ALBERT

Description / Table of Contents: This report first discusses the general approach for calculating the horizontal forces an ice cover exerts on a structure. Ice force determination consists of two parts: (1) the analysis of the in-plane forces assuming that the ice cover remains intact and (2) the use of a failure criterion, since an ice force cannot be larger than the force capable of breaking up the ice cover. For an estimate of the largest ice force, an elastic plate analysis and a failure criterion are often sufficient. A review of the literature revealed that, in the majority of the analyses, it is assumed that the failure load is directly related to a 'crushing strength' of the ice cover. However, observations in the field and tests in the laboratory show that in some instances the ice cover fails by buckling. This report reviews the ice force analyses based on the buckling failure mechanism and points out their shortcomings. The report then presents a new method of analysis which is based on the buckling mechanism

Description / Table of Contents: Abstract: Measurements of the concentrations of Aitken nuclei in maritime air were made near Barrow, Alaska, in June 1975 with a modified Nolan-Pollack small-particle detector. The concentrations varied from 50 to 300 particles cm^-3 depending upon meteorological conditions. The mean Aitken nuclei count was 100 particles cm^-3 for diameters greater than 2 x 10^-3 μm. Transmission electron micrographs of aerosols in maritime air near Barrow were taken. The size range was measured to be 0.01 to 2.5 μm in diameter with the most frequently observed diameter being 0.04 μm. The volume of the maritime air and the collection efficiency of aerosol particles on filmed grids for electron microscopy were measured. The aerosol concentrations were found to be 76 to 101 particles cm^-3 ; the mean concentration was calculated to be 87 particles cm^-3. The aerosol particles in the maritime air were identified by electron microscopy and selected area electron diffraction analysis. About 20% of the aerosol particles were identified, and 80% of the particles were too small for electron diffraction analysis. Sea salt particles constituted 2% of the total, and clay minerals 3%; these particles were considered to be of natural origin. Solid combustion by-products such as coagulated carbon particles and fly ash particles constituted 16%. Despite the comparative remoteness of the sampling site, the measurements indicate that many anthropogenic aerosols were found using an electron microscope.

Description / Table of Contents: A model investigation of drifting snow conditions was conducted in a hydraulic flume using a sand-water analog. Model results were evaluated to define modeling parameters that would allow quantitative correlation between measured prototype drift conditions and the model. The modeled structure was the standard plan snow fence designed by the Wyoming Highway Department and installed along Interstate Highway 80 in 1971. The performance of this system was documented by the Rocky Mountain Forest and Range Experiment Station of the U.S. Forest Service. Models of the fence were constructed for three heights and two geometric scales. Geometric scaling was based on terrain roughness and boundary layer thickness considerations, while velocity scaling was based on particle fall velocity and threshold of motion characteristics. Simulation of the atmospheric boundary layer was found to be of primary importance. Velocity scaling analysis suggested the use of a 'significant wind' concept based on a combination of velocity magnitude and frequency. Similarity of precipitation rate was not essential, and could be altered within limits to adjust the time scale. The response of the model to the shape of model elements was significant. Although the model is distorted and inexact similarity is achieved, it appears useful on a practical basis.

Description / Table of Contents: Road test sections of membrane-enveloped silt and clay soils overlain with asphalt cement concrete were subjected to repetitive dynamic plate-bearing loadings to determine their strength variations during freeze-thaw cycles. The recoverable surface deformations in the load deflection bowl were continuously measured during the loading cycles and analyzed using the Chevron layered elastic computer program to obtain the in situ resilient deformation modulus of the various section layers at different stages of the freeze-thaw cycles. The resilient stiffness of the pavement system (the total load per unit of resilient load plate deflection) was also calculated for the various freeze-thaw conditions. The modulus values of the asphalt cement concrete varied inversely with its temperature by an order of magnetide (90,000 psi to 1,300,000 psi). The resilient stiffness of the pavement system varied in the same manner by nearly a factor of eight (228.4 kips/in. to 1740.2 kips/in.). Despite the wide strength variations of the sections during freeze-thaw cycles, membrane-enveloped fine-grained soils can be utilized instead of granular materials as base and subbase layers in flexible pavements in cold regions where moisture migration is a major concern. Moisture migration did not occur at saturation levels up to 75%, thus there was no strength loss during thawing.

Description / Table of Contents: Results of measurements of salinity, grain size, substructure dimensions and crystal fabrics of the undeformed 2.15-m-thick annual sea ice sheet near Narwhal Island, Alaska, are presented. A notable observation was the formation of a dominant c-axis horizontal structure in all ice below 14 cm, including transformation to a pronounced east-west alignment of the c-axes by a depth of 66 cm. This study confirms earlier reports of the occurrence of very strong horizontal c-axis alignments in arctic fast ice.

Description / Table of Contents: The mathematical theory for the bearing capacity of river ice for vehicles is presented. The floating ice sheet is assumed to have simple supports at the shore line. Solutions are presented for loads uniformly distributed over circular and rectangular areas. Numerical evaluations are made for a number of vehicles and the results presented in graphical form

Description / Table of Contents: The results of axial double point-load tests on disk samples of snow and ice obtained from the area of McMurdo Sound, Antarctica, are presented. They show the effects of temperature, sample length, load point diameter and specific gravity on failure load. It was determined that 13 samples should be tested to obtain a representative mean strength index. The results show that the axial double point-load test has good possibilities as a rapid field test for determining the unconfined comrpessive strength of snow and ice but that further evaluation of the variables affecting test results must be made.

Description / Table of Contents: Abstract: Ageneral computer model to simulate municipal snow removal has been developed. Programs which aid in the routing of snowplows are a part of this package. Once vehicle routes are created, the simulation program can be used to assess situations varying both equipment and meteorological parameters. Time for each plow to complete its route is calculated. Considerations are made for the above variable parameters plus plowing windrow, route starting depth, overlapping truck routes and intersection delay time. The effects of storm length, snowfall rate and starting depth on total plowing time are examined in a test case.

Description / Table of Contents: Ten roofs in Concord, New Hampshire, were surveyed for wet insulation using a hand-held infrared camera. Suspected wet areas were marked on the roof with spray paint and roof samples were obtained to verify wet and dry conditions. Recommendations for maintenance and repair were made based on infrared findings, water contents, and visual examinations. An incremental economic study is presented to serve as a guide in determining the most cost-effective approach.

Description / Table of Contents: The report deals with the cutting of rock and similar materials by parallel motion tools. It examines cutting forces and energy requirements, taking into consideration tool geometry, wear, operating conditions, and material properties. After an introductory discussion of terminology, some general principles are outlined, and relevant theoretical ideas on metal cutting and rock cutting are reviewed. The next section, which is the heart of the report, reviews experimental data on the magnitudes and directions of cutting forces. There is a graphical compilation of data, including some from obscure or unpublished sources. The variables covered include chipping depth, rake angle, relief angle, side rake, base angle, tool width, tool compliance, tool speed, tool wear, tool interactions, and material properties. The second major part of the report treats the energetics of cutting. It begins with a short discussion of relevant principles, and continues with a compilation and review of experimental data, covering the same independent variables as the force section. The report ends with a concise summary of general behavior for parallel motion tools.

Description / Table of Contents: During the past decade a number of methods for measuring the amount of unfrozen water in partially frozen ground have emerged. Means of quickly and simply predicting unfrozen water contents in clay have become increasingly important with the growth of interest in encapsulating clay soils compacted at low water contents to serve as base courses for roads. Unfortunately the measurements require sophisticated equipment and, in most instances, specially trained operators. In an effort to simplify the task of obtaining water-ice phase composition data, methods of calculating phase composition curves from other, simpler measurements on soils have been sought. The paper presents a method of deriving the measurement of unfrozen water contents at various temperatures from liquid limit determinations.

