The basal ice of temperate-type glacier Nigardsbreen is described in terms of a sediment facies model-after Lawson (1979). The ice is characterised using data obtained from sedimentological, chemical and stable isotopic analyses. These indicate that ice nearest the glacier bed is distinguishable from the ice above descriptively and genetically. In particular, the measurement of paired Oxygen and Hydrogen isotope contents, in accordance with theory proposed by Jouzel and Souchez (1982), provides a means of separating the basal facies ice component, formed by subglacial/basal regelation processes, from ice formed by 'normal' non-fractionating firnification processes. In the latter case the basic isotope content is close to that of the original precipitation whilst in the former this precipitation (meteoric) relationship is modified when ice is subjected to more or less predictable levels of fractionation during regelation. Some 1-1.5m of the basal ice, both early and late in the melt season, was found to originate from regelation. Within the basal facies ice, both stratified debris-laden layers comprising fine gravel-dominated debris up to concentrations of 1kg/l (c30% by volume) and clear intercalated ice types, reflect the regelation processes involved in debris entrainment and the freezing on of water. Thick (up to 40cm) layers of clean macrocrystalline 'regelation1 ice are considered to have been recrystallised. Coisotopic analysis may be used to highlight the fact that mixing of waters of differing origins occurs at the ice-bed interface and that the prediction of the extent of refreezing proposed by Jouzel and Souchez appears untenable. Major cation chemical analysis, undertaken to obtain data for use in the Souchez and Tison (1981) model of basal ice formational processes, which purports to discriminate between ice formed from water squeezed through the basal ice and water flowing, or ponded, at the bed, proved inconclusive. It appears that considerable desorption from clay minerals occurs and that squeezing of basal waters through the stratified facies may occur. In the absence of a clear statement of mineralogical composition in the basal debris clay fraction, which was attempted at Nigardsbreen, the Souchez and Tison model is seen to require development before it will reveal new information about basal processes. Measurements of temperature, sliding velocity and strain within subglacial cavities, in conjunction with observations on changes in sedimentological and isotopic conditions throughout the basal facies zone, are used to test and vindicate a descriptive model of the character, origin and evolution of the basal ice. The model is in turn proposed for further test.

This thesis reports on my Ph.D. research in the area of microwave remote sensing of the Arctic. The main objective of this research is to reconstruct the dielectric profile of the snow-covered sea ice, and indirectly retrieve some of its geophysical and thermodynamic properties. To meet this objective, a nonlinear electromagnetic inverse scattering algorithm is developed that consists of forward and inverse solvers. The input to this algorithm is the normalized radar cross section (NRCS) data collected by radar systems from the snow-covered sea ice profile. The proposed inversion algorithm iteratively minimizes a discrepancy between the measured and simulated NRCS data to achieve an accurate reconstruction. Two main challenges associated with this inverse problem are its ill-posedness and its limited available scattering data. To tackle these, the utilization of appropriate regularization and weighting schemes as well as the incorporation of prior information into the inversion algorithm are employed. These include the utilization of (i) appropriate weighting factors for the misfit cost function, (ii) more sensitive NRCS data with respect to the unknown parameters, (iii) further parametrization of the profile based on the expected distribution, (iv) time-series NRCS data to better initialize the inversion process, and (v) NRCS data collected by the satellite and on-site scatterometer to be inverted simultaneously for profile reconstruction. The experimental data utilized are collected by the author in collaboration with the Centre for Earth Observation Science. These measurements are performed on (i) the artificially-grown sea ice in the Sea-ice Environmental Research Facility, located at the University of Manitoba during winter 2014, and (ii) the landfast sea ice located in the Arctic (Cambridge Bay, Nunavut) during May 2014. The measurement procedure includes NRCS data collection through an on-site C-band scatterometer and a spaceborne SAR satellite and physical sampling of the snow and sea ice. The proposed electromagnetic inverse scattering algorithm is utilized to invert these experimental data sets, as well as some synthetic data sets. It will be shown that the use of various techniques developed in this thesis in conjunction with the developed inversion algorithm results in reasonable snow-covered sea ice profile reconstruction. / October 2016

Uppsatsen är en genushistorisk undersökning av tre filmer från olika decennier. Syftet med uppsatsen är att utreda hur filmer från Walt Disney Animation Studios framställer manligt och kvinnlig genus, samt i vilken mån filmerna speglar den tid de producerades. Metoden är en textanalys av tre filmer. De filmer som analyseras, baserat på specifika urvalskriterier, är Snow White and the Seven Dwarfes (1937), The Rescuers (1977) och Aladdin (1992). Textanalysen uppmärksammar vilka egenskaper som ges till respektive karaktär. De uppmärksammade egenskaperna delas upp i två kategorier: inre och yttre attribut. Med inre attribut avses karaktärernas personlighet och dialog. Yttre attribut avser konkreta ageranden samt det som är möjligt att se med blotta ögat. Undersökningen finner att framställningen av manligt och kvinnligt genus har förändrats över tid. Det blir lättare för karaktärerna att tillskriva sig egenskaper som traditionellt sett tillhört det andra genusets. Analysen av filmerna visar att de i många avseenden är avspeglingar av den tid de producerades. Vidare är det tydligt att karaktärernas inre attribut är mer stabila över tid, medan karaktärernas yttre attribut varierar mer över tid. Detta uppfattas som att det i filmerna finns en orubblig kärna i de inre attributen. Denna kärna ges dock olika uttryck i de yttre attributen.

