Dynamic Glaciology), rioscow, Izd-vo AN SSSR, 1970, 200 pages. 6. Budd, W. F., THE DYNAMICS OF IC~ MASSES, issued by the Antarctic Division, De- partment of Supply, Melbourne, 1969, 216 pages. COPYRIGIiT: Arktictieskiy i antarkticheskiy nauchno-issledovatel'skiy institut (AANII), 1975 12 - FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2047102109: CIA-RDP82-00850R400504020048-2 FOR OF'FICIAL USE ONLY RADAR FM SIGN~?LS REFLECTED FF,OM ICE SURFACES AND POSSIBILITIES OF TIiEIR MODELING Leningrad TRUDY. ORDENA LENINA ARKTICHESKIY I ANTARKTTCHESKIY NAUCHNO-ISSLEDOVATEL'- SKIY INSTITUT. FIZICH~SKIYE METODY ISSLEDOVANIYA L'DA I SNEGA in Russian No 326, 1975 pp 17-20 [Article by A. B. Bahayev, V. P. Logachev, V. N. Parfen.t'yev, V. A. Fedorov and G. P. Shelomanova] [Text] This article gives some results of experimental investigations of ,the phys- ~ ical properties of ice surfaces and the radio signals reflected from them. Experi- mental investigations of the rangefinder signal were made with smooth and hummocky ice of different salinity with a thickness of about 2 m. In rangefindin~ it is important that saline sea ice at its lower edge has a trans- itional unconsolidated layer attenuating the reflection of the sounding signal. A source of radiosignal loss is also the unevenness of both edges of the ice layer. With a roughness parameter greater than 0.2 the periodicity of change in the mirror : reflection coefficient KfQ, characteristic of the layer, disappears and Kfp becomes a random value [1]. In the course of making the experiment, on the basis of the measurements computa- tions are made of the specific effective area of reflection for ice with different degrees of unevenness of the edges. The computations were made using the formula (IGr.)2 . //lslll ~~up ~1~ _ --~,,,-:~x2 : � e~r ~ ~'n ' _ where H is the range; ~ i.s the angle of surface irradiation; D is the antenna am- ~ plification factor; T is the radiation wavelength; Q~,~Y is the width of the antenna directional diagram in the orthogonal planes; Prec is the power received in the antenna; Pp is the radiated power. ~ Figure 1 shows the dependence of on the angle of irradiation of ice surfaces. The accuracy in measurements is (1.5-2.0 db). Using the proportional relationship r H are the spherical coordinates of the spatial position of elementary reflectors. Assuming the antenna diagrams to be axisymmetric and the reflecting medium to be isotropic with respect to azimuth the signal at the output of the ~ balanced mixer can be determined using the formula r~r~ F. (H, f/, t) cos ~4? (H, /f, t) ~_~~r (1~, ~f)~, (4) H !I ~ where H) is the equiprobable initizl random phase. After the necessary com- putations it is possible to obtain the time-averaged correlation function of this signal [1,2] [b = bal~ /lr~~~, ' N~~~/)'(H, /!)k~~~Ek~H, //)ct~s'?~ckF~~. ~5~ _ where ~ k( e, H) is dependc ,r ~n the type of modulating function; D2( e, II) is the dispersion of an elemen~ar~~ signal. The averaged energy spectrum of the signal of beats in this case is written in the form of the equation W Sr,~f. 1)-=J' ~~[)2(y, J' S(f - kF,~)Ek~f~, 1/). ~6~ H N A-I - In ttie case of a pencil-beam antenna the broadening of tlie spectrum will occur only due to the thickness of the reflecting layer. The factor D2( e, H) includes the nor- ma l izc~cl function f(~, II) characterizin~ the reflecting properties of the ice. In tlie c.ase of a pencil-heam antenna I(H. =IH(~~)~H:.~~�~,s~. c~) 15 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2047/02/09: CIA-RDP82-00850R400504020048-2 FOR OFFICiAL USE ONLY For ice with a low salinity and fres.h ice in the centimeter range the function fe (H), as demonstrated by the experiment, is apnroximated well by the expr~ssion IH(f~)===n,r,~ii -fi,~-~-a1s~~r--~~1~, c8~ where b(z) is a delta function; A1, A2 are coefficients dependent on the electro- physical parameters of the reflecting layer of ice. With expression (8) taken into account, the readings of the frequency rangefinder in the case of narrow antenna directional diagrams can be written in the form ~ F: a~I � r., � ii, ~ X , ~i--~H~ -1- ~Il,>' I F----�- - nl f?; ~9~ 4e//~~~,1/~~ E~_ X__._ ~ _ , _ where �ice is the mean value of the dielectric constant in the thickness of the ice; FM is the modulation frequency; ~ f is the frequency u~viation; c is the speed of light. - For practical computations a majo~ role is played by the values of the electrophys- ical parameters of ice in the SHF range. We used the results of ineasurement of � ice and tg S ice �btained by B. T. Kapitkin. All ttie experimental results and computations cited above indicate that rangefinder rI~ apparatus can be used with some modernization for determining the parameters of the icz layer, for example, its thickness Q Hice� A simplified block diagram of one - of the possible methods for processing the rangefinder signal for determining the thickness of the ice layer should contain an envelope detector and a unit for meas- uring the mean modulation of signal frequency, averaged for the period, at the out- put of the envelope detector. With expressions (6) and (8) taken into account, it can be shown that the mean mod- ulation of signal frequency, averaged �or the period, at the detector output in the case of a narrow antenna directional diagram is proportional to the ice thickness OHice� In conclusion we should note the following facts: 1. The results of experimental investigations of the reflecting properties oi ice ' surfaces make it possible to find new methods for obtaining information on the re- flecting surfaces. 2. It is fundamentally possible to determine the thickness of a thin ice layer on the basis of use of radio rangefinding FM apparatus. 16 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/42/09: CIA-RDP82-00850R000500020048-2 FOR OFFICIAL USE ONLY BIBLIOGRAPHY l. Zubkovich, S. G., STATISTICHESKIYE KHAR.AI~TERISTIKI RADIOSIGNALOV, OTRAZHENNYKH OT ZEMNOY POVERKHNOSTI (Statistical Characteristics of Radio Signals Reflect- ed From the Earth's Surface), Moscow, "Sovetskoye Radio," 1968, 223 pa~es. 2. Tsvetnov, V. V., "Statistical Properties of Radar Signals From Extended Surfaces in Systems ~dith Internal Coherence," TR. MAI (Transactions of the Moscow Avia- tion Institute), No 1, pp 5-26, 1966. ~ COPYRIGHT: Arkticheskiy i antarkticheskiy nauchno-issledovatel'skiy institut (AANII), 1975 ~ 17 _ FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 FOR OF'FI~IAL USE ONLY INFLUENCE OF ICE STRUCTURE ON ITS RADIATIOId CHARACTERISTICS IN THE SHF RA2dGE ~ Leningrad TRUDY. ORDENA LENINA ARKTICHESKIY I ANTARKTICHESKIY NAUCI~IO-ISSLEDOVATEL~- SKIY INSTITUT. FIZICHESRIYE ifETODY ISSI.EDO~IANIYA L'DA I SNEGA in Russian No 326, 1975 pp 21-23 [Article by A. Ye. Basharinov and A. A. Kurslcaya] [Text] Experimental investigations of radiothermal radiation of sea and continental ice carried out in the Soviet Union and the United States have revealed the spec- tral ~haracteristics associated with the nature of ice, its age, degree of salinity and microstructure [1-4]. In this article we describe the influence exerted on the SHF radiation characteristics of sea ice by the effects of scattering on air bubbles and small inhomogeneities. The microstructure of sea ice experiences changes dependent on the conditions of ice formation and age.~Young ice with a thickness of the layer of several deci- meters has increased moisture content and salinity. With an increase in ice age the moisture and salinity content decrease. In the upper layers of the perennial ice there is an increased content of air bubbles. j~ith a strong degree of pnrosity the air content increases to 100 cm3/kg. According to data from measurements made on the artificial earth satellit.e "Cosmos- 243" over the Antarctic zone, in the re~ion of perennial ice there is an apprec- iable decrease in radiobrightness temperature for the short-wave parts of the range. Figure 1 shows experimental data.for the spectral dependences of the degree of - blackness for young and perennial ice obtained in processing the results of observ- ations cited in [1, 4]. The transfer of radiation in the upper layers of perennial sea ice is accompanied by tlie ~ffects of scattering on inhor,?ogeneities of the diel- ectric constant. The emissivity of ice formations is determined by the value of the dielectric constant and the thickness of the ice layer [2]. The effect of the influence of internal scatterings, dependent on the relationship of the sizes of the inhomogeneities, wavelength and degree of ice porosity, is re- flected in the form of the spectrum of radiobri~htness temperatures and.on the angular characteristics of the radiation field. The degree of blackness of the emitting layer of ice, with internal scatterin~s taken into account, is evatuated using the expression ~ x t - ~R.