Description / Table of Contents: A commercial deep-freeze unit was modified to serve as a laboratory for growing single crystals, cutting specimens of a given orientation, testing these specimens in compressive creep, and studying thin-sections of the results on a universal stage. A method of growing single crystals of adequate size was developed by adapting the Bridgman method. Fortyone creep tests were made at temperatures ranging from -1° to -18°C. These gave an unexpected form of creep-curve in which the rate of strain continuously increases with time. The mechanism of deformation is dominantly basal translation—consistent with earlier work. The dependence on temperature and stress is expressed empirically.

Description / Table of Contents: Work carried out at the SIPRE Test Site, Site 2, on the Greenland Ice Cap,during the summer 1954, included: (1) Excavation of trenches, a circular tunnel and a deep pit; (2) Instrumentation of excavations for pressure and deformation measurements; (3) Tests on the properties of snow from the deep pit; (4) Construction of a snow house as an experimental structure and to provide a heated shelter for an observer stationed at the site for the winter. Observations and measurements over a period of five years are expected to provide sufficient information for the establishment of satisfactory design criteria for all kinds of surface and subsurface military installations on high polar ice caps.

Description / Table of Contents: Water flow through the vein structure of temperate ice is described as Darbian flow in which the pressure gradient is determined from vein size and overburden pressure. A solution method for the resulting equation is given and two special cases are considered. For steady flow the equilibrium vein size is a function of depth and, by neglecting the effects of diffusion, it is shown that flow perturbations introduced at the surface propagate downward at a constant speed.These perturbations propagate so slowly that even annual surface fluctuations of flow may be eliminated by diffusion before reaching the bottom of the glacie

Description / Table of Contents: Access to study areas may be an important factor in long-term field-oriented research, particularly in-regions without well-developed road and communications systems. In a wildland hydrometeorology research project in subarctic Alaska, access to and within a 40-square-mile research watershed has been developed both in accordance with a general plan prepared at project inception and in response to developing research requirements. Foot trails, trails for 'off-road' low-ground-pressure tracked vehicles, helicopter transport, long-term data recorders, and radio telemetry of data have all been incorporated in an access and communications system. Cost estimates indicate that incorporation of gravel roads into the system would be economically advantageous, given adequate funding for initial road construction.

Description / Table of Contents: Water flow through the unsaturated portion of a snowpack is calculated using various assumptions about radiation penetration into the snow. The results show that for the purposes of hydrologic forecasting, it is sufficiently ac­curate to assume that all of the radiation absorption occurs at the surface. The error in the calculation of flow is largest for very shallow snowpacks, but this error is reduced by radiation absorption at the base of the snow and by the routing of meltwater through the saturated basal layer.

Description / Table of Contents: The thermal structure and ice conditions of Lake Champlain, a mid-latitude large lake, near Shelburne Point, Vermont, were studied during the winter of 1974-75. The lake was instrumented to a depth of 8.5 m with a string of highly calibrated thermistors, connected to a data logger on shore which recorded water temperatures every four hours. An ice mooring system was developed to anchor the thermistor string so that ice and water temperatures could be obtained at known levels. This temperature recording system measured vertical and horizontal variations in ice and water temperature regimes during ice formation, growth and decay. Meteorological data were measured during the winter period November 1974 through March 1975 at the site. Ice stratigraphy was determined for the ice at the site at its maximum seasonal growth for comparison with ice from St. Albans Bay (at the northern end of Lake Champlain) which had formed earlier. Correlations were determined between ice growth and accumulated degree days of freezing. The operation of a bubbler system installed near the measurement site around a service dock was observed.

Description / Table of Contents: A literature review of revegetation and biological aspects of restoration research was completed for arctic and sub­arctic North America. Although there is a great deal of climatic variation in this region it is generally characterized by extreme conditions, such as a short growing season and permafrost. Most of the revegetation research has been undertaken in the last six years as a result of increased natural resource development. The primary goal has been erosion control, with aesthetics, minimization of thermokarst, and production of browse as other objectives. Revege­tation and long-term restoration methods depend upon such variables as the site conditions, nutrient regime (especially as this is influenced by the climatic conditions in the Arctic and Subarctic), plant adaptations, and the selection of native or introduced species. Technologies which have been developed to meet these conditions primarily include seedbed preparation, use of seed mixes, and fertilization and seeding methods. Most of the research has focused on the use of agronomic grasses and legumes. These are selected on the basis of a number of factors, such as cold hardiness and growth form prior to evaluation in the laboratory and the field. The most successful species to date have been Arctared fescue and Nugget bluegrass in the Arctic, while these two as well as creeping red fescue, meadow foxtail, Frontier reed canarygrass, Durar hard fescue, slender wheatgrass, and Icelandic poa did well in the Subarctic. Similar methods have been attempted to a more limited extent with evaluation of native herbaceous and woody species which seem promising on the basis of natural succession studies. There are a number of continuing research needs for arctic anc subarctic revegetation. These include fertilization strategies, development of specialized techniques (such as sprigging) for native species, and longer term studies. It is particularly important to integrate short term revegetatio methods with long-term restoration goals.

Description / Table of Contents: CONTENTS: Abstract. - Preface. - Introduction. - Discussion of heat loss survey of six housing units. - Survey of base facilities. - Conclusions. - Literature cited.

Description / Table of Contents: During the winter of 1973-74 a mobile infrared thermography system was used to survey housing units and base facilities at Pease Air Force Base, Portsmouth, New Hampshire. This report provides both qualitative and quantitative evidence regarding heat flow out of the eave vents of these housing units. Calculations indicate that a significant amount of heat is being lost in this manner due to inadequate attic (cap) insulation. Possible evidence of incomplete ventilation could explain the presence of condensation in the housing units. Analyses of thermograms are presented to show the possible existence of low and high pressure areas around a structure and how they relate to heat loss.