Previous work demonstrates conflicting evidence regarding the influence of snowmelt timing on forest net ecosystem exchange (NEE). Based on 15years of eddy covariance measurements in Colorado, years with earlier snowmelt exhibited less net carbon uptake during the snow ablation period, which is a period of high potential for productivity. Earlier snowmelt aligned with colder periods of the seasonal air temperature cycle relative to later snowmelt. We found that the colder ablation-period air temperatures during these early snowmelt years lead to reduced rates of daily NEE. Hence, earlier snowmelt associated with climate warming, counterintuitively, leads to colder atmospheric temperatures during the snow ablation period and concomitantly reduced rates of net carbon uptake. Using a multilinear-regression (R-2=0.79, P<0.001) relating snow ablation period mean air temperature and peak snow water equivalent (SWE) to ablation-period NEE, we predict that earlier snowmelt and decreased SWE may cause a 45% reduction in midcentury ablation-period net carbon uptake.

Accurate precipitation-type forecasts are essential in many areas of our modern society andtherefore there is a need to develop proper working methods for this purpose. Focus of thiswork has been to study important physical processes decisive in deciding both the temperatureof the precipitation particles, hence affecting their phase, and the surrounding air. Two majorlatent heating effects have been emphasized, melting effect and cooling byevaporation/sublimation. Melting of the snow flakes subtracts heat from the surroundings andhence acts as a cooling agent. Phase transformation from solid/liquid into the gas phase alsoneeds heat which here results in a cooling tendency. These two mechanisms may sometimeshave a crucial influence for deciding the correct precipitation-type. The melting effect isdiscussed in a paper about a snow event in Tennessee in USA, and another paper describingan event in Japan showing the influence of the evaporation/sublimation process. In the lattercase the wet-bulb temperature, Tiw as a physical correct discriminator between snow and rainis obtained. A numerical weather prediction model (HIRLAM) is being used to study differentcondensation schemes during three weather situations occurring in Sweden. These areRasch/Kristjánsson condensation scheme, Sundqvist original condensation scheme and amodification of the latter scheme. In the modified Sundqvist condensation scheme the Tiw hasbeen implemented as a limit temperature between snow and rain. The results are showingdifferences between the two main schemes concerning the total precipitation (both snow andrain). Comparisons between Sundqvist condensation scheme and this modified version, calledSundqvist scheme with Tiw show that this latter version creates slightly more snow.Differences between them are largest in dryer areas. Differences in the snow accumulationincrease when the forecast length increases. That makes them harder to be compared to snowanalyses from MESAN (mesoscale analysis) because the analyses is partly based ondifferences in the snow depth and this cannot be directly compared to amount of newly fallensnow especially when surface air temperatures are above freezing. Deviations from the dataanalyses are obtained in both Sundqvist and Sundqvist scheme with Tiw but in some regionsthe latter is in better agreement with measurements. Further work is needed in precipitationtypestudies but the physical correct value with Tiw = 0 ºC as melting temperature used inSundqvist with Tiw scheme is an interesting project for the future in the field of precipitationtypeforecasting. / Sammanfattning av ”Regn eller snö? En fråga om våta temperaturen” Noggranna prognoser beträffande nederbördstyp är väldigt viktiga inom många områden isamhället. Det finns därför ett behov att utveckla bra metoder att avgöra om nederbördenfaller som regn eller snö. Viktiga fysikaliska processer är avgörande för nederbördens och denomgivande luftens temperatur; processernas kritiska betydelse för dess fas har satts i fokus.De två största latenta värmeeffekterna, avkylning genom smältning och genomavdunstning/sublimation har betonats. Smältning av snöflingorna extraherar värme frånomgivningen och därmed sänks temperaturen. Avdunstning och sublimation erfordrar värmeför fastransformation vilket även här tas från omgivningen och därmed en kylande effekt somföljd. Dessa två latenta värmeeffekter har ibland kritisk betydelse för nederbördstypen vidmarkytan och detta diskuteras dels i en artikel om en vädersituation från Tennessee (Kain etal., 2000) där smälteffekten fick avgörande betydelse för nederbördsfasen vid markytan, dels istudier från Japan där betydelsen av avdunstning och sublimation på nederbördstypenbetonats (Matsuo and Sasyo, 1981). I det senare fallet tydliggörs isobara våta temperaturenoch dess betydelse som diskriminator mellan regn och snö. En numerisk vädermodell (HIRLAM) har använts för att studera olika typer avkondensationsscheman och deras betydelse för nederbörden under tre olika väderskeenden iSverige. Dessa är Rasch/Kristjánssons kondensationsschema, Sundqvistskondensationsschema samt en något ändrad variant av Sundqvists kondensationsschema dären subrutin för beräknandet av Tiw har implementerats och ersatt den vanliga temperaturen iden del av schemat som beräknar smältning av nederbörd i fast form. Smälttemperaturen harsedan satts till 0ºC. Resultatet visar skillnader mellan Rasch/Kristjánssons schema ochSundqvists schema beträffande total 12 timmars nederbörd (regn och snö). Vissa periodertenderar Sundqvists kondensationsschema att överproducera nederbörden medan under andraperioder är det Rasch/Kristjánssons schema, som överproducerar jämfört mednederbördsobservationer. Jämförelser mellan Sundqvists schema och Sundqvists schema medTiw visar att den senare producerar mer ackumulerad snömängd med de största skillnaderna iområden som avviker mest från mättnad (100 %). Där finner vi också större differensermellan den vanliga temperaturen och Tiw. Skillnaden blir större när vi ökar den totala tiden förackumulerad snömängd men dessa värden blir då också svårare att verifiera med snöanalyserfrån MESAN. Detta då snöanalyserna bygger på skillnader mellan aktuell och föregåendeobserverade snödjup. Detta behöver ej alls vara lika med den verkliga mängden nysnö somfallit, speciellt under mätperioder då det är plusgrader. Avvikelser från snöanalyserna kannoteras i både Sundqvists schema och Sundqvists schema med Tiw. I vissa regioner är docksnöprognosen från den senare något bättre. Det fysikaliskt korrekta värdet av Tiw = 0ºC somsmältgräns mellan regn och snö istället för den vanliga temperaturen, utgör grunden förintressanta framtida studier beträffande nederbörd och nederbördstyp.