-I-~~ (i R,)I, (1) is FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2047/02/09: CIA-RDP82-00850R400504020048-2 FOR OFF'ICIAL USE ONLY tahere R� is the reflection coefficient at the boundary of the ice layer, determin- ed witliout allowance for internal scatterings;f~a is a coefficient characterizing tne fraction of the power scattered on inhomogeneities; ~ice~l - R~) is a coef- - ficient characterizing the fraction of the power scattered in the upper half-space. x 1 ~~-~----------------o i o~e / . ~ o,e ~ . ~ o,-~ 2 0 3 � I L t_ ~ ~ 3 5 7 ~,cr Fig. 1. C~~.puted and experinental spectral dependences of degree of blackness for "younb" and "old" ice obtained in processing the resul.*_s of observations on tlie "Cosmos-243" artificial earth satellite and from "Convair-990." [Jith allowance for the effects of single scattering frora randomly distributed small inhomogeneities the mean value of the coefficient of reflection from an elementary volume is determined by summation of the partial scattering fields p, -=},�f== ~y-Q , ~2) where O'i is the scatterinR section of the inhomogeneities; dN/dV is the spatial clensity of tl~e inhon ~~;en Lties. T'he mean va:lue of the refi~~.cion coefficient from a layer with a depth correspond- to ttie ~.kin layer is determined usin~ the formula ,~~r ~IV~-o ~a.~~ya~ [ ~ = elem(ent,~ry) ] wliere ~ elema -~~2'~ ~ tK b is the depth of the skin layer. is the depth of the skin layer. The spectral dependence of tlie scattering section, determined by the relationship of the sizes of the ir~homogeneities and the wavelen~th, is manifested in the form of ~ decrease in the degree of blackriess with a short2nin;; of the ~vavelength. Model computations of the spectral depe.ldence of the degree of blackness of the ice cover were carrieci out taking into account the contribution of the effects of scat- tering on bubble inhomogeneities of spherical form on the assumption of a 19 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2047/02/09: CIA-RDP82-00850R400504020048-2 - FOR OFFICIAL USE ONLY unifornity of the structure of the upper layer to a depth of 30--60 cn. A co~parison of the computed and experinental values: of the spectrum of the degree of blackness _ for long-term sea ice makes it possible to evaluate tlie degree of porosity of ice samples (see Fig. lj. Thus, an evaluation of the content of air inclusions for the _ sounded ice fields ~ives 30-~0 cm3/kg with a mean diameter of the bubbles of about 1 mm. The difference in the SHF spectral characteristics of one-year and perennial ice can be used in the diagnosi~ of sea ice. . B.IBLIOGRAPHY - 1. Basharinov, A. Ye., Gurvich, A. S., Yegorov, S. 'i'., Zhukov, V. I. and Kurskaya, - A. A., "Results of Observation of Thermal Radio Emission of the Earth's Surface According to Data of the Experiment on the AES 'Cosmos-243'," KOSPiICHESKIYE ISSLEDOVANIYA (Space Research), Vol IX, No 2, pp 268-279, 1971. 2. Tuchkov, L. T. , YESTESTVEtdNYYE SHUPiOVYYE tZLUCHEtdIYA V RADIOKANALAI:H (Ptatural Noise Radiations in Radio Channels), Moscow, "Sovetskoye Radio," 1968, 152 pages. 3. Tuchkov, L. T., Basharinov, A. Ye., Kolosov, ti. A. and Kurskaya, A. A., "Ther- mal Radio Emission of the Ice Cover in the SHF Range," TRUDY GGO (Transactions of the Main Geophysical Observatory), 210 222, pp 159-161, 1968. 4. Wilheit, T., Nordberg, id., Blinn, J., et al., "Aircraft Measurements of Micro- wave Emission From Arctic Sea Ice," RF.~10TE SENSING OF ENVIRONMEIIT, No 2, pp 25-28, 1972. COPYRIGHT: Arkticheskiy i antarkticheskiy nauchno-issledovatel'skiy institut (AANII), 1975 20 FOR OFFiC[AL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 FOR OFFIC[AL USE ONLY REMOTE MEASUREMEt1T OF SEA ICE THICI:NESS BY RADAR METHODS Leningrad TAUDY. ORDENA LEtlIt1A ARKTICHES~IY I ANTARI:TICIIESI:IY NAUCfII10-ISSLEDOVATEL'- SICIY INSTITUT. FIZICHESI:IYE 2iETODY ISSLEDOVANIYA L'DA I SNEGA in Russian No 326, 1975 pp 51-54 [Article by M. I. Finkel'shteyn, V. A. Kntev, V. G. Glushnev and E. I. LazarevJ [Text] Introduction. The radar method, based on measurement of the time interval between separately observed signals reflected from ttie ice boundaries, is widely used in measurin~ the thickness of glaciers, for example, in Antarctlca [1J. Due to the successes of nanosecond pulsed apparatus and the technique for the process- ing of signals the method can be applied to thinner sea ice whose thickness usual- ly does not exceed 2 m. However, a great attenuation occurs in this case. In order to compute the ratio of the amplitudes of signals reflected from the boun- daries of sea ice it is possible to use the data of J. Addison [7], which are con- firmed by our radar sounding of sea ice. There is a definite "frequency window" lying in the meter and partially in the short-wave wavelength ranges [6]. Method of Individual Radio Pulses A radio pulse is characterized by the presence of at least several, for example, three periods of high-frequency oscillations, so that the minimum activity is ti umin - 3/f, where f is the frequency of higl-~-frequency oscillations. This cor- . - responds to the minimur.? thickness of the homogeneous layer of ice hicei,lin - �ice~u in~2~ wtler~ vice P~eJ ~ ice is the velocity of radio wave propagation in ice ice is the compl~:ti dielectric constant). _ Table 1 gives the limiting hicemin values and the ratio r of the bottom/'top ampli- tudes [2]. The salinity of ice was selected so as to be characteristic for sea ice of the corr~spondin~ thic~cness (ice temperature -30�C). The table shows that of the three frequencies only for f= 40 MHz is the ratio of tile bottom/top acceptable for measurement from tlie point of view of resolution of sj.gnals *aith a limited ice tliickness. However, in this case hicemin = 5.9 m. Witti hi~her 'rrequencies the bottom/top ratio ~ 0.1, whiclt makes the process of ineasurement of the time interval between two reflected pulses, being at che limit of resolution, virtually impossible. Only a frequency f= 300 MHz makes a resolution of 0.8 m acceptable for practical purposes, but in order to 21 FOIt OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2407/02/09: CIA-RDP82-00850R000500420048-2 FOR OFFICIAL USE dNLY ensure measurements there must be an increase in the r ratio by two orders of ma~nitude, for which the salinity of ice must be approximately tr.ree times less. Table 1 Dependence of Itesolution and hicemin Value on Frequency of Sounding Signal f~ NIIiz ~umin+ nanosec S, % 11icemin' m r - 40 75 1-1.5 5.9 0.38 100 30 5-6 2 0.1 300 10 12-13 0.8 J.03 = Method for Shock Excitation of Antenna ~ , In 1960 J. Cook proposed the use of a monopulse in the form of one period of a hi~h-frequency oscillation for ensuring the contradictory requirements of use of the above-r~entioned frequency window and maintenance of the necessary resolution [8]. The shock excitation of an antenna was proposed in order to obtain a mono- pulse. It should be noted that the optimum shape of a pulse from the point of view of the best resolution in the case of shock excitation differs from a Mono= pulse j3). This method was cr.ecked by M. Meyer, using horn antennas having a frequency band from 150 MHz to 600 MHz [10]. In our experiments (in 1969 from a beacon ann in 197~J from aboard a helicopter) the shock excitation method was used by us in atp, paratus for the shaping of short radio pulses. Using wind-band vibrator it was possible to obtain radio pu~ses with a duration of 6, 1Z, 20 nanosecond5 corresponding to the central frequencies 440, 300, 140 MHz. In addition, using more low-frequency antennas with a central frequency of.70 MHz it was possible to oUtain pulses with a duration of 40 nanoseconds. In addition to measurement of ice thickness, the inverse problem was solved: determination of.the~ice parameters - from the ratio of the amplitudes of the signals and the time interval between _ them [4]. These experiments confirmed the possibiltty of using the method for fresh-water and slightly saline ice and its inapplicability for highly saline sea ice. This - is associated with a 5tr.oil~ nonuniformity of the frequency characteristic of real antennas, especially in the low-frequency region, which leads to the "ringing" phenomenon. This was mentioned by S. Evans as an important technical problem [9]. Videoimpulse P4ethod (Method of Shock Excitation ~Jith Correction) We proposed and from aboard a helicopter (1971) and aircraft (1972, "973) made practical use of a method for the compensation of ringing based on the use in the receiving channel of narrow-band channels for the multiple frequencies F, 2F,..., - nF, which jointly with the frequency characteristic of the antenna form a uniform comblike filter [5]. The signal with which a particular comblike f ilter is matched is a packet of video pulses with the repetition rate F. Measurements can be made from one of the pulses in the packet. 