Description / Table of Contents: Contents: Report of the commanding officer. - Appendices. - 1. War Department order assigning Lieutenant Greely to command. - 2. War Department order organizing the expedition. - 3. Instructions from the Signal Office regarding the expedition. - 4. List of commissary subsistence stores, with remarks thereon. - 5. Records left at and taken from Southeast Cary Island, August, 1881. - 6. Lieutenant Kislingbury's report of trip to Life Boat Cove. - 7. Records taken from and left at Washington Irving Island, August, 1881. - 8. Records obtained at Discovery Harbor, August 1, 1881. - 9. Lieutenant Lockwood's report on Water-course Bay, August, 1881. - 10. Lieutenant Kislingsbury's request to be relieved, with Lieutenant Greely's indorsement. - 11. Orders No. 5, relieving Lieutenant Kislingsbury and ordering him to report to the Chief Signal Officer. - 12. Orders No. 6 amending Orders No. 5. - 13. Lieutenant Kislingsbury's request for modification of Orders No. 6. - 14. Orders No. 8 modifying Orders No. 6. - 15. Lieutenant Lockwood's report on exploration of St. Patrick Valley. - 16. Sergeant Brainard's report establishing Depot B near Cape Beechy. - 17. Sergeant Jewell's meteorological report in connection with trip establishing Depot B. - 18. Sergeant Gardiner's report of trip to Cape Murchison. - 19. Sergeant Linn's report on moving Depot A to Cape Murchison. - 20. Orders to Dr. Pavy for overland journey to Lincoln Bay. - 21. Report of Dr. Pavy on trip to Lincoln Bay. - 22. Report of Lieutenant Lockwood on journey to the Bellows. - 23. Orders to Dr. Pavy on exploring Archer Fiord. - 24. Report of Dr. Pavy on attempted trip down Archer Fiord. - 25. Report of Lieutenant Lockwood on sledge journey to Depot B near Cape Beechy. - 27. Orders to Dr. Pavy to proceed to Cape Joseph Henry. - 28. Report of Dr. Pavy on trip towards Cape Joseph Henry. - 29. Lieutenant Lockwood's report on St. Patrick Valley. - 30. Sergeant Rice's report on camp equipage. - 31. Lieutenant Lockwood's orders to attempt crossing of Robeson Channel. - 32. Lieutenant Lockwood's report on attempted crossing of Robeson Channel. - 33. Dr. Pavy's orders for journey to Wrangel Bay. - 34. Dr. Pavy's report on journey to Wrangel Bay. - 35. Dr. Pavy's supplementary report under Appendices 27 and 33. - 36. Lieutenant Lockwood's orders for preliminary journey to Cape Beechy. - 37. Lieutenant Lockwood's report on journey ordered in Appendix No. 36. - 38. Lieutenant Lockwood's orders for journey to Thank God Harbor. - 39. Lieutenant Lockwood's report on journey ordered in Appendix No. 38. - 40. English records obtained at Thank God Rarbor. - 41. Dr. Pavy's orders to carry provisions to Greenland coast. - 42. Dr. Pavy's report on journey ordered in Appendix No. 41. - 43. Sergeant Brainard's orders to move boat to Greenland coast. - 44. Sergeant Brainard's report on trip ordered in Appendix No. 43. - 45. Sergeant Jewell's report on trip to Lincoln Bay while supporting Dr. Pavy. - 46. Dr. Pavy's orders for journey northward over Polar Ocean. - 47. Dr. Pavy's report on journey ordered in Appendix No. 46. - 48. Sergeant Rice's report on detached trip from Lincoln Bay to Fort Conger and return. - 49. Private Long's report on trip into Archer Fiord. - 50. Sergeant Israel's report on trip into the Bellews. - 51. Lieutenant Lockwood's orders lo explore north coast of Greenland. - 52. Supplementary instructions for exploration of north coast of Greenland. - 53. Lieutenant Lockwood's report on exploration of north coast of Greenland. - 54. Report of Private Biederbick's trip into Black Rock Vale. - 55. Sergeant Linn's report of trip into Black Rock Vale. - 56. Lieutenant Lockwood's report of launch trip up Archer Fiord. - 57. Lieutenant Lockwood's report of launch trip up Chandler Fiord. - 58. Dr. Pavy's orders to proceed to Carl Ritter Bay. - 59. Sergeant Elison's report of trip to Carl Ritter Bay. - 6o. Sergeant Brainard's report of trip to Carl Ritter Bay. - 61. Orders establishing day of "Thanksgiving". - 62. Dr. Pavy's Ietter of March 8, 1883. - 63. Lieutenant Greely's answer to Dr. Pavy's Ietter of March 8, 1883. - 64. Lieutenant Lockwood's orders for preliminary journey northward, 1883. - 65. Lieutenant Lockwood's report on journey ordered in Appendix No. 64. - 66. Sergeant Jewell's report to Lieutenant Lockwood relative to journey ordered in Appendix No. 64. - 67. Orders to Lieutenant Lockwood for exploration of Greenland, 1883. - 68. Sergeant Rice's orders for journey to Thank God Harbor. - 69. Dr. Pavy's orders for journey, as surgeon, to Thank God Harbor. - 70. Lieutenant Lockwood's report on trip to North Greenland. - 71. Sergeant Jewell's report on tidal and meteorological observations made on trip to North Greenland. - 72. Sergeant Rice's report on trip to Thank God Harbor. - 73. Dr. Pavy's medical report on trip to Thank God Harbor. - 74. Orders for Sergeant Jewell for tidal observations at Cape Beechey. - 75. Report of Sergeant Jewell on tidal observations at Cape Beechey. - 76. Orders for Sergeant Gardiner for tidal Observations at Cape Baird. - 77. Orders for Sergeant Israel for astronomical Observations at Cape Baird. - 78. Report of Sergeant Israel on observations ordered in Appendix No. 77. - 79. Report of Sergeant Gardiner on tidal and ice observations at Cape Baird. - 80. Report of Sergeant Jewell on paleocrystic ice. - 81. Orders to Sergeant Jewell for tidal Observations at Cape Beechey. - 82. Report of Sergeant Jewell on tidal Observations at Cape Beechey. - 83. Sergeant Brainard's report on journey to Cape Cracroft. - 84. Sergeant Gardiner's report on journey to Cape Cracroft. - 85. Lieutenant Lockwood's orders to cross Grinnell Land. - 86. Lieutenant Lockwood's report on the crossing of Grinnell Land. - 87. Orders to Dr. Pavy relative to natural history data. - 88. Orders to Dr. Pavy relative to botanical specimens. - 89. Orders to Lieutenant Lockwood to relieve Dr. Pavy as naturalist. - 90. Lieutenant Lockwood's report on natural history specimens received from Dr. Pavy. - 91. Lieutenant Lockwood's Ietter and report on natural history specimens, June 30, 1883. - 92. Sergeant Brainard's report on Lieutenant Lockwood's trip towards the United States Mountain range. - 93. Orders to Lieutenant Lockwood to receive medical stores from Dr. Pavy. - 94 Letter of Dr. Pavy asking the detail of Steward Biederbick. - 95. Reply of Lieutenant Greely to Dr. Pavy's request for detail of Steward Biederbick. - 96. Letter of Dr. Pavy's, dated July 18, 1883. - 97.Answer to Ietter referred to in Appendix No. 96. - 98. Dr. Pavy's refusal to turn over his diary. - 99. Letter transmitting charges to Dr. Pavy. - 100. Letter limiting Dr. Pavy's bounds while in arrest. - 101 Order for the abandonment of station at Fort Conger. - 102. List of subsistence stores abandoned. - 103. Medical reports. - 104. Record left at Cape Baird. - 105. Records left in abandoned boats. - 106. Records found on Brevoort Island ( deposited by Lieutenant Garlington and Private Beebe). - 107. Plan of winter quarters, Camp Clay. - 108. Sergeant Frederick's report of November journey to Cape Isabella. - 109. Lieutenant Kislingsbury's letter, February 19, 1884. - 110. Private Long's journey into Hayes Sound. - 111. Sergeant Frederick's report of journey to Baird Inlet, April, 1884. - 112. Lieutenant Kislingsbury's letter, April 22, 1884. - 113. Letter of Dr. Pavy's, April 25, 1884. - 114. Letter of Dr. Pavy, April 27, 1884. - 115. Lieutenant Greely's certificate to Dr. Pavy. - 116. - General certificate to Dr. Pavy. - 117. Letter of Lieutenant Greely on Dr. Pavy. - 118. - Oder for Private Henry's execution. - 119. Report of Private Henry's execution. - 120. Letter of Secretary of War approving Lieutenant Greely's course regarding execution of Private Henry. - 121. List of deaths. - 122. Order relative to Private Henry, dated June 5, 1884. - 123. Lieutenant Lockwood's journal from August 3, 1883. - 124. Sergeant Brainard's journal from besetment. - 125. Portion of diary of Private Roderick R. Schneider, found on bank of Mississippi River, in Missouri, and correspondence relating thereto with Mr. J. A. Ockerson. - 126. Description of drift-wood. - 127. List of photographs and description of Eskimo relics in photographic plates. - 128 List of maps and charts. - Index to Vol. 1.

