AIDJEX Bulletin #40 - Polar Science Center - University of Washington

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nics occupy about 12 feet of the 17.5 foot long tube which extends 3 feet above the ice, Thus the electronics are all below the surface. The tubes extend 3 feet above the ice to prevent possible flooding from melt ponds which xcur on the ice surface in the summer. The primary batteries are located in the outer 3 tubes and occupy approximately 14 feet of vertical space thus the batteries are also below the surface of the ice. These tubes are the support for the upper structure and provide enough buoyancy to maintain the system at approximately the same level even in a full melt condition. The upper structure consists of 6 twelve foot radials with their supporting arms; a 6 inch diameter 12 foot long sleeve which provides the mounting structure for the temperature sensors, the VHF Beacon antenna, the NAVSAT antenna, the strobe light and acts as the feed line for the H.F. whip antenna. The H.F. whip is 24 feet long and is center loaded for the 4.1653 MHZ transmit frequency. The abbreviated radial system was used in an attempt to minimize the effect on antenna impedance of possible shifts in the ground plane due to summer melt condition. The chains at the ends of the radials are used to dampen wind-induced vibration. The antenna structure was grounded to sea water through the battery tubes. The temperature sensors are located nominally at 1 meter and 3 meters above the ice surface in radiation shields attached to the sleeve. The strobe light, NAVSAT antenna and VHF Beacon antenna are spaced120' at the top of the sleeve to minimize structural interference effects and to improve line of sight range. DEPLOYMENT The AEB's were deployed using a Twin Otter fixed wing aircraft equipped with skis. A multiyear ice flow in the desired location was selected and reconoitered for a suitable landing site. After landing,small pilot holes were drilled to determine ice thickness. If a suitable thickness of 8 to 12 feet were found, the installation was begun. Holes were drilled thru the ice for the four 8" diameter tubes using a 9" ice drill. The tubes were installed and the primary batteries loaded into the outer tubes using a tripod. These primary batteries could not be pre-loaded prior to installation because they are wet cells and could not be carried horizontally in the aircraft. The central electronics tube was preloaded however, and was placed in operation prior to leaving the AIDJEX main camp. The electronics were running on their internal secondary battery bank, in some cases continuously for 3 weeks, prior to deployment. This procedure obviated the need for turn-ON and extensive checkout in the field. While the tubes were being installed the upper antenna structure was being assembled. The upper structure was then placed on the tubes and electrical connections were made between the electronics tube and the batteries and antennas. A brief check was then performed to be sure that the H.F. transmitter, NAVSAT receiver and Location Aids were operational. Installation time averaged about 3.5 hours with a 3 man installatlon team and occasional assistance from the pilots. The installation of 8 AEBs was accomplished over a period of two months with the biggest delay due to weather. Their approximate positions along with that of the AIDJEX main camp are shown in Figure 3. CONCLUDIHG REMARKS Eight AEBs are now operational on the Arctic Ice Pack. These buoys are presently being used to gather data necessary to finalize a mathematical model of the ice pack. As such, they provide barometric pressure temperature and position data on a 3 hour synoptic schedule at a fraction of the cost of manned camps at similar locations to gather data. The AEBs have been designed with the flexibility to easily adapt to a wide variety of other sensors and can be used wherever periodic data over a long term is needed. The design and development of the AEB system and three prototype buoys was funded by the NOAA Data Buoy Office and the fabrication of the remaining AEBs and the Central Control Station was funded by the National Science Foundation through the AIDJEX Project Office. ACKNOWLEDGEMENTS An essential feature contributing to the success of the program was the close liaison and engineelring and scientific contributions by the AIDJEX staff members during the development phases of the program. In particular a debt of gratitude is owed to Pat Martin, the AIDJEX technical coordinator, for his dedication in reviewing and critiquing the design and for his devotion to the difficult task of completing the installation of the 8 AEBs in the Arctic ice pack. REFERENCES ITS Propagation Studies for Polar Research Lab DTD 10123173 AKIMA, H., "Modulation Studies for IGOSS", ESSA Technical Report ERL 172-ITS 110, June 1970 Hatfield, D. N. and DeHass T., "System Design Considerations for the Development of the IGOSS Ocean Data HF Transmission System", ESSA Technical Report ERL 158-ITS 101, March 1970 . Coachman, L., "Water Masses of the Arctic" Proceedings of the Arctic Basin Symposium, Arctic Institute of North America,,Page 145, October 1962 Maykut, G. and Untersteiner, N., "Numerical Prediction of the Thermodynamic Response of Arctic Sea Ice to Environmental Changes", Page 54-57, Rand Corporation Memorandum RM-6093-PR. November 1969 Brown, W. P., ''AIDJEX System Phase I, Final Test Report for Ice Island T3 Antenna, Battery and Structure Tests", Polar Research Lab, Inc., Report TR005, October 1974 18 IEEE OCEAN '75 - !X3
Sensor Word Description - Bits TABLE I Description NAVSAT Word sync 24 Sync Buoy I.D. 4 Buoy I.D. Julian Day # 10 Julian Day Word I.D. 1 Word I.D. Word # 4 Word # Engr Data 5 Engr Data Press Sensor #I 10 Buoy,Time of Day Press Sensor 12 10 Satellite I.D. 3 Meter Temp 10 Re1 ZULU Time (SAT) 1 Meter Temp 10 Doppler Count 81 Spare $1 10 Doppler Count 12 Spare #2 - 10 Doppler Count 13 Total 108 Doppler Count 64 Doppler Count #5 Total - Bits 24 4 10 1 4 5 14 5 5 24 24 24 24 54 - IEEE OCEAN '75 19
Page 2 and 3: DATA BUOYS AIDJEX BULLETIN No. 40 J
Page 4 and 5: NOTE TO FRIENDS, AND BYSTANDERS . .