22 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 FOR O~F1C[AL USE ONLY h n~cM hice a ~ = s,u5 v ~ ~ice\ ~ f 150 - - 0 100 � � ~ C c2,30 . v~ 50 � i ~ 0 2 ~ j~ 3 e t Hc � io - so ' nanosec Fig. l. Dependence of true thickness of ice hice on time interval between pulse maxima ~ t. 1) Sice -~�5-13�/00, t~,ater --22 --36�C; 2) 1.5-2.5�/00, twater --8- -18�C; 3) perennial ice. Our experiments revealed the possibility of ineasuring the thickness of sea ice be- - ginning ~aith 50-60 cm. The presence of an adequate stability of the mean velocity of radio wave propagation in ice of different thickness was demonstrated for sev- eral gradations of the state of ice (Fig. 1). For one-year sea ice at an air tem- perature tair -20�C and a mean ice salinity S= 4.5-13�/0o the velocity of radio wave propagation in the ice is 2.3 times less than in the air. ~dith a decrease in salinity this ratio decreases to 2 or more to the known value 1.79 for fresh ice. An increase in air temperature tair above -20�C exerts a considerable influence on the attenuation of radio waves in ice. In this case for young highly saline ice and Per.ennir:il ice tl~e s'~nal do~ s not attain the lower layers, which makes it difficult to deterr~ine the velocity o' radio waves in the ice and also calibrs*_ion when meas- uring ~he thickness of such ice. B I BI.IOGRAPHY 1. (3ogorodskiy, V. V. , FIZICHESKIYE METODY ISSLEDOVANIYA I~~DPIIKOV (Pliysical Melh- ods for Investigating Glaciers), Leningrad, Gidrometeoizdat, pp 3-211, 1968. 2. Mendel'son, V. L., Kozlov, A. I. and Finkel'shteyn, i4. I., "Investigation of Some Electrodynai~iic Models of Ice in Radar Sour.ding Problems," IZV. AN SSSR: _ I~i7.IKA ATMOSr~RY I OI~EANA, Vol VIII, No 4, pp 396-402, 1972. 3. Finkel'shteyn, M. I., "Optimum Shape of Pulse in Radar Sounding of Sea Ice," IZADIOTEI:I~NIKA I ELEKTRONIKA (Radio Engineering and Electronics), Vol 25, XV, No 7.2, pp 2468-2472, 1970. 23 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 FOR OFFICIAL USE ONLY 4. Finkel'shteyn, M. I.and Glushnev, V. G., "Some Electrophysical Characteris- tics of Sea Ice r4easured by Radar Sounding in the Meter 6davelength Range," - DOKLADY AN SSSR (Reports of the USSR Academy of Sciences), Vol 2G3, No 3, - pp 577-580, 1972. - 5. Finkel'shteyn, PS. I. and Kutev, V. A., "Sounding of Sea Ice Using a Series of Videopulses," RADIOTEKHNIKA I ELEKTROPdIICA, Vol XVII, t1o 10, pp 2107-2112, 1972. 6. Finkel'shteyn, M. I., Kozlov, A. I. and Mendel'son, V. L., "Modeling of Reflec- tion of Radio ~daves From Sea Ice," RADIOTEKHNIY.A I ELEKTRONIKA, Vol XV, No - 11, pp 2282-2288, 1970. 7. Add:tson, J. R., "Electrical Properties of Saline Ice," J. OF APPLIED PHYS., Vol 40, No 8, pp 3105-3114, 1969. 8. Cook, J. C., "Proposed Monocycle Pulse Very-High-Frequency Radar for Airborne Ice and Snow Measurement," TRANS. AMER. TEE. P 1(Commun. and Electronics), Vol 79, Pdo 51, p 588, 1960. 9. Evans, S., "Progress P.eport on Radio Echo Sounding," THE POLAR RECORD, Vol 13, No 8S, pp 413-420, 1966. 10. Meyer, M. A., "Remote Sensing of Ice and Snow Thickness," PROC. OF TH~ FOURTH SYMPOSIUM OF REMOTE SENSING OF ENVIROP~MEtdT, The University of Michigan, pp 183- 192, 1966. . COPYR~IGHT: Arkticheskiy i antarl:ticheskiy nauchno-issledovatel'skiy institut (AANII), 1975 ~ 24 - FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2407/02/09: CIA-RDP82-00850R000500420048-2 FOR OFFICIAL USE ONLY INSTRUMENTATION FOR INVESTIGATING SPECTRAL REFLECTION OF LIQUID WATER IN THE - IdAVELENGTH REGION 1-50~-m Leningrad TRUDY. ORDENA LENINA ARKTICHESKIY I ANTARKTICHESKIY NAUCHNO-ISSLEDOVATEL~- - SKIY INSTITUT. FIZICHESKIYE METODY ISSLEDOVANIYA L'DA I SNEGA in Russian No 326, 1975 pp 74-79 [Article by M. A.. Kropotkin] ~ [Text] Remote sensing methods, bas'ed on use of radiations in the IR ra.nge, are now being used more and more extensively in measuring the temperature of a water surface. In interpreting the results obtained by remote sensing methods it is necessary to know such optical characteristics of the water surface as the coef- ficients of spectral reflection, spectral and integral radiation in the visible , ~ and especially in the IR part of the spectrum, and also the dependence of the optical parameters of water on such factors as salinity and temperature. Investigations for study of the reflection of liquid water in the IR range have al- ready been carried out over the course of several decades. During recent years the reflection properties of liquid water are being investigated especially intensive- - ly. Work on investigation of the reflective properties of liquid water has also been carried out at the Department of Principles of Electrovacuum Technology at the Leningrad Electror_echnical Institute. In this article we describe instrumentation used at the Leningrad Electrotechnical Institute for. measuring the spectral coefficients of reflection of liquid water - in the wavelength r.~.~ge fro~ 1 to 50~,~.m [2, 3] and give some results of the inves- _ tigations made. The study of the spectral reflection of liquid water is complicated by the .f.act ehar, first of all, the coefficients of reflection of liquid water, especially 3.n the case of. small angles of incidence, in the IR range are small, and second, the surface of the liquid water does not re:.;ain plane due to vibrations of the ~;round. Accordingly, sometimes re�lection at the air-liquid water discontinuity is not i.nvestigated, but instead at a dielectric-water discontinuity. The coef- Licients of reflection of the latter are then determined by computations. In ex- perimental respects Guch a method is very convenient, but due to the absence of materials transparent Ln the IR region and insoluble in water, such a method can be ~lsed only in the region of cvavelengths less than 12-15f,~,m. At the Leningrad Electrotechnical Institute the investigation of the spectral re- flection of liquid water has been accomplished using instrumentation in which a ~r~irror hemisphere is used for focusing the radiation reflected by the water. 25 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 FOR OFFICIAL USE ONLY bue to the use of this hemisphere there is a considerable reduction in the harmful influence of ground vibration. In the wavelength region up to 20f,,t.m the measurements were made with an attachment to a standard single-ray IR spectrometer, whose optical diagram is shown as Fig. 1. In this attachment the cell with the water to be investigated and the radiation detector are situated under the mirror hemisphere at an identical distance from - the center of the hemisphere in the plane of its great circle. The plane mirror , M4 can be rotated. When making measurements of reflected radiation this mirror directs monochromatic radiation onto the water surface to be investigated. The reflected radiation is focused by the mirror hemisphere onto a radiation detector. ~Jhen measuring the incident radiation the mirror MCF is turned into a second posi- tion, in which it direc~s the radiation directly onto the detector. Thus, if the reflection coefficient of the mirror surfacing of the hemisphere is known, by means of this attachment it is possible to measure the absolute reflection coef- ficient of water. The reflection coefficient of the mir.r.or surfacing of the hemisphere was deter~,ined with an accuracy to tl% by measuring the reflection coefficient of a plane mirror ~~hich was sprayed simultaneously with the hemisphere. The possibility of ineasuring the absolute reflection coefficient is an important advantage of this measurement method since in the measurement of the relative reflection coefficient it is neces- sary to use a`c~mparison mirror. In this procedure it is necessary to take into ac- count the difference in the character of the polarization of the radiation re- ~ flected by the water and comparison cnirror, especially with angles of incidence close to the Brewster angle. As the radiation detector use was made of a radiation thermoelement with a window - RRS = 5. In measurements in the wavelength region up ta lON.m the recording in- strument was an M 195/2 multilimit galvanometer, in parallel with which a 1.7- l:ilohm resistor was connected. The response of the measuremer~t system could there- fore be varied: it was maximum when measuring reflected energy and 10 times less when measuring incident energy. With measurements in the wavelength region 12-20 �.m, where tt~e source energy is small, the galvanometer was replaced by a d-c affi- plifier and an EPP-09 automatic recorder. _ In the wavelength zone from 20 to 50~..m the measurement of spectral reflection of ~ liquid water was accomplished using an apparatus consisting of a~ong-wave single- ray IR spectrometer designed using a Pfund autocollimation scheme in which the dispersing element used was interchangeable diffraction gr.atings and an optical system focusing the monochromatic radiation either on the sample or on the detec- tor. The optical system and the diffraction gratings are situated under the mirror hemisphere. The switching of the ray from the sample to the detector is accomplish- ed using the rotatable spherical mirror. . The source in this apparatus is a globar (lamp); the detector is a radiation ther- moelement with a KRS-5 window operatin~ in combination with a d-c amplifier and an - EPP-09 electronic automatic recorder. In order to suppress the scattered short-wave radiation the optical system of the monochromator has two fluorite reflecting fil- ters and a transmission filter of smoked polyethylene. In addition, in the measure- m.ents use wa.