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Master thesis is concerned with the subject of a snow cover dynamics (focused on snow melting) and of the detailed analysis of each physical-geographic factors effect on its character. Knowledges published in the domestic and foreign scientific literature are confronted with the data acquired within a number of expeditionary snow monitoring campaignes carried out during winter periods 2011/2012 a 2012/2013 in headwaters of rivers of Šumava (Šumava Mts., southwestern Czechia). Mobile field survey was done in a number of time horizons within the broadly conceived research in the upper Otava River basin concentrated on the assessment of the retention potential in headstream areas.

Title: Application of the Snowmelt Runoff Model for snow accumulation and snowmelt modelling in experimental catchments Bystřice and Zlatý Brook in the Krušné Mountains Modelling of hydrological processes is a dynamically developing part of hydrology. The Snowmelt Runoff Model (SRM) was applied for modelling the runoff in two experimental catchments Bystřice and Zlatý Brook. The aim of this thesis is to set up and calibrate SRM model and to evaluate methods and procedures used for runoff simulations. The SRM model was used for modelling snow accumulation and snowmelt in two selected catchments in the Krušné Mountains. The snow depths and snow water equivalents are measured since 2009 at selected locations situated in catchments. Calibration and validation of the model was based on continual time series of precipitation, air temperature and discharge measured 2009. Hydrological years 2009 and 2010 were used for model calibration and hydrological years 2011 and 2012 were used for model validation. Sensitivity analysis, which quantifies the effect of individual model parameters on the simulating proces, was carried out based on results. Recession coefficient and runoff coefficient belong to the most sensitive parameters with highest impact on runoff simulations. Model calibration was successful, which...

The Red Scare of the late 1940s and 1950s was fueled by claims of governmental espionage from former members of the communist underground. Harry Dexter White, Assistant Secretary of the Treasury was accused of being a Soviet agent of influence. This paper will analyze the current issues in the discussion of Soviet espionage and focus on White's activities in this regard. The evidence on White is clear enough to show that he did pass sensitive information to the Soviets. He also succeeded in subverting American policy to favor Soviet interests over U.S. interests. White's activities in government service suggest that American government officials passed on vital government information to the Soviet Union and subversive activity went on in the U.S. in the 1930s and 1940s.

Approved for public release; distribution is unlimited. / An established cloud analysis routine has been modified for use in the Arctic. The separation of clouds from the snow and sea ice backgrounds is accomplished through a multispectral technique which utilizes VHRR channel 2 (visible), channel 3 (near infrared) and channel 4 (infrared) data. The primary means of cloud identification is based on a derived channel 3 reflectance image. At this wavelength, a significant contrast exists between liquid clouds and the arctic backgrounds, unlike in the standard visible and infrared images. The channel 3 reflectance is obtained by first using the channel 4 emission temperature to estimate the thermal emission component of the total channel 3 radiance. This thermal emission component is subsequently removed from the total radiance, leaving only the solar reflectance component available for analysis. Since many ice clouds do not exhibit a substantially greater reflectance is channel 3, the routine exploits differences in transmissive characteristics between channels 3 and 4 for identification. The routine was applied to six case studies which had been analyzed by three independent experts to establish 'ground truth'. Verification of the cloud analysis results, through a comparison to the subjective analyses, yielded impressive statistics. A success rate of 77.9% was obtained with an arguably small data base of 131 undisputed scenes / http://archive.org/details/objectivetechniq00barr / Lieutenant, United States Navy