Description / Table of Contents: Table des Matières: Aurores boréales observées a Godthaab (1882-83) / Adam Paulsen. - Observations magnétiques faites a Godthaab (1882-83) / Adam Paulsen. - Les températures moyennes de l'eau de mer a la surface, pour les mois d'avril a septembre, sur les routes de la cote nord de l'Écosse a l'ile d'Islande et au Groenland / Adam Paulsen. - Observations météorologiques de Godthaab (1er Aout 1882 - 31 Aout 1883) comparées avec celles qui ont été faites pendant une série d'années sur la cote occidentale du Groenland / Adam F. W. Paulsen. - Flux et reflux de la mer a Godthaab calculés d'après une série d'observations horaires (16 Juillet - 31 Aout 1883) / C. Crone. - La longitude de Godthaab déterminée d'après les observations de MM. Falbe, Bluhme et Ryder / V. Hjort. - Observations de Godthaab / Adam F. W. Paulsen. - Observations météorologiques de Godthaab (1er Aout 1882 - 31 Aout 1883) et de la cote ouest du Groenland / Adam F. W. Paulsen. - Observations météorologiques faites pendant la dérive de la Dijmphna dans la Mer de Kara (1882-1883) / A. P. Hovgaard. - Observations météorologiques et nautiques faites a Nennortalik et a Angmagsalik par les membres de l'expédition de M. Le Capitaine G. Holm pour explorer la cote est du Groenland.

Description / Table of Contents: Table des matières: Introduction. - Observation météorologique. - Pression atmosphérique. - Température de l'air. - Température sur le sol. - Température du sol: 1° à 0,4 m., 2° à 0,8 m. et 3° à 1,6 m. de profondeur. - Humidité de l'air. - Direction et vitesse du vent. - Nébulosité, forme et direction des nuages, hydrométéores. Eau tombée. - Evaporation de l'eau douce. - Température sur le sol et à 6 cm. de profondeur. - Température de l'eau de la rivière. - Remarque diverses; couches des nuages à hauteur différente. - Observations météorologiques de l'année 1883-84 faites à Sodankylä. - Remarques diverses 1883-84. - Observations météorologiques faites à Kultala. - Remarques diverses. - Aperçu général de moyennes mensuelles et de variations diurnes: variation de la pression atmosphérique, de la température de l'air, de la température sur le sol, de l'humidité de l'air, de la vitesse du vent, de la nébulosité et de l'eau tombée. - Fréquence des vents. - Les années 1882 - 83 et 1883 - 84 au point de vue météorologique.

Description / Table of Contents: CONTENTS: PREFACE. - NOMENCLATURE. - SUMMARY. - INTRODUCTION. - TECHNICAL BACKGROUND. - Rankine-Hugoniot Shock Equations. - The Rayleigh Line. - Release Cross Curves. - Impedance Match Technique for Measuring Hugoniots and Release Isentropes. - EXPERIMENTS. - Sample Materials. - Ottawa Sand. - West Lebanon Glacial Till. - Ice . - Sample Preparation. - Experimental Procedures. - EXPERIMENTAL DATA AND RESULTS. - Ottawa Sand. - West Lebanon Glacial Till. - Ice. - Release Cross Curves. - Dry Ottawa Sand. - Saturated Ottawa Sand. - Ice. - SUMMARY AND RECOMMENDATIONS FOR FUTURE WORK. - REFERENCES.

Description / Table of Contents: To compute shock wave propagation in frozen soil-water mixtures it is necessary to know a constitutive relation or an equation of state of the medium under consideration. Shock wave techniques provide a powerful tool for the investigation of equations of state at very high stress levels. The stress-volume behavior of frozen soil-water mixtures in the range from 60 to 500 kbar was investigated. Hugoniot data were obtained for Ottawa banding sand (pure quartz sand) and West Lebanon (New Hampshire) glacial till of varying degrees of saturation and for polycrystalline and monocrystalline ice (c-axis oriented in the direction of shock propagation). Release cross curve data were obtained for dry and saturated Ottawa banding sand and for polycrystalline ice. All materials were at an initial temperature of -10°C. In all experiments plane one-dimensional shock waves were used. The Hugoniots and release curves for the soil materials show evidence of a quartz-stishovite phase transition at about 300 kbar. The Hugoniots of single and polycrystalline ice do not differ significantly over the stress range studied - 30 kbar to 300 kbar.

Description / Table of Contents: CONTENTS: Preface. - Abstract. - Introduction. - Theory. - Application to ice sheets and ice shelves. - Summary. - Literature cited.

Description / Table of Contents: An analysis is made of the rate of bubble coalescence in a deforming ice mass. A total strain of at least 8 is required before appreciable coalescence occurs, The analysis has.been applied to deforming ice shelves and ice sheets. No appreciable coalescence is expected in ice shelves but coalescence should occur in ice sheets (or glaciers) if the shear strain rate at the bottom surface is of the order of 0.075/yr or larger. Measurements of bubble concentration are capable of setting limits on paleo-strain rates of the present ice sheets. Bubble migration down temperature gradients presents complications to the study of bubble coalescence.

Description / Table of Contents: CONTENTS: Abstract. - Preface. - Introduction. - Test locations. - Post Pond. - Mascoma Lake. - Winter freeze-up. - Ice cover properties. - Stratigraphy. - Microstructure. - Porosity. - Impurity content. - Flexural strength. - Test sites. - Beam test procedure. - Beam dimensions. - Beam temperatures. - Beam strengths. - Results. - Post Pond, Site PB, 12 February 1974. - Post Pond, Site PC, 21 February 1974. - Mascoma Lake, Site MD, 25 February 1974. - Mascoma Lake, Site MD, 26 February 1974. - Mascoma Lake, Site MD, 1 March 1974. - Post Pond, Site PA, 4 March 1974. - Post Pond, Site PA, 7 March 1974. - Post Pond, Site PA, 8 March 1974. - Post Pond, Site PB, 12 March 1974. - Post Pond, Midway between Sites PB and PC, 15 March 1974. - Post Pond, Midway between Sites PA and PB, 26 March 1974. - Post Pond, Midway between Sites PA and PB, 29 March 1974. - Post Pond, Midway between Sites PA and PB, 3 April 1974. - Conclusions. - Literature cited.

Description / Table of Contents: In-place cantilever beam tests on Post Pond and Mascoma Lake ice yielded a maximum flexural strength of 7.1 kg/cm^2. The minimum strength, unrelated to failure along pre-existing cracks in the ice, was 2.9 kg/cm^2. The majority of tests were performed in the push-down mode after it was discovered that beams tested in the pull-up mode, which places the bottom surface in tension, frequently broke prematurely along cracks in the bottom of the ice. Premature failures of this kind usually occurred at stresses of 2-3 kg/cm^2. Data further demonstrate that the intrinsic strength of lake ice decreases significantly as the surface air temperature goes to 0°C. Ice that has just become isothermal, but has not yet begun to candle, has a strength of about 4 kg/cm^2; ice that has been subjected to prolonged periods of above-freezing air temperatures generally fails at about 3 kg/cm^2. Tests also show that cold unrecrystallized snow-ice is as strong as the underlying lake ice. Tests of the effect of crystalline structure indicate that ice composed of crystals with their c-axes horizontal is measurably stronger than ice in which the crystals are oriented with their c-axes vertical.

Description / Table of Contents: CONTENTS: Preface. - Introduction. - Principle of the IR scanner. - Advantages of mobile infrared thermography. - Discussion of field measurements. - Recommendations for future work on thermography of buildings. - Other potential applications of infrared thermography of buildings. - Appendix A: Thermograms of northern exposure of USA CRREL building. - Appendix B: Sample thermograms of heat loss survey at Pease Air Force Base. -Appendix C: Sample thermograms of heat loss survey at Dartmouth College. - Abstract.

Description / Table of Contents: A method to assess quickly the insulation effectiveness of buildings using mobile infrared thermography has been developed at USA CRREL. In contrast to the infrared thermography done in Sweden, this method concentrates on obtaining useful data by measuring the outside surface temperature of structures. This report outlines the basic principles involved in these measurements, and discusses field measurements and the inherent advantages of infrared thermography. Typical thermograms are presented in the appendixes.