~s made of a cutting slide of sodium fluoride. All the enumerated 26 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/42/09: CIA-RDP82-00850R000500020048-2 FOR OFFICIAL USE ONLY mecisures nkide it possible to reduce tlie level of scattered interfering shoxt-wave - radiation to 1-2%. ~ e 3~ M2 M4 3n u 33 I 3"` M3 _ Mh i 3 i Ml - -p pTj ~ti i r~ S o' Fig. 1. Optical diagram of attachment. He~. ~ o,oe. z i�~.1 `..d s o,os~ i 3 (1,04 % rl �~1~ �r~ ' . O,U2- . � � O - - - - -----r- ------r------ ---r-------r---~~wnr ~IIl 10 2Q 30 40 Fi~. 2. Reflection spectrum of liquid water. - T)uring the mr~asurements the water was poured into a special cell which was divided into a ntunber of sections by several horizontal and vertical partitions. The water ].m tlie ~trait. The prof iles of the velocity of the tangential component of drift 37 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 _ FOR OFFICIAL USE ONLY across the central part of the strait and between the zone of compression and the shore of the mainland to all practical purposes are similar to one another. It ia known from observations that the shore exerts a different influence on the _ normal and tangential drift components. However, traditional methods for the study of ice drift under real conditions~(radio beacons, DARi4S stations, drifting sta- tions) have not given simultaneous data for a detailed spatial analysis of change of these components. Surveys made using the side-looking radar make it possible to carry out such an analysis. Figure 1 shows the change in ice drift velocity components for ice with a continuity of 9-10 units. The surveys were made in winter. In this case at a distance of 130- 140 km from the land, where the drift components for all practical purposes no longer chan~ed, the general direction of ice movemetit was at an angle 23� to - the boundary of the shore ice (the width of the shore ice was about Z5 km). It follows from tlie cited data that with approach to the shore the tangential com- - ponent vp first increases, whereas the vn component decreases. This is attributable to the fac~ that in this sector the value of the drift velocity vectors virtually _ does not change. At the same time, they rotate and in direction they gradually approach the direction of the shore ice bound3ry. - At a distance of 40-45 km from the fixed ice the influence of boundary zone friction begins to be reflected. Within its limits the v~ values intensively decrease and at - the boundary of the shore ice this component is only 0.4 of its maximum value. The normal drift component vn within the lj.mits of the boundary zone is usually less than the v~ component. In the immediate neighborhood of the shore or shore ice in a zone with a width of 10-15 km it is close to zero. Beyond the limits of the boundary zone the relationship between the v~ and vn values can be different and be determin- ed completely by the value of the ~ angle. = In summer the change in the ice drift components in general is characterized by the - same regularities. This is indicated by the data obtained in the neighborhood of the islands. However, the width of the boundary zone in the presence of packed ice during this period decreases to 10-15 km. The reaction of the normal~drift compon- - ent to the influence of the shore is transmitted within the region of the ice cover the same, evidently, as over shorter distances. At this time ~ve have not been able to obtain any specific data on this problem. The drift of the ice cover is accompanied by relutive movements of the floes. The _ intensity of movement of the floes relative to one another has already been invest- igated on the basis of an aerial photographic survey with averaging of velocity dur- ing time intervals of about one hour [2, 4]. Using films from the photorecording unit we analyzed the velocities of relative movement of the ice with time averaging of two days. The mobility of the floes was examined in the direction of the mean drift and along the normal to it. For this we used the mean square values of the longitudinal v'~ and transverse v'n deviations of the velocity vector of each floe from the vector of inean ice drift velocity. The areas of the zones for which the cirift was averaged were 600-800 km2. It follows from these results that the 38 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2047/02/09: CIA-RDP82-00850R400504020048-2 FOR OFFICIAL USF.. ONLY relative displacements of the floes along the general drift increase with an in- crease in the mean ~~alocity modulus v for movement of the ice cover (Table 3). Table 3 Nean Square Values of Longitudinal Deviations v'~ of Ice Drift Velocity Vector, in km/day Ice continuity, Mean ice drift velocity, km/day ~ units . 7-9 9-11 11-13 13-15 15-17 4-6 1.81 2.43 2.69 2.98 3.56 7 1.20 1.55 1072 2.06 2.35 8-7_0 0.62 0.74 0.86 1.11 1.30 Tiie dependence of the v'~ value on'the v and C parameters is entirely satisfactor- il.y aporoximated b;~ the expression v,=(U,41 -O,U37C)v. The mean square values of t'ne transverse displacements of floes v'n also increase witli an acceleration of tlie gen~ral movement of the ice cover (Table 4). At the same time it is impossible to note any significant influence of ice continuit~ witti its chan~e from 4 to 9-10 units. In general, ttie deviations v'n are comparable with the longitudinal deviations of the drift velocity vectors for packed ice. ' The mean deviation bet~veen v'n and v is 0.102. It should be noted that in a coastal zone with a width of 15-20 km the fluctuations of the drift velocity vector are ~reater than in the nore seacaard zone. For ex- ample, with an ice continuity of 4-6 units the longitudinal deviations exceed the v~lues cited in Table 2 on the average by a factor of 1.5. Tlie values of the trans- verse deviations near ttie shore j.ncrease by a factor of 2-3. Table 4 Mean Square Values of Transverse Deviations v'n of Ice Drift Velucity Vector, lcm/day v, km/day v` km/day v, km/day v'n, km/day ~_g p,7g 13-15 1.21 9-11 1.13 15-17 1.73 L1-13 1.10 17-19 1.95 A joint analysis of the deviations v'~ and v'n makes it possible to establish a change in the nature of the distribution of the velocity vectors for movement of floes rela- - tive to the mean vector with an increase in continuity of the ice cover. It was found ~ tt~at in open pack ice the longitudinal displacements of the floes predominate over the transverse displacements, that is, v'n/v'~ ~ 1(Fig. 2). [dith an ice continuity of. about 8 units ttle deviations on the average become equal. In more continuous ice tlie transverse displacements of the floes are greater than the iongitudinal dis- placements. The dependence of the ratio v'n/v'Q on ice continuity is determined ap- proximately using the formula � ~ v,~ 1 1~~ ~l,0'l 0.;~5;i(; . 