Page 6 and 7: SUMMARY OF TECHNICAL DEVELOPMENTS I
Page 8 and 9: milestones, kept the vendor working
Page 10 and 11: The scene during deployment of HF-N
Page 12 and 13: The initial AIDJEX scientific plan
Page 14 and 15: poizr-orbiting satellite, which is
Page 16 and 17: t@ the spacecraft during each orbit
Page 18 and 19: BUOY NAHE COMMUN. COMMANDS FIXES TA
Page 20 and 21: L( 0 I 2 3 4 3 Radial error, kilome
Page 22 and 23: The buoy will be subjected to tempe
Page 26 and 27: Ill -- - KEY AIUJEX WIN WW AEBa 0 4
Page 28 and 29: event that a melt pond should form
Page 30 and 31: chute supplied by Paranetics Inc. i
Page 32 and 33: 6'" IqORGANIC LITHIUM BP.TTEI?Y IMP
Page 34 and 35: OM (AD RAMS) UREMEN~ \ AIRDROP N m
Page 36 and 37: provides a grid from which geostrop
Page 38 and 39: words; a four-bit air temperature w
Page 40 and 41: PERFORMANCE OF MET/OCEAN BUOYS IN A
Page 42 and 43: Sensor samples were taken every thr
Page 44 and 45: strengths are known, were used with
Page 46 and 47: the ice (causing reduced shear). An
Page 48 and 49: (McPhee, Mangum, and Martin) , TABL
Page 50 and 51: 70°N 75'N n 3 P 17OOW (D Y 170°W
Page 52 and 53: 12OOW * U Station 25. Xeasurements
Page 54 and 55: (McPhee , Mangum, and Martin) 2701
Page 56 and 57: (McPhee, Mangum, and Martin) a 0 a
Page 58 and 59: "i BUOY 4 I 43 360- 309- 257 206 15
Page 60 and 61: a30gl 251 I 60 511 r 43 BUOY 4 I
Page 62 and 63: n 4, (McPhee, Mangum, and Martin) 8
Page 64 and 65: (McPhee, Mangum, and Martin) 33 W c
Page 66 and 67: . '-,..I.. . B A R R O W W I N D S
Page 68 and 69: :
Page 70 and 71: I 25 23 t h--:!li[ NCI PiHCEl4l 22
Page 72 and 73: .5 .4 .3 0 A R 2 R 0 W J - 0 B U -
Page 74 and 75:
9 1.5 1.0 c 8 w .5 R 930 $ 565 1000
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Clock corrections were applied rout
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Q) u o z z i 4- 4- Z + + z f n 9 Ef
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TABLE 1 DIFFERENCES IN DAILY TEMPER
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Laboratory calibration of the ADRAM
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3.20- - 1 t W o? 2 3.051 ...:-.;..
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POSITION MEASUREMENTS OF AIDJEX MAN
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some redundancy. Four points were u
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75.5 75.: - E75.1 LLI % y75.c - 1 1
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The translocation principle removes
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POSITION ACCURACY To evaluate the q
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TABLE 1 STAND-ALONE ACCURACY 68th P
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Az i mu t h s When both receivers a
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DATA PROCESSING Following the field
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model ice motion in the statistical
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FREC 1 INCY / DOPPLER / FREQUENCY /
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35 30 25 v) > 0 2 20 LL 0 r= E m 15
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An example of a large-scale buoy ar
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observations are needed in remote a
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useful for determining how various
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as well as velocity fields, we must
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Since small changes in the yield su
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The transformation of the system of
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e able to judge how well such a mod
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then the flow rule becomes Q = +A -
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[-B' -F Finally, we eliminate Carte
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differential equation. 2. Discontin
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Substituting (36) and (37) into (34
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arbitrarily assign the values of 1
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The special case when advection can
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TABLE 1 STRETCHING, STRESS, ASP CHA
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ate of deformation, we have normali
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CHARACTERISTIC EQUATIONS The ordina
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One way to circumvent the problems
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The equations governing solutions a
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It is readily seen that when body f
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which may be substituted into equat
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a the stress derivative dCldS remai
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Although we have not studied in thi
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Courant, R., and D. Hilbert. 1962.
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A RESEARCH PLAN TO TEST THE AIDJEX
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the barges managed to reach their d
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APPROACH A baseline simulation 0-f
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SENSITIVITY OF ICE RESPONSE TO DIFF
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Since free drift of ice is computed
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and what is observed becomes less i
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stresses appear to be relatively un
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ehavior is directly related to accu
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TABLE 1 COMPARISON OF ESTIMATED ERR
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a) Base line b) 24-hour prediction
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\ / a) Base line b) 24- hour predi
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a) Base line b) 24- hour predi ct i
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Page 180 and 181:
\ / a) Base line b) 24-hour predict
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.. a) Base line b) 24- hour predict
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J2 a) Base line b) 24-hour predicti
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) 24-hour prediction c) 36-hour pre
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Page 190 and 191:
8 Figure 17. AIDJEX surface pressur
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APPENDIX 1 AIDJEX DATA FILES 1. Pos
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9A. Surface-1 eve1 ai r pressure (d
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19. Surface pressure (Val i dated)
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APPENDIX 2 AIDJEX DATA TRANSFERRED
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I -7-71327GEO A Cards (continued) 7
Page 202:
B Cards (continued) 201
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AIDJEX Bulletin #40 - Polar Science Center - University of Washington

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