Description / Table of Contents: During the winter of 1973 - 74 a mobile infrared thermography system was used to survey the USA CRREL building at Hanover, New Hampshire. This report provides a description of excessive heat losses at several locations around the building. This report also discusses the need to carefully monitor meteorological conditions before starting a survey of a building exterior to determine if solar radiation decay from the building surface might interfere with thermographic analysis by masking the heat emanating from within the building.

Description / Table of Contents: CONTENTS: Preface. - Abstract. - Introduction and statermnt of problem. - Solution of problem shown in Figure 3. - Solution of problem shown in Figure 4. - The negligibility of the effects of buoyancy and incompressibility of the sealed liquid. - Literature cited.

Description / Table of Contents: After a brief description of the circumstances which led to the investigation of the title problem and discussion of some related previous investigations, exact solutions are derived for a circular plate which seals an incompressible liquid, is clamped along the boundary and is subjected at an arbitrary point to a lateral concentrated force P. For the case when the plate is covered by a thin liquid layer the solution is obtained in closed form. When this liquid layer is absent, the solution is obtained as an infinite series. The paper concludes with a study of the range of the parameter ([Lambda] a) for which the effort of buoyancy is negligible upon the deflections and stresses in the plate.

Description / Table of Contents: CONTENTS: Preface. - Abstract. - Introduction. - Previous work on unsteady rectilinear motion of a sphere. - Experiments with a circular path. - Conclusion. - Literature cited. - Appendix A: Comparisons of the measured and calculated forces.

Description / Table of Contents: Forces on a sphere moving unsteadily along a circular path in a viscous fluid are measured, and it is found that within the experimental range the formula valid for rectilinear motion has to be modified to account for the curvature of the path.

Description / Table of Contents: CONTENTS: Preface. - Abstract. - Introduction. - Theory. - Discussion. - Conclusion. - Literature cited.

Description / Table of Contents: A diffusion equation is obtained that describes the mechanical dispersion of a dilute mixture of solid particles within an ice matrix that is undergoing deformation. It is shown that within the limits of time intervals and strain rates appropriate to the movement of glaciers and ice sheets the dispersal distance usually is no larger than a distance about one order of magnitude greater than the size of the particles themselves.

Description / Table of Contents: Inhalt: 2. BAND: 1. ABTHEILUNG: POLARLICHT- UND SPECTRAL-BEOBACHTUNGEN, durchgeführt und bearbeitet von Linienschiffs-Lieutenant Adolf Bobrik von Boldva. - Einleitung. - Eintheilung des Beobachtungsmaterials. Beschreibung der aufgetretenen Formen und Definition der gebrauchten Ausdrücke. - Intensität des Lichtes. - Färbung der Polarlichterscheinungen. - Zugrichtung und Lichtbewegung. - Position und Höhe. Concentrationspunkt der Strahlen. - Polarlichter im Zusammenhange mit den magnetischen Störungen. - Abbildungen der Polarlichterscheinungen. - Polarlichter. - Tabellarische Zusammenstellungen. - Häufigkeit des Auftretens der verschiedenen Polarlichtformen in den einzelnen Richtungen ; Zugrichtung, Lichtbewegung und Intensität. - Höhe der Polarlichter über der Erdoberfläche ; Zusammenhang mit dem Wetter. - Die tägliche und jährliche Periode des Polarlichtes zu Jan Mayen. - Tabellen I-IX. - Spectralbeobachtungen und Farbe des Polarlichtes. - 2. ABTHEILUNG: MAGNETISCHE BEOBACHTUNGEN, bearbeitet von Linenschiffs-Lieutenant August Gratzl. - Einleitung. - Absolute Bestimmungen. - Declination. - Horizontal-Intensität. - Inclination. - Variationsapparate. - A. Die Wild-Edelmann'schen Apparate. - 1. Das Declinatorium. - 2. Das Bifilar-Magnetometer. - 3. Die Lloyd'sche Wage. - B. Die Lamont-Edelmann'schen Apparate. - 1. Das Unifilar. - 2. Das Unifilar mit Ablenkungsmagneten. - 3. Das Unifilar mit Eisenstäben. - Terminbeobachtungen. - Stündliche Beobachtungen. - Berechnung der Perioden. - Declination. - Horizontal-Intensität. - Vertical-Intensität. - Total-Intensität. - Inclination. - Störungen. - Normaltage. - Zusammenhang zwischen Polarlichtern und magnetischen Störungen. - Zusammenhang zwischen magnetischen Störungen und Sonnenflecken. - Gleichzeitige Änderung der verschiedenen Elemente bei Störungen. - Absolute Bestimmungen in der Umgegend der Station. - Schlusswort. - Tabellen. - Terminbeobachtungen: Termintage, Terminstunden. - Stündliche Beobachtungen der Declination. - Monatsstundenmittel der Declination. - Monatsstundenmittel der Inclination. - Monatsstundenmittel der Total-Intensität. - Stündliche Beobachtungen der Horizontal-Intensität. - Monatsstundenmittel der Horizontal-Intenstität. - Stündliche Beobachtungen der Vertical-Intensität. - Monatsstundenmittel der Vertical-Intensität. - Tagesmittel der Total-Intensität. - Tagesmittel der Inclination. - Zusammenstellung der Abweichungen der Declination. - Zusammenstellung der Abweichungen der Horizontal-Intensität. - Zusammenstellung der Abweichungen der Vertical-Intensität. - 3. BAND: Einleitung, von Dr. Ferndinand Fischer. - VI. THEIL: ZOOLOOGIE. - A. Foraminiferen, bearbeitet von Dr. Victor Uhlig. - B. Poriferen, Anthozoen, Ctenophoren und Würmer, bearbeitet von Dr. Emil von Marenzeller. - C. Polypomedusen, bearbeitet von Dr. Ludwig von Lorenz. - D. Echinodermen, bearbeitet von Dr. Ferdinand Fischer. - E. Crustaceen, Pycnogoniden und Arachnoiden, bearbeitet von Carl Koelbel. - F. Insecten, bearbeitet von Dr. Eduard Becher. - G. Mollusken, bearbeitet von Dr. Eduard Becher. - H. Bryozoen, bearbeitet von Dr. Ludwig von Lorenz. - I. Tunicaten, bearbeitet von Dr. Richard Freiherrn von Drasche. - K. Fische, bearbeitet von Dr. Franz Steindachner. - L. Vögel und Säugetiere, bearbeitet von Dr. F. Fischer und August von Pelzeln. - VII. THEIL: BOTANIK. - A. Flora der Insel Jan Mayen, bearbeitet von Dr. H. W. Reichardt. - B. Untersuchungen einiger Treibhölzer, ausgeführt von Josef Schneider. - VII. THEIL: MINERALOGIE. - Gesteine von Jan Mayen, bearbeitet von Dr. Fritz Berwerth.

Description / Table of Contents: The internal friction of single-crystal ice has been attributed to reorientation of the water molecule under periodic stress. However, the theory for damped dislocations, which offers another mechanism for the internal friction of ice, has not been investigated. The effects of scratching the surface of 41 ice samples and X-irradiating and plastically deforming them were evaluated. The effects observed on the internal friction of pure, single-crystal ice, in the flexure mode of oscillation between 400 and 1400 Hz, supported the existence of a dislocation-controlled mechanism, with the drag produced by the interaction of the dislocation with the protons in the crystal. In addition, analysis of the detailed shape of the data curve showed two peaks of tan delta as a function of temperature. The second peak, which had not been previously reported, had an activation energy of 0.16 eV and a relaxation time of 1.7 x 10^8 sec at infinite temperature. These experiments indicated that both peaks vrere controlled by the dislocation mechanism described above.