39 FOR OFFICIAL USE ONL'~' APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/42/09: CIA-RDP82-00850R000500020048-2 M'OR UM'M1(;IAL US~: UNLY v nlv'I ~A~ � i,e i,e - . ~ . ~,s � i,o . o,e u,a ~ � u,~ � ~ - o,z units u T -T ~ C~6an 2 ~ 5--9 7 8~ 10 ' Fig. 2. Change in ratio vn'/v~' as function of ice continuity (in units). Interesting results were obtained in an analysis of the position of the axes of the ellipses of scattering of the deviations v~ and v'n. If the resultant drift is di- rected in the direction of any obstacle (toward the shore or zone of stranded ice), limiting the movements of the ice cover, the longer axis of the ellipse of scatter- ing rotates relative to the mean velocity vector, tending to be oriented along the general direction of the obstacle. The very same occurs in the case of drift of open pack ice in the direction of the ice mass. For example, with a direction of the mean velocity vector at an angle of 50� to the boundary of the ice mass the greater axis of the e~lipse was deflected from this boundary by only 15�, that is, it was turned relative to the mean drift by 35�. In the ice mass itself, near its boundary, with a similar direction of the resultant movement of the ice, the el- lipses of scattering were also oriented along the boundary of the pack ice. - It was established earlier on the basis ~f materials from an aerial photographic survey that with the drift of apen pack ice, uniformly distributed in space, and in the absence of obstacles the greater axis of the ellipses is usually deflected from - the direction of the averaged drift by not more than .10� [4]. Now it has been found ~hat in the presence of an ice continuity gradient the displacement of the floes relative to the mean velocity vector occurs differently. The velocity vectors are distributed in such a way that there is a predominance of drift fluctuations in the region of lesser ice continuity. Evidently, this peculiarity is attributable to internal processes transpiring in the ice cover as a result of both contact and hydrodynamic interaction of ice [6]. On the basis of materials from a radar survey it is possible to investigate the spa- tial variability of the field of ice drift velocity. As a characteristic of the correlation between the velocities of ice movement at individual points in the drift field we computed the normalized spatial correlation functions: 40 ~ FOR OFF[CIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2047/02/09: CIA-RDP82-00850R400504020048-2 FOR OFFICIAL USE ONLY - . i _ ~ }J v' (~J v' ~ n l i = i k - a~: ~ where v'(L.) and v'(L�+ are the deviations from the mean drift velocity at the i i points Li and Li ,Q is the interval in which the correlation function was de- termined; ~ v is the dispersion of drift velocity. In computations we used a scheme of ice drift taking in an area of about 110,000 km2 and averaged during a time interval of two days. The analysis was made in the direction of the general drift and along the normal to it. The values of the mean velocity of ice movement and the standard deviations along ~he general drift were equal to v= 9.2 lcm/day; = 0.02 km/day, and along the normal to the drift v= 9.4 km/day; U'~ = 2.90 km/day. R i,~~ , o,e i o.s \ _ _ ? \ 0,4 \ i ~ ~ O.Z ~ / \ ~ 8 I \ ---~-I ~ N M U ~q 10 12 I4 18 02 \ / \ ~ ~ 0,4 Fig. 3. Normalized spatial correlatior, functions of drift velocity of pack ice. 1) along direction of general drift; 2) along normal to general drift. It can be seen froM Fig. 3, which shows the results of computations, that the dif- ference in the normatized correlation functions in the directions mentioned above is extremely sig~lifi,:ant. A~ubstantial linear correlation between the drift velo- cities across the movement o.. ice (with R(,~) < 0.5) is observed at points distant ~ from one anottier by not more than 18 km, whereas along the drift this distance in- - creases to 39 k.r.~. The first intersection of the axis of distances with ttie curve oC ttie correlation function along the normal to the drift is observed with = 35 km. 'Phe correlation function along the direction of drift attains zero with Q= 75 km. Thus, the mean values of the maximum size of the structural formations of the field of drift velocity in the direction of ice movement and along the normal to it differ by a factor of appr~ximately 2. This means that the structural forma- tions of drift velocity, that is, zones of increased and decreased velocities of ice movement, tiave an el].iptical shape and are drawn out in the direction of the ;.;eneral. movement of _~ce. One of the peculiarities of ice drift is rotation of floes during their translation- al movement. The floes can rotate both as a result of random interactions between them and under the influence of the general nonuniformity of the field of velocity 41 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 FOR OFFICIAL USE ONLY of ice movement. It is evident that the rotation of large ice fields for the most part is attributable to the nonuniformity of drift and to a lesser degrEe is de- pendent on random factors. For a clarification of this circumstance we analyzed tt~e rotation of 65 ice fields measuring from 2 to 8 km with an ice continuity of ;-10 units, making use of electronic photoregistry films. The velocity of rotation of the floes was compared with the local transverse drift velocity gradient in the sector of movement of each field. It was discovered that there is a direct correla- tion between these values, tliat is, with an increase in the absolute value of the transverse drift gradient the intensity of rotation of floes also increases. This ~lependence is expressed approximately by the equation do , u~ - i)~1 where the transverse drift velocity gradient a ~~a n is expressed in km/day / km, and the velocity of rotation c,J in degrees per day. A study of deformation of the ice surface is of great importance, that is, an inves- tigation of the compressions and dilatations arising in it. For a quantitative evaluation of these phenomena we used the change in area Q S of a"surface ele- ment," discriminated from the characteristic points on individual floes. Since the electronic photoregistry films make it possible to establish the relative position of the floes at the times of the f3rst and second surveys, it is also possible to determine the deformation L~ S of the contour during the interval between observa- tions Q t. The intensity of deformation is expressed most simply by the relative change in the area of a surface ~~~ment in a unit time - S2 - S~ ~L- : S1 Q~ ~ where Sl and S2 are the areas of the contour during the first and second surveys. The relative deformation value is identical to the divergence of the ice drift velo- city field, A total of 134 E.~-values were obtained by the described method using data from summer surveys of pack ice. Seventy of these were with a plus sign and 64 were with a minus. In the camputations for the most part we discriminated rectangular contours. The areas of the figures on the average were 100-120 km2. It was established as a result of a careful analysis of the materia"ls that the deformation of figure~ of such a scale is determined by the changes of both the velocity and direction of drift. The mean positive ~,l value was +0.142; the mean negative value was -0.136; the mean for the entire sample was +0.009; the standard deviation was 0.186. The extreme ~.t,values were +0.95 and -0.38. The curve of~,t distribution is characterized by a positive asymmetry and a positive excess. The totality of these data makes it pos- sible to assume that in the studied situation the deformations of the surface of _ the continuous ice cover during compression were manifested less intensively than during dilatation. Spatially the � values were not distributed unsystematically, but form individual zones with positive and negative values. In such zones during the period between surveys there were dilatations or compressions of the ice respectively. The zones of compression, elongated along the normal to the general drift, alternate with 42 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2047/02/09: CIA-RDP82-00850R400504020048-2 FOR OFFICIAL USE ONLY zones of dilatation. The width of the first on the average is 30 km; the width of the second on the average is 40 km, The maximum negative~.t values were observed on the drift side of the islands, that is, in zones of intensive decrease in the velocity of ice movement. The maximum positive � values were o'oserved at the en- trances to straits, where, on the other hand, the velocity increases were consid- erable. In zones of positive � values it was usually possible to observe the form- ing of channels or chains of leads. In this article we have by no means examined all the aspects of use of side-looking radar for study of the dynamics of the ice cover in the coastal regions of arctic seas. Nevertheless, we hope that the results cited here will be indicative of the possibilities of a multisided application of this method, which is not dependent , on such factors as the illumination of the underlying surface and visibility. At the same time, we assume that the method requires further development, which evi- dently must be directed both along the lines of technical improvement of the radar system and along the lines of broad automation of the procedures of processing and analysis of the collected data. BIBLIOGRAPHY 1. Gorbunov, Yu. A. and Losev, S. M., "Use of the Side-Looking ~Toros' Radar Set for Investigating Ice Drift," TRUDY AANII (Transactions of the Arctic and Ant- arctic Scientific Research Institute), Vol 316, pp 153-162, 1974. 