Examination of Sea Ice Cover in Norwegian Fjords

Presented are two steps being taken to examine sea ice coverage in Norwegian fjords as part of a larger study to improve our understanding of ice formation and breakup processes in these regions and implications for oil spill response. First, working with Google Earth Engine, MODIS images will be analyzed to determine where and when seasonal ice formation occurred along the Norwegian coastline since 2000. Here we summarize a simple method developed to quantify ice area in these regions to examine trends through the ice season and between years. While the larger study will cover a number of fjords, as an example focus is placed on Efjord, located in Nordland county, which has experienced large variations in ice coverage between years. We discuss the use of other datasets to determine the causes of such fluctuations focusing on the close relationship between run-off and ice cover in Efjord. Second, measurements of water temperature and salinity and ice thickness, stratigraphy, and salinity will be gathered over a three year period to better understand the ice observed in the MODIS images. The first set of measurements collected in November 2017 before freeze up are discussed below. In addition, initial images collected from time lapse cameras positioned to observe general weather and ocean conditions and the initial freeze up of ice are presented.submittedVersio

Laboratory In-situ Burns of Oil on Ice

Oil spills in ice-covered waters pose unique challenges to remediation activities. In-situ burning is a potential remediation technique that has shown promising efficiency in earlier trials. An element of arctic in-situ burning is the feedback between the flame of a burn on oil-infiltrated sea ice and the melting ice beneath. A series of experiments was devised to quantify the impact of this mechanism on burn efficiency. Seven experiments were performed that started with a crude oil pool of 0.2 or 0.3 m diameter on a 1 x 1 m2 freshwater ice block. The pools were ignited and the development of the flame, ice temperatures, and ablation rates was monitored. All burns ended in a vigorous burn phase (boil-over). Burn efficiency was below 65 %. A simple pond spread model was used to derive burn rates of a spreading pond. Burn rates were mostly around 0.9 mm/min. The low burn efficiencies were found to result from significant increase of the pond area during the burn in combination with relatively thin initial oil pools. The measurements provide a starting point to address the feedback effect of pond spread and ablation on burns on an oil-infested sea ice surface layer.Laboratory In-situ Burns of Oil on IceacceptedVersio

X-ray dark-field radiography for in situ gout diagnosis by means of an ex vivo animal study

Gout is the most common form of inflammatory arthritis, caused by the deposition of monosodium urate (MSU) crystals in peripheral joints and tissue. Detection of MSU crystals is essential for definitive diagnosis, however the gold standard is an invasive process which is rarely utilized. In fact, most patients are diagnosed or even misdiagnosed based on manifested clinical signs, as indicated by the unchanged premature mortality among gout patients over the past decade, although effective treatment is now available. An alternative, non-invasive approach for the detection of MSU crystals is X-ray dark-field radiography. In our work, we demonstrate that dark-field X-ray radiography can detect naturally developed gout in animals with high diagnostic sensitivity and specificity based on the in situ measurement of MSU crystals. With the results of this study as a potential basis for further research, we believe that X-ray dark-field radiography has the potential to substantially improve gout diagnostics

An overview of trends and regional distribution of thermal ice loads on dams in Norway

Norway has over 3000 dams, over half of which are concrete dams [1]. Static ice loads are considered as part of dam design and during period safety review. They present a significant fraction of the total design load of low dams, also called small dams, common in Norway [1]. Ice loads are traditionally considered driven by the thermal expansion of ice, although measurements showed that slow water level fluctuations covering a range similar to ice thickness have the potential to cause loads of similar magnitude [2]. Commonly used static ice loads in dam design include 100 to 150 kN/m in Norway, regionally-dependent 50 to 200 kN/m in Sweden, ice thickness-dependent 150 to 220 kN/m in Canada, and at least up to 300 kN/m in Russia [3]. While the climate in Norway ranges from temperate to polar, no specific rules are in place to help select design ice loads based on regional differences. Instead, climatic conditions may be considered on a case-by-case basis. To-date, no global failures of dams due to ice loads have been reported in Norway [1], raising the question whether current design practices are too conservative.An overview of trends and regional distribution of thermal ice loads on dams in NorwayacceptedVersio

MOSIDEO/CIRFA Experiments on Behavior and Detection of Oil in Ice

- Preparedness and response to oil in sea ice-covered waters - When does oil melt out of the ice - When can oil be detected with remote sensing techniques?submittedVersio

The anisotropic scattering coefficient of sea ice

Radiative transfer in sea ice is subject to anisotropic, multiple scattering. The impact of anisotropy on the light field under sea ice was found to be substantial and has been quantified. In this study, a large data set of irradiance and radiance measurements under sea ice has been acquired with a Remotely Operated Vehicle (ROV) in the central Arctic. Measurements are interpreted in the context of numerical radiative transfer calculations, laboratory experiments, and microstructure analysis. The ratio of synchronous measurements of transmitted irradiance to radiance shows a clear deviation from an isotropic under-ice light field. We find that the angular radiance distribution under sea ice is more downward directed than expected for an isotropic light field. This effect can be attributed to the anisotropic scattering coefficient within sea ice. Assuming an isotropic radiance distribution under sea ice leads to significant errors in light-field modeling and the interpretation of radiation measurements. Quantification of the light field geometry is crucial for correct conversion of radiance data acquired by Autonomous Underwater Vehicles (AUVs) and ROVs

Morphologies of ridges surveyed off Svalbard and in Fram strait, 2011 and 2012 field expeditions

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Porosity of growing sea ice and potential for oil entrainment

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Hydrogeologic conditions in the Boise Front geothermal aquifer Appendix H: Measuring point locations for geothermal monitoring wells. Research report 2003-05

Appendix H uses full color photos to document the exact measurement points on geothermal monitoring wells used in the report: Hydrologic conditions in Boise Front geothermal aquifer (Petrich 2003), including measurements and arrows to identify the points

Winter concreting full-scale field trial of rock tower foundations

Winter concreting can be an attractive option for construction in remote areas where concerns about wildlife and soil integrity are prioritized. In order to minimize disturbance of wildlife and to be able to access remote sites with minimal damage to the soil, partial winter construction of a power line is being considered in northern Norway. Ice formation has to be prevented during the early stages of concreting of mast foundations in order to ensure design properties, long transportation ways have to be considered, and quick setting and achievement of the ultimate design strength are desired. Conventional materials in conjunction with artificial heating are considered to provide a potential solution. In the current field trial we investigated the feasibility of grouting anchor bolts (rock anchors) at ground temperatures below freezing using a vertically-installed hydronic heating system to warm up the rock prior to grouting. Also, hydronic heating of the footing during winter concreting has been tested. We found that the method is able to maintain temperatures well above freezing.Winter concreting full-scale field trial of rock tower foundationssubmittedVersio