Description / Table of Contents: The attenuation of visible light by falling snow was studied by making simultaneous attenuation measurements and snow concentration measurements. The attenuation coefficient was calculated from photometric measurements and from visual observations. Snow concentration in the air was evaluated by two methods: from Formvar replicas collected during the snowfall, and by mass accumulation of snow in collecting pans. The snowflakes were arbitrarily classified by crystal types according to their estimated fall velocity. It was found that the correlation between extinction coefficient (attenuation) and snow concentration was generally much higher by types than when all snowflakes were considered together regardless of crystal components and degree of riming. Two types, apparently improperly classified, displayed lower correlations than the overall group. When no fog is present during the snowfall, the experimental results coincide well with attenuation theory if a reasonable correction is applied to the values obtained in the measurement of snowflake diameters. Measurements of mass flux indicate that for a given intensity the attenuation caused by snow is an order of magnitude greater than that caused by the same mass flux of rain.

Description / Table of Contents: CONTENTS: Preface. - Abstract. - Introduction. - Analytical procedures. - Results and discussion. - Bubbles in ice. - Conclusions. - Literature cited.

Description / Table of Contents: Application of the gas law to fourth-place density measurements of ice samples from two deep drill holes at Byrd Station and Little America V, Antarctica, shows that virtually all density increase beyond the pore close-off density (0.830 g/cm^3) can be attributed to compression of the entrapped bubbles of air. Data from Byrd Station also indicate that the lag between overburden pressure and bubble pressure, initially 4-5 kg/cm^2 at pore close-off, diminishes to less than 1.0 kg/cm^2 at about 200-m depth. By substituting the overburden pressure for the bubble pressure in the pressure-density relationship based on the gas law, ice densities below 200 m can be calculated more accurately than they can be measured per se on cores because of the relaxation that occurs in samples recovered from high confining pressures. This relaxation, resulting in a progressive increase in the bulk volume of the ice with time, is generally attributed to decompression of the entrapped air bubbles following removal of the ice from high confining pressures. However, calculations of the stress in ice due to bubble pressure, together with measurements of bubble sizes in cores from various depths at Byrd Station, both tend to indicate that there has'been negligible decompression of the inclosed bubbles. It is suggested that most of this relaxation may be due to the formation of microcracks in the ice. Anomalous bubble pressure-density relations at Little America V tend to confirm abundant stratigraphic evidence of the existence of considerable deformation in the upper part of the Ross Ice Shelf. Studies of crystal-bubble relations at Byrd Station revealed that the concentration of bubbles in ice remains remarkably constant at approximately 220 bubbles per cm^3. Bubbles and crystals were found to be present in approximately equal numbers at pore close-off at 64-m depth, at which level the average bubble diameter was 0.95 mm, decreasing to 0.49 mm at 116 m and to 0.33 mm at 279 m. Despite a tenfold increase in the size of crystals between 64 and 279 m, the bubbles showed no tendency to migrate to grain boundaries during recrystallization of the ice. The observation that most of the bubbles had assumed substantially spherical shapes by 120-m depth points to essentially hydrostatic conditions in the upper layers of the ice sheet at Byrd Station.

Description / Table of Contents: Inhalt: Vorbericht zur wissenschaftlichen Polarexpedition nach Jan Mayen von dem Leiter der Expedition Corvetten-Capitän Emil Edlen von Wohlgemuth. - 1. Theil Astronomie, bearbeitet von Linenschiffs-Lieutenant Richard Freiherrn Basso von Gödel-Lannoy. - 2. Theil Aufnahme und Beschreibung der Insel Jan Mayen und Beobachtungen über Gletscherbewegung, durchgeführt und bearbeitet von Linienschiffs-Lieutenant Adolf Bobrik von Boldva. - 3 Theil 1. Abtheilung Meteorologie, bearbeitet von Linienschiffs-Lieutenant Adolf Sobieczky. - 2. Abtheilung Temperatur und specifisches Gewicht des Seewassers, bearbeitet von J. Luksch und J. Wolf. - 3. Abtheilung Resultate der chemischen Untersuchungen über die von Jan Mayen mitgebrachten Seewasserproben, bearbeitet von A. Kliemetschek und J. Sobieczky. - 4. Abtheilung Ebbe- und Fluthbeobachtungen, bearbeitet von Linienschiffs-Lieutenant Adolf Bobrik von Boldva.

Description / Table of Contents: CONTENTS: Abstract. - Preface. - List of symbols. - Introduction. - Previous work. - Experimental design. - The radioisotope 22Na. - Description of apparatus. - Experimental procedure. - Correction of profiles. - Assumptions. - Decay correction. - Boundary correction. - Error analysis. - Results. - Salinity data. - Temperature data. - Growth velocity. - Discussion. - Brine and ice properties. - Brine salinity. - Brine density. - Brine volume. - Brine latent heat of freezing. - Brine viscosity, specific heat, and thermal conductivity. - Ice properties. - Theoretical brine expulsion model. - Continuity equations. - Thermal energy equation. - Simplified brine expulsion equations. - Brine expulsion in NaCl ice. - Results. - Discussion. - Gravity drainage in NaCl ice. - Application of results to natural sea ice. - Effective distribution coefficient. - Previous work. - Experimental procedure and results. - Conclusions. - Literature cited. - Appendix A: Profile correction data. - Appendix B: Program "correct" and sample output. - Appendix C: Tabulation of salinity data. - Appendix D: Tabulation of profile data. - Appendix E: Time-ice thickness equations (Runs 2 and 3). - Appendix F: Tabulation of distribution coefficient data.

Description / Table of Contents: To obtain a better understanding of the desalination of natural sea ice, an experimental technique was developed to measure sequential salinity profiles of a growing sodium chloride ice sheet. Using radioactive 22Na as a tracer, it was possible to determine both the concentration and movement of the brine within the ice without destroying the sample. A detailed temperature and growth history of the ice was also maintained so that the variation of the salinity profiles could be properly interpreted. Since the experimental salinity profile represented a smoothed, rather than a true salinity distribution, a deconvolution method was devised to restore the true salinity profile. This was achieved without any significant loss of end points. In all respects, the salinity profiles are similar to those of natural sea ice. They have a characteristic C-shape, and clearly exhibit the effects of brine drainage. Not knowing the rates of brine expulsion or gravity drainage, the variation of the salinity profiles during the period of ice growth could be explained by either process. To determine the relative importance of the desalination mechanisms, a theoretical brine expulsion model was derived and compared to the experimental data. As input for the model, equations describing the variation of some properties of NaCl brine with temperature were derived. These included the brine salinity, viscosity, specific heat, thermal conductivity, and latent heat of freezing. The theoretical brine expulsion model was derived by performing mass and energy balances over a control volume of NaCl ice. A simplified form of the model, when compared to the experimental results, indicated that brine expulsion was only important during the first several hours of ice growth, and later became a minor desalination process relative to gravity drainage which continued to be the dominant mechanism for the remainder of the study period (up to 6 weeks). The rate of gravity drainage was found to be dependent on the brine volume and the temperature gradient of the ice. As either the brine volume or temperature gradient was increased, the rate of change of salinity due to gravity drainage increased. The equation commonly used to calculate the effective distribution coefficient (Weeks and Lofgren 1967) was modified and improved by taking brine drainage into account. An expression was also derived to give the distribution coefficient at very low growth velocities.

Description / Table of Contents: CONTENTS: Abstract. - Preface. - USA CRREL project and personnel involvement. - Part I. Introduction. - Background. - Literature review. - Part II. CRREL investigations from 1970 - 1974. - Initial literature survey (1970). - Oil detection kit development. - Survey of Cape Simpson, Alaska, natural crude oil seepages (1970). - Haines-Fairbanks military pipeline investigations (1971-1973). - Barrow investigations (1970-1974). - Fairbanks and Fox investigations. - Germination studies. - Physiological studies. - Dispersant studies. - Microbiological investigations. - Field investigations of accidental petroleum losses. - Part III. Recent related literature. - Part IV. Conclusions and recommendations. - USA CRREL reports, publications and presentations on Alaska oil spill research. - Literature cited.