2. Gorbunov, Yu. A. and Timokhov, L. A., "Invastigation of the Dynamics of Ice," IZV. AN SSSR: SERIYA FIZIKA ATMOSFERY I OKEANA (News of the USSR Academy of _ Sciences: Physics of the Atmosphere and Ocean), Vol 4, No 10, pp 1086-1091, 1968. 3. Glushkov, V., et al., "New Means for Obtaining Ice Information," MORSKOY FLOT (Navy), No 9, pp 27-28, 1970. 4. I.osev, S. M., "Stati_stical An~lysis of Relative Mobility of Ice Cover," TRUDY AAi1II, Vol 307, pp 28-40, 1973. 5. Loshchilov, V. S, ana Voy~vodin, V. A., "Determination of Ice Cover Drift Ele- ments and Moveme~ts oi th~ Ice Edge Using the 'Toros' Airborne Side-Looking Radar Set," i'RGBLEMS AR'.~'?KI I ANTARKTIKI (Problems of the Arctic and Antarc- tic), No 40, pp 23-~~, ~a72. 6. Timokiiov, L. A., "Dynamics of the Ice Cover and Changes in Its Continuity," TRUDY AANII, Vol 257, pp 125-134, 1967. 7. Johnson, .J. D. and Farmer, L. D., "Use of Side-Looking Airborne Radar for Sea Ice Identification," J. CEOPIiYS. RES., Vol 76, No 9, pp 2138-2155, 1971. COPYRIGtIT: Arkticheskiy i antarkticheskiy nauchno-issledovatel'skiy ir.stitut (At1NII), 1.975 43 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2047/02/09: CIA-RDP82-00850R400504020048-2 FOR OFFICIAL USE ONLY OBSERVATIONS OF SEA SURFACE TEi~~ERATURE USING A RADIATIOII THERM(7METER FROM AN ICE RECODIIZAISSA:JCE AIRCRAFT ~ Leningrad TRUDY. ORDENA LENINA ARKTICHESKIY I AidTARKTICHESKIY NAUCIiNO-ISSLEDOVATEL'- SKIY INSTITUT. FIZICHESKIYE PiETODY ISSLEDOVANIYA L'DA I SNEGA in Russian No 326, 1975 pp 114-120 jArticle by A. I. Parar~onov, Yu. A. Gorbunov and S. M. Losev] [Text] During August-September 1973 in the eastern re~ion of the Arctic for the first time specialists made regular observations of the temperature of the sea surface using a radiation thermometer. The following problems were solved: deter- mination of the possibility of ineasuring the temperature of the sea surface in leads amidst thin and scattered ice, the collection of data on the temperature of the surface of ice of different a~e, evaluation of the accuracy of observations, perfection of the method for aerial temp~rature surveys from an ice reconnaissance aircraft. i'he following apparatus was used in carrying out surveys Precise Radiation Thermometer, Model PRT-5, Barnes Engineering Co., United States Range of ineasured temperatures, �C -20 - +75 Accuracy, �C 0.5 - Response, �C 0.1 Inertia, sec 0.5 Working range af ambient temperatures, �C -20 -+40 Working range of wavelengths, N.m 8-14 - An~le of view, degrees 2 ~lectronic Automatic Recording Potentiometer, Model KSP-4, USSR Range of ineasured voltages, mV 0-10 Rate of run of carria~e along entire scale, sec. 2.5 Input resistance, ohms 1000 Rate of motion of registry tape, mm/hour 20, 6Q, 240, 720, 1800, 5400 and same values x 10 Accuracy, % of entire scale 0.5 44 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2407/02/09: CIA-RDP82-00850R000500420048-2 FOR OFF[CIAL USE ONLY - Electronic Auromatically Recording Potentiometer (Ankersmit), Model SP-65V, Riken Denshi Co., Japan) Range of ineasured voltages 0-5 mV, 0-10 mV to 10 V on fixed and variable scales - Ra.te of run of carriage along entire scale, - sec 1.0 Accuracy, % of entire scale 0.5 Rate of motion of registry tape, ~/hour 75, 150, 300 _ mm/min 10, 15, 30, 60, 120, 240, 480 ~ Converter of voltage from 27 V d-c current to 220 V 50 Hz a-c current, voltage canverter type PO-300, po~aer 600-700 jd Model of IR Thermometer Developed in REVT Laboratory at Leningrad Electrotechnical Institute imeni V. I. U1'yanov (Lenin) in Portable Variant Range of ineasured temperatures, �C -SO - +100 - Accuracy, �C 0.5 Response, �C ~�2 Inertia, sec 2�~ ~Jorking range of ambient temperatures, �C -50 - ~-50 [7orking range of wavelengths,~,l,m 2.5-40 Angle of view, degrees 5.0 The checking of the working state of the apparatus was accomplished in the Radio- physical Research Section of the Arctic and Antarctic Scientific Research Institute _ in Leningrad and at the observatory of the Pevek Administration of the Hydrometeor- ological Service in Pevek. In carrying out the observations the apparatus was in- stalled aboard an I1-14 aircraft which carried out ice reconnaissance in the east- ern region of the Arctic. Methodological studies for checking the accuracy of tem- perature measurements were carried out during the time of flights for ice recon- naissance and temperature surveys during the period 14 Au~ust - 28 September. Such studies were carried out, in particular, on the Kolyma River, in the neighbor- hood of Cherskiy station, where simultaneously with measurements with a radiation thermometer fron~ a motor boat ~i mercury thermometer was used in measuring the tem- perature of the ~aa*~r surf~a e layer in the rive~. The discrepancy in water tempera- - ture measurements did not e.:~eed 0.2� (Table 1). I)uring the period of aerial temperature surveys it was also possible twice to carry out joint observations from aboard the expeditionary ship "Mayak." [The oceanograph- ic expedition of the Arctic and Antarctic Scientific Research Institute aboard the cxpeditionary ship "Mayak" was headed by A. V. Chireykin.) Water temperature at the surface and at tlie horizons 0.5, 1, 2 and 5 m was measured from shipboard. In both cases the water temperature in the upper 5-m layer was virtually identical. Meteor- ological obser.vations were made simultaneously (Table 2). Tlie differ.ence i.n data ubtained when measuring water temperature at the sea surface witli a PP.T-5 ttiermometer and the d'ata obtained on the "Mayak" ship in the first c~ise caas 0.1 and i.n tlie second case 0.4� (see Table 1). An aerial temperature sur- vey of the i.ce-free sea surface ~aas made on 22 September. The aircraft flight path 45 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007102109: CIA-RDP82-00850R000500020048-2 , FOR OFF'ICIAL USE ONLY duplicated the standard hydrological runs made from the ship "I~Iayak." Table 1 Temperature of Sea Surface Accordin~ to i�feasurements at Polar Stations, "Mayak" Ship and From Aircraft With PRT-5 Radiation Thermometer Date Region Temperature PRT-5 polar station or ship 15/August Cape Vankarem 2.6; 2.4; 2.1 0.5 Y.olyuchin Island 2.1; 1.6; 2.3 ~�8 Ayon. Island 2.5 1.8 Ambarchik Bay 11.0 9.3 20/August Ayon Island 1.2 0.6 Chetyrekhstolbovoy 3.2 2�3 Kolyma River, Cherskiy 11.0 10.9 30/August Chukotskoye i~fore ("Mayak") 1.0; 1.0 0.9 31/August Kolyma P.iver, Cherskiy 8.0 ~�8 17/September Kolyma River, ~herskiy 1.8 1.9 21/September Kolyma River, Cherskiy 2.2 2�~ 22/September Chukotslcoye More 1.7; 1.4; 1.5; 1.4 1.1 n~yak~i Table 2 Meteorological Conditions According to Observational Data Obtained From Aboard the "Mayak" at Time of Joint Work With Aircraft Date Air temperature, Relative humid- Wind State of ity, % direction velo- sea, units city, m/sec 30/Au~ 3.6 95 S 8 2 22/Sep 1.8 93 W 3 3 Figure 1 presents the results of observations obtained using the PRT-S and a ship on one such section with an extent of about 200 miles. The expeditionary ship "Mayak" occupied oceanological stations each 30 miles. Readings on the hand indi- - cator were made on the average each 6.5 miles of flight. Registry on the tape of a KSP-4 potentiometer was uninterrupted. ' The substantial difference in the data obtained from aboard the shig and using the PRT in individual se~ments of the profile is attributable to the fact that the ob- servations were made at different times. Due to the considerable time required for running the profile (19-28 September) and the great distance between stations the ship data have a smoothed character. The observational data obtained using the 46 ' FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2047/02/09: CIA-RDP82-00850R400504020048-2 FOR OF'FICIAL USE ONLY radiation thermometer indicate a more complex structure of the temperature field. t;C e s 1 , : / \ : 2 _ ~ f \ 3 3 ~ j ~ j~ ~ / ' 1� f . miles ~ _ _1 '1_'--_. _i-._._.. _ _.L-"_ __.1..__-_._y L ~YNDN 3O gp 90 120 150 I80 210 Fig. 1. Change in water temperature at sea surface along standard profilf~. 