Description / Table of Contents: Knowledge concerning the biological effects of oil pollution on arctic and subarctic terrestrial ecosystems is limited. USA CRREL research personnel conducted investigations from 1970 through 1974 to expand information in this field. Objectives were to: 1) define the ecosystems most sensitive to the presence of crude oil or its refined products, 2) quantify and understand the injury response, and 3) establish time frames for manifestation of damage and natural restorative processes in arctic and subarctic regions. This was accomplished through: 1) surveys of natural oil seepages and past accidential spills in the Arctic and Subarctic, 2) initiation of controlled oil spills and 3) detailed laboratory investigations. Results demonstrated that terrestrial oil spills will to some degree be detrimental to both arctic and subarctic plant communities. Degree and longevity of damage will be influenced primarily by the magnitude of the spill, season of occurrence and existing soil moisture content. Rapid recovery of plant communities subjected to spills will occur only if root systems remain relatively unaffected. Damage will be more extensive and long-term when root systems are saturated with oil. Effects of damage will be manifested gradually over several seasons being influenced by winter stresses. Variation does exist in plant species susceptibility. Carex aquatilis, a predominant sedge of the arctic, is markedly resistant to crude oil damage. In the taiga Picea mariana is very susceptible. Plant recovery can be enhanced through the application of fertilizer. Fertilization, in addition to its direct effect on plant nutrition, will stimulate microbial decomposition of crude oil.

Description / Table of Contents: A 4-summer hydrologic record from a 1.6 km^2 drainage basin at Barrow, Alaska is analyzed. The watershed, a drained lake basin, is underlain by continuous permafrost within 0.3m of the tundra surface and is covered by ice-wedge polygons and numerous small shallow ponds. Considerable variations from the 20-yr means of summer climate (thaw period 88 days, precipitation 67 mm) are represented in the data: 1963 - cold, extremely wet; 1964 - cold, extremely dry; 1965 - cool, dry; 1966 - cool, wet. Runoff varied greatly from storm to storm, occurring primarily through and over the tundra mat and through an intricate system of polygonal troughs and ponds. As a result of the subdued coastal topography, varying areas (0.3 km^2 to 1.6 km^2) contribute to runoff from different storms. Analyses of hydrographs revealed: 1) lag times generally from 3 to 10 hr; 2) recession constants of about 50 hr, but occasionally as much as 160 hr; and 3) runoff from individual storms between 1 and 70%. About 5% of the thaw season precipitation normally runs off. Comparison of total thaw season precipitation between the U.S. Weather Bureau and a shielded gage located on the watershed indicated no major differences. If "trace" precipitation is considered, only 90% of the actual precipitation may be recorded. Pan evaporation for an average thaw season is about 160 mm and evapotranspiration which is essentially in balance with precipitation is about 60 mm. Conductivity of runoff water varied from 250 [My]mhos during sustained discharge to more than 500 [My]mhos during low flows in dry years. Precipitation chemistry showed no correlation with storm direction. Assuming all winter precipitation runs off, and the data are spatially and temporally representative, about 50% of the measured annual precipitation in this region runs off into the Arctic Ocean.

Description / Table of Contents: The flow of a compressible fluid through a deep layer of a porous medium with non-uniform permeability was analyzed. The volumetric behavior of the fluid was described first by the perfect gas law, then by the van der Waal's equation of state. Darcy's law was assumed to be valid. For illustration, the model of air flowing through a deep bed of naturally compacted snow was used to carry out numerical computation. The permeability of snow was considered as a function of depth. The nonlinear partial differential equation obtained by combining the continuity equation with Darcy's law was solved by finite difference technique. A time dependent exponential decay boundary condition was used which included the step-rise constant boundary condition as a limiting case. Pressure distributions in the porous medium calculated from the assumption of ideal gas and van der Waal's gas were compared. The data were presented in dimensionless variables.

Description / Table of Contents: CONTENTS: Preface. - Abstract. - Introduction. - Theoretical considerations. - Method of canopy evaluation. - Application to forest problems. - Forest blowdown. - Radioactivity gradient. - Phenology. - Forest types and structure. - Distribution of leaves and canopy gaps. - Light quality. - Discussion and summary. - Literature cited.

Description / Table of Contents: A technique for evaluating forest canopies was developed based on the use of a divergent lens system to obtain hemispherical photographs of tree crowns. The photography was processed from 35 mm film and enlarged as a silhouette, and the light transmission was measured with a specially fabricated macrodensitometer. It is concluded that the amount of forest canopy can be expressed as canopy closure index (CCI) at a precision of approximately 5%. It is shown by application to a variety of problems in diverse geographical areas that this technique can be used for measuring both temporal and spatial changes in the canopy, for estimating the shade light climate, and for specifying the probability of target detection through a canopy. Data are presented to analyze changes caused by explosions, radioactivity, growing season, and vegetation types. The geometry of gaps in tree crowns is discussed and the nature of shade light quality under forests is illustrated.

Description / Table of Contents: CONTENTS: Preface. - Introduction. - Previous work. - Study area. - Field procedures. - Results and discussion. - Conclusions. - Literature cited. - Abstract.

Description / Table of Contents: A modern ice-push ridge on the northwest shore of Gardner Lake in southeastern Connecticut is 0.6 - 1.2 m high and 1.2 - 3.1 m wide. In February and March 1967, the positions of survey stakes placed on the lake ice were measured periodically. During the same period, air and ice temperature and solar radiation intensity were also recorded. Analysis of the data supports the hypothesis that thermal expansion of the lake ice rather than wind action, was the principal cause of ice push. An ice temperature change of approximately 1°C/hr increase for 6 hr was sufficient to induce ice thrust. In a 30-day period, the average net shoreward movement of the surveyed area of the ice surface was 1.0 m. During the 1966-67 winter, approximately 14 m^3 of beach material was reworked and deposited, forming a discontinuous ice-push ridge along 260 m of shoreline.

Description / Table of Contents: CONTENTS: Introduction. - Summer temperature data. - Station network and history. - Parameters for data reduction. - Analysis of summer temperatures. - Temperature trends. - Summer temperatures in the highlands. - Lapse rates for summer temperatures. - Spatial variation of summer temperatures. - Summary. - Literature cited. - Appendix A. - Appendix B. - Appendix C. - Abstract.

Description / Table of Contents: Annual degree-day summations over bases of 43°F and 50°F in 15-day periods from May through August are given for the period of record for five interior Alaska climatic stations. Average temperature and precipitation data are included. Patterns of summer temperature in interior Alaska are analyzed in terms of historical, elevational and areal differences. Since 1900, summer temperatures show little long-term change but significant short-term changes. In contrast, winter temperatures show considerable fluctuations, which are reflected in mean annual temperatures to a much greater degree than are summer temperature fluctuations. Average summer lapse rates for the 1600 to 3300 and 3300 to 6600-ft levels were 3.4 and 3.7°F/1000 ft, respectively, based on timberline temperature observations and on upper air data from Fairbanks. Correlation analysis of daily and monthly average July temperatures indicates areas of uniformity with respect to temperature variation. This provides information on lowland climatic stations that are representative of highland locations, especially the Yukon-Tanana Uplands

Description / Table of Contents: Content: Aurores boreales / par Carlheim-Gyllenskiöld. - Électricité atmosphérique / par S. A. Andrée. - Phénomènes optiques de l'atmosphère, avec quelques remarques sur les Étoiles filantes, le spectre des Copépodes, l'accroissement des brins d'orge / par Carlheim-Gyllenskiöld. - Recherches sur le prétendu changement de la couleur de la peau après un hivernage dans les régions polaires / exécutées par R. Gyllencreutz, communiquées par Frithiof Holmgren.

Description / Table of Contents: CONTENTS: Abstract. - Preface. - Introduction. - Experimental. - Results and discussion. - Applications. - Literature cited.

Description / Table of Contents: Chemical analysis of century-old ice from continuous 5 to 7 year intervals of three ice cores from south and central Greenland (Dye 3, Milcent and Crete) show maximum concentrations of Na, Mg,Ca, K, and Al during early spring and minimum concentrations during late summer and early fall. Peak spring values are as much as 10 times greater than fall values. Because of the large seasonal chemical variations, samples used for depth-age or annual deposition rate studies must represent accumulation from exactly one year or whole multiples of a year. The seasonal chemical variations seem promising as a new method of defining annual layers and thus dating old ice cores.

Description / Table of Contents: Table des matières: TOME 1 MÉTÉOROLOGIE. - Introduction. - Observation météorologique. - Pression atmosphérique. - Température de l'air. - Température sur le sol. - Température du sol: 1° à 0,4 m., 2° à 0,8 m. et 3° à 1,6 m. de profondeur. - Humidité de l'air. - Direction et vitesse du vent. - Nébulosité, forme et direction des nuages, hydrométéores. Eau tombée. - Evaporation de l'eau douce. - Température sur le sol et à 6 cm. de profondeur. - Température de l'eau de la rivière. - Remarque diverses; couches des nuages à hauteur différente. - Observations météorologiques de l'année 1883-84 faites à Sodankylä. - Remarques diverses 1883-84. - Observations météorologiques faites à Kultala. - Remarques diverses. - Aperçu général de moyennes mensuelles et de variations diurnes: variation de la pression atmosphérique, de la température de l'air, de la température sur le sol, de l'humidité de l'air, de la vitesse du vent, de la nébulosité et de l'eau tombée. - Fréquence des vents. - Les années 1882 - 83 et 1883 - 84 au point de vue météorologique. - TOME 2 MAGNÉTISME TERRESTRE. - Déterminations magnétiques absolues. - Observations des variations magnétiques. - Réduction des observations en valeurs absolues. - Déterminations des constants pour les instruments de variation à Kultala. - Déterminations magnétiques absolues faites à quelques endroits pendant le voyage. - Remarques sur les tableaux. - Observations mangnétiques 1882-1883. - Déclinaison. - Intensité horizontale. - Intensité verticale. - Observations-termes magnétiques 1882-1883. - Variations des éléments magnétiques pendant les jours termes. - Observations faites de 20 secondes en 20 sec. pendant les jours termes. - Observations magnétiques 1883-1884. - Observations horaires des éléments magnétiques à 5h a. m., 1h p. m. et 9h p. m. temps moyen de Göttingue. - Observations-termes magnétiques 1883-1884. - Variations des éléments magnétiques pendant les jours termes. - Variations des éléments magnétiques observées chaque demi-minute de 8h 30m à 10h 30m p. m. le 1er, 8me, 15me et 22me du chaque mois. - Variations des éléments magnétiques observées chaque demi-minute pendant une heure au soir avant les jour-termes suivantes: 1 janvier de 6h à 7h p.m., 14 janvier 7h-8h p. m., 31 janvier 8h-9h p. m., 14 février 9h-10h p. m., 29 février 10h-11h p. m. et 14 mars 11h-12h p. m. - Perturbations magnétiques observées. - Observations magnétique faites à Kultala. - Tableaux des variations magnétiques diurnes observées pendant les jours sans perturbations, conformément au projet de M. Wild. - Planches. - 1. Courbes représentant les moyennes des variations magnétiques diurnes pendant les jours sans perturbations, conformément au projet de M. Wild. - 2. Suite de courbes précédentes et courbes représentant les moyennes des moyennes précédentes.

Description / Table of Contents: This paper considers a load moving with a constant velocity across an ice sheet that is floating on water. The ice sheet is assumed to be an isotropic, elastic, thin plate extending to infinity. The water is assumed to be inviscous, incompressible, and of a constant depth. The dynamic equations describing this ice-water system are solved for the steady state solution. Both a concentrated load and a uniform load distributed over a circular area are considered. The velocity which causes resonance is determined. The deflection and stress directly under the load are numerically evaluated.

Description / Table of Contents: CONTENTS: Preface. - Abstract. - Introduction. - Analytical procedures. - Results and discussion. - Literature cited.

Description / Table of Contents: Conductivity measurements have been made on snow and ice samples from pits and deep drillholes at a number of localities in Antarctica and Greenland. Conductivities of the order 1-2 [My]mho/cm only were recorded at the inland sites. Data from deep cores representing more than 1900 years of continuous snow accumulation at Byrd Station, Antarctica, and more than 400 years deposition at Inge Lehmann, Greenland, showed no significant variations of conductivity with time. Measurements of freshly precipitated snow from a single coastal location in McMurdo Sound, Antarctica, also yielded relatively low conductivities of the order 3-4 [My]mho/cm. The substantial increase observed in the conductivity of core samples from near the surface of the Ross Ice Shelf at Little America V can be attributed most probably to windborne salts of marine origin that had accumulated on the surface after the snow was deposited. A peak conductivity of 49 [My]mho/cm was recorded in snow estimated to have been deposited within 20 km of the seaward edge of the Ross Ice Shelf and the maritime effect could still be detected in samples deposited more than 40 km from the ice front. For samples deposited at distances of greater than 200 km from the edge of the Ross Ice Shelf conductivities never exceeded 2 [My]mho/cm. The very low conductivities observed in ice cores from near the bottom of the Ross Ice Shelf confirm earlier conclusions based on detailed petrographic studies oi the cores that the 258-m-thick ice shelf at Little America V is composed entirely of glacial ice.

Description / Table of Contents: CONTENTS: Preface. - Abstract. - Introduction. - Snow crystals in Greenland. - Microspherules. - Microspherules in snow and ice-fog crystals. - Concentration and radii of spherules. - Discussion and conclusions. - Literature cited.

Description / Table of Contents: Spherules found in snow crystals, ice-fog crystals, fallout particles, and fly ash were studied with an electron microscope using the electron diffraction method. The central part of the residues of 1004 specimens of natural snow crystals from Greenland, the United States, and Japan were examined; 14 spherules 0.1 to 1.5? in radius were found among them. The residues of 658 artificial ice-fog crystals formed from water vapor in flue gases of coal-burning electric power plants at Fairbanks, Alaska, were also examined; nine spherules were found. Spherules similar to those found in ice-fog residues were found in furnace-produced fly ash fallout at Fairbanks, Alaska. Electron and optical microscope examination of spherules found in Greenland snow reveals a size distribution of the form dN/d(log r) = Cr-ß where ß approximately 3. The properties of spherules and the mean mass of snow crystals from Greenland are described. The electron microscope study indicated that less than 0.7% of the 1004 snow crystals contained spherules of possible extraterrestrial origin, and that snow crystals are formed mainly on clay mineral particles by heterogeneous nucleation.

Description / Table of Contents: CONTENTS: Introduction. - Methods. - Results. - Ground and aerial photography. - Hemispherical photography. - Light quality. - Discussion. - Literature cited. - Abstract.

Description / Table of Contents: Aerial and ground photographs were taken over a 2-year period of sites in the El Verde rain forest to record the consistency of the vegetational patterns in untreated sites and the changes that occurred following gamma irradiation. Four emulsions were used: panchromatic infrared, false color transparency and color transparency. Densitometry was used to evaluate color film and the vegetation response to 3 months of radiation. The color emulsions provided the sharpest indication of damage to vegetation and the succession following treatment. Hemispherical photography of the canopy was evaluated in terms of a canopy cover index defined as percent of light passing through the negative in a 90-degree cone area. Control stations were remarkably constant in all photography, establishing the stability and slow natural changes in rain forest structure. Spectral light measurements within the forest confirmed the predominance of far red shade light. Compared to similar studies on the chronic irradiated forest at Brookhaven National Laboratory the El Verde results were less distinct.