1) ob- servational data obtained from aboard "Mayak" ship; 2) discrete readings on hand - indicator of IR radiometer; 3) continuous registry on potentiometer tape. Aircraft sorties were made to polar stations for checking the accuracy of readings of the radiation thermoneter. At the time of aircraft approach to the station ~ simultaneous measurements were made of water temperature at the sea surface on the hand indicator of the radiometer and by tlie polar station observer. The results of measurements of water ter~perature are comc~unicated by the po?ar stations to the aircraft. The radiometer measurements had to be made precisely at the time of air- craft flight over the position of polar station observations. This was difficult to achieve. Taking into account that in the coastal re~ions the horizontal temper- ature gradients of ~:le ~aate*- are usually considerable, great discrepancies in the readings of the radiometer -~.d poiar station (see Table 1) are entirely natural. - During the exe~ution of ice reconnaissance leads were encountered on almost every fliglit; these were covered with young ice. If the young ice had the age stage of ice slush or ice crust or older, the radiometer measured the temperature of the surface of this ice. If ice needles were observed in the lead, it could be assumed tliat the tem~~erature at tlie surface of the lead has the freezing temperature of w;it~r.. In this case the radiometer readings were compared with the freezing tem- perature of water with tlie mean long-term salinity value for this region. An analysis of the results of aerial ter~perature surveys and methodological studies reveals that the instruments used meet the principal requirements of operation on board aircraft under. arc.tic conditions. The PRT-5 precise radiation thermometer has 47 FOR OFFICIAL US~ ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/42/09: CIA-RDP82-00850R000500020048-2 M~UR Uh'!''1l.lAL U~~: UNLY guod operational qualities, a liigli stahilit;~, insignificant inertia and stable reading. During the entire operating period the error in measurements with t'~is radio~eter did not exceed the value indicated in the certificate. Amon~ the shortcomings of the PRT-5 we should include the complexity of the cir- cuitry and the great number of highly sensitive elements, ~~hich results in a high cost of the instrument and lowers its reliability. Witli respect to design a rad- tion thermor~eter has an inadequate strength of the plu~s and contacts and an inad- equate hermetic sealing. During the time of operation of the PRT-5 radiometer there was one failure in its operation as a result of increased vibration and entry of moisture from the air into the optical head. This led to disruption of the con- tacts of the sensing elements. In general, however, the results of the work con- ~ firmed the accuracy of its measurements. This made possible extensive use of the PRT-5 radiometer for the collection of important information on temperature of the sea surface. The collected data were used in the scientific-operational support of sea operations. ~,C 1 and 2 ~ I M 2 ~ r- ~ _Z -3 I q ^ 2 -5 3 ~ 3 -e n 3 r-, n 3 n -e -e io n- -iz -i3 - ~ ~ ' ~ u ~ ~ g 4 6 4 b ~ ~ ~ ~ _ 0 ~ 2 3 r He mlri 4~.3 B~8 ~Z~B NM Fi~. 2. Fragment of record of surface temperature of ice cover on 28 September 1973. 1) slush ice; 2) dark ice crust; 3) light ice crust; one-year ice; S) field of perennial ice. During tlie flights specialists also made tests of a model of an IR thermometer devel- oped in the R~VT laboratory of tlie Leningrad Electrotechnical Institute in a port- able variant. A peculiarity of this instrument is the simplicity of the circuitry, low cost, strength and reliability in operation. The inadequacies include an 48 FOR OFFIC[AL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500024048-2 ~FOR OFFICIAL USE ONLY increased zero drift and a hroad transmission band of the optical filters. - The KSP-4 and potentiometers met the requirements of aerial temperature surveys. In addition to measurements of the water temperature at the sea surface, the radia- tion thermometer registered the surface temperature of the ice cover. The measure- ments which were made confirmed the idea expressed in [2] that the temperature of ice of different age is different (Fig. 2). Such a difference is a result of a de- crease in the heat flow from the water to the ~ipper surface of the ice with an in- crease in its thickness. In autumn and in winter at negative air temperatures the young ice is invariably warmer than the perennial ice. This fact is of unquestion- able interest and merits the closest attention in further investigations. Such in- vestigations will afford a possibility for study of the peculiarities of heat ex- - change between the ocean and the atmosphere throu~h the ice cover over a consider- able area. At the same time, the temperature contrast at the ice surface, depend- ing on its thickness, will make it possible to solve the inverse problem: use of - IR apparatus for determining ice of different age. However, at present there are still no data for any generalizations along these lines. For this reason the col- lection of data on temperature of the ice cover must be continued. For an objective interpretation of ice and preparation of new standards on the basis ~f data from IR apparatus it is desirable that such observations be supplemented by an aerial photographic survey along the flight route. In addition, it is important to clarify how the nature of the correlation between the therma.l contrast and ice age changes with transition of air temperature from nega`ive to positive values and also whether there is a sufficiently clear depend- ence between these characteristics in summer, when the ice surface is covered by a _ thin water film and patches of snow. The value of the observations is increased if the measure~aents with the radiometer are supplemented by direct measurements of tem- perature of the ice surface by highly sensitive contact sensors. Such data are nec- essary for experimental determination of the optical characteristics of the ice cover surface. In order to draw final conclusions concerning the correspondence between the temper- ature of the thin film and the temperature of the sea surface layer it is necessary to carry out specia~ method~logical investigations similar to the investigations described in [1]. They alsc, !iould include parallel measurements with a radiometer and the contact sensors of the expeditionary ship. It is particularly important to carry out such work in leads where there is thin or scattered ice since under these conditions the effect of wind mixing is lessened and as a result of the thaw- - ing of ice the stability of the water surface layer is increased. The organization oE such observations will also make possible a more precise determination of the influence of state of the atmosphere on radiometer readings. _ EIBLIOGRAP1iY 1. Vinogradov, V. V., "Some Results of Measurements of ~dater Temperature Distribu- - tion in the Surface Layer of the Northern Part of the Atlantic Ocean," TRUDY ~ OKEANOGRAFICHESKOGO It1STITUTA (Transactions of the Oceanographic Institute), No 100, pp 38-46, 1970. 49 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 - FOR OFFICIAL USE ONLY 2. Galkina, A. I. and Spitsyn, V. A., "Measurement of Surface Temperature of Water, Snow and Ice by a Radiation Thermometer," TRUDY AANII (Transactions of the Arc- tic and Antarctic Scientific Research Institute), Vol 295, pp 64-68, 1970. COPYRIGH~a; Arkticheskiy i antarkticheslciy nauchno-issledovatel'skiy institut (AANII), 1975 ~ SO - FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2407/02109: CIA-RDP82-00854R000500020048-2 FOR OFFICIAL USE ONLY STUDY OF DYNAMICS OF GLACIERS USING LASER DEFORMOGRAPH Leningrad TRUDY. ORDEtdA LENINA ARKTICHESKIY I ANTARKTICIiESKIY NAUCHNO-ISSLEDOVATEL'- SKIY INSTITUT. FIZICHESKIYE METODY ISSLEDOVANIYA L'DA I SNEGA in Russian No 326, 1975 pp 143-146 [Article by I. M. Belousova, I. P. Ivanov and N. G. Firsov] = [Text] This article is a discussion of some characteristics of a laser deformograph - and a~so the results of investigations which were obtained using this instrument - on glaci~ers in the neighborhood of Mirnyy station in Antarctica. The fundamental possibility of creating such an instrument was mentioned in [1,3]. Laborato ry and field investigations carried o ut using~a laboratory model of the in- strument in Antarctica, on the ice of Lake Lado ga and on the glaciers of the Cauc- asus made it possible to formulate the following requirements on individual instru- ment blocks. l. Its laser should be: a) single-frequency, s ince only in this case is the moaula- tion intensity of the output radiation not dependent on the distances to the inves- tigated object; b) single-mode, which ensures the necessary modulation intensity and makes it possible to avoi~ intermode beats [2]; c) stable with respect to radi- ation frequency, with adherence to the following condition: Q'~ ~ ~oZ'eff~L~ where 0 Leff is t}ie ~~easured sliift, L is the distance to the measured object, is the change in the ~requency ~f. laser radiation, as a result of system instability, is the laser radiatiori trequency. 2. The optical system of the instrume:it must include receiving and transmitting telescopes which are selected from the condition of full use of laser radiatian with reflection from the investigated object. 3. The registry system must iLlclude a photomultiplier (FEU), amplifier and spectrum analyzer, upon which special requirements are not ~_mposed. Our laboratory investigations made it possible to determine the limits of the rates of movement of the object to be determined, wh ich with respect to the upper limit are determined by the width of the rescnance line of the laser and are 1-2 MHz (0.6 m/sec), and which with respect to the lowe r limit are determined by the width 51 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2047/02/09: CIA-RDP82-00850R000504020048-2 FOR OF~ICIAL USE ONLY of the generation iine, whose theoretical width is determined b.y the specific con- ditions of the experiment and i~ a value about 1Q-3 Hz. Under natural conditions it is dependent on thermal deformations, the microphone effect, fluctuations of the atrto5phere on the radiation path. In addition, tiy means of laboratory investigations it was possible to determine absolute sensitivity to thP shift, whose minimum value j.n the case of use of a laser with a three-mirror resonator (unmatched) is 0.002�,in. Field tests of a model of the instrument in~Antarctica in the neighborhood of Molo- dezhnaya station during the period of operation of the lSth Soviet Antarctic Exped- ition [4] indicated that the instrument could perform in severe climatic situations and also that it is possible to determine the rate of movement of objects at dis- tances from 380 m. One of the important conclusions from this study was that the ' atmosphere over the glacier cover in Antarctica is exceedingly favorable for the carrying out of this type of interferometer measurements. As a result of what has been presented above, we designed and fabricated a laser deformograph. Laser Deformograph Operating Principle The laser radiation ~is directed through the forming optical system to a reflector mounted on the investigated glacier, and being reflected from it, returns to the instrument. The beats arising in the laser are registered by a photodetector; their frequency is determined by the recording apparatus. The instrument consists of three blocks: reflector, recording apparatus together with a power source for the entire apparatus, laser with a photodetector and with the optical system. The in- strument uses a specially developed single-frequency = 6328 A) helium-r.eodymium iaser with frequency stabilization which is created by control of the resonator by an error signal shaped using a neon absorbing cell in a magnetic field and a doubly refracting prism. The l~aser deformograph is intended for operation at distances up to 1.5 km. The ' very same 20X telescope is used as the transmitting and receiving optical system. The reflector, whose diameter is 200 mm, is a set of triple high-quality prisms (1"-3"). For a methodological comparison, and also for operation with internal frequency stabilization, a Michelson interferometer is incorporated in the in- - strument. By means of an eyepiece fitted directly into the instrument the laser radiation is visually directed to the reflector. The system operates in a mis- matched coupled resonator so that the ~fraction of light returned to the laser is small and the intensity of tliis radiation is modulated in conformity to a sinusoidal law. The period of modulation of the racliation corresponds to the Doppler fre- quency, related to the movement of the object by the formula ~ [OTP = refl] c1/== riR~T~ cos(2v ~ 1-f-~p) , where ~ I is the change in laser intensity; 1~0 is the frequency of laser radiation; v is the rate of movement of the object; c is the speed of light; I is the length of the resonator; a is the distance to the object; Rrefl is the coefficient of reflec- - tion wit'nin the resonator; RD = 1- T~ is the coefficient of reflection of the re- ' flector. 52 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/42/09: CIA-RDP82-00850R000500020048-2 FOR OFFICIAL USE ONLY ; Davis Sea MOPE QEi~BHCA ~ Sopka Vetr _ InstrumenL~P"6op ; conHa ; ' ; Bempoe' ~ ~ ~ _ , . / / ~ ~ il ~ ~ ~ / ~ , ~ ~i / / i--~~/ i ~ 1 / / ~ / 20/~ ~ ~ ~i~~ I I j ~50 i~ '~i~ ~ f / i / ~ ~i _ lr/ l 1 ~ 1 I%/~~ / j~~ ~ 1~ ~ 1 j ~ ~ I ~ ~ OTps~arens Pravda Coast 6EPEf f1PAB,qbl~ ~ ~ ~eflector ~ Fig. l. Diagram of investi~ated re~ion. Calibration was accomplished by means of a specially developed simulator of move- ment based on thermal expansion. By means of the simulator the translational move- ~ ment along a guide with rates fro~a 0.5�m/sec to 100~tm/sec is communicated to the triple prism reflector. This instrument was tested in operation during the seasonal period of the 18th Soviet Antarctic Expedition in Antarctica in the neighborhood of P4irnyy station. The first step was to determine the instrument`s effective range, that is, a deter- mination of the xnaximum distance at which laser radiation does not lose its coher- ence property. It w~.s discovered that with the passage of radiation through a layer of the atmosphere w:ith a thickness up to 2 lcm the coherence of the radiation is not impaired. Measurements of atmospheric transparency were mad~ for radiation with a = 6328 A. _ Atmospheric transparency was determined at different times of day during the period - . from 20 January ~!.~ough 20 June 1973. A correlation was found between atmospheric transparency for T= 6328 A and the meteorological range of visibility. It can be concluded from these experiments that atmospheric transparency is very high and virtually all the laser rad~~*_ion passes through the atmosphere, that is, there is confirmation for the concl~.:sion drawn during the period of operation of the 15th Soviet Antarctic Expedition that the atmo~i>liere over the Antarctic glacier is very - favorable for interferometer measurements of this l~ind. An outlying camp for study of movement of rlte glacier cover was organized in the neighborhood of the small flill of the Winds (Sopka Vetro~~) (Fig. 1). The instrume~nt was set up directly in tlie tent on bare rock, together with apparatus for adjusting and checlcing individ- ual instrument components,. Al1 the apparatus caas supplied current from a Qasolene- powered generator. The rates of movement of different points on ~ne glacie were determined (distant up to 1 km from the rocks). - The registered oscillograms were used in computing the rate of movement of son~e point on the glacier during the time of observation; this varied in the range from 0.5~,Lm/sec to 1.2 ~m/sec. In some cases it can be seen from the oscillograms that 53 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2 APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R040500020048-2 FOR OFFICIAL USE ONLY the rate of movement of this point on the glacier is not constant even during the observation ti2ne, that is, during a time of ahout 10 sec. Thus, the laser deformograph, successfully undergoing tests under field conditions in Antarctica, makes it possible to obtain new data Qn tfie movement of the glacier cover and undoubtedly in the future it can be used in solving many glaciological problems. BIBLIOGRAPHY l. Belousova, I.M., Bogorodskiy, V. V, and Ivanov, I. P., "Measurement of the Rate of Movement and Deformation of Glaciers Using Doppler Systems," TEZISY DOKLADOV NA XV GENERAL'tdOY ASSAI~IBLEYE P4GGS (Summaries of Repor~s at the Fifteenth General - Assembly of IQSY), Moscow, 1971, 47 pages. 2. Belousova, I.M., Danilov, 0. B. and Lyubimov, V. V., "Intermodal Seats in the Low-Frequency Spectral Region," ZHURid. TEK1iN. FIZ. , I1o 6, p 1134, 1967. 3. Belousova, I.t4., Bogorodskiy, V. V., Danilov, 0. B. and Ivanov, I. P., "Investi- gation of the Dynamics of Movement of Glaciers Using a Laser," DOKLADY AN SSSR (Reports of the USSR Academy of Sciences), Vol 199, No 5, pp 1055-1057, 1970. 4. Ivanov, I. P, and Chudakov, V. I., "Possibility of Determining the Rate of Move- ment of Glaciers Using the Doppler Effect in a Laser," ItdFORM. BYULL. SAE (Inf~rmation Bulletin of the Soviet Antarctic Expedition), No 8, pp 143-�146, 1973. COPYRIGHT: Arkticheskiy i_ antarkticheskiy nauchno-issledovatel~skiy institut (AANII), 1975 5303 - END - CSO: 8144/0319 54 FOR OFFlCIAL USE ONi.Y APPROVED FOR RELEASE: 2007/02/09: CIA-RDP82-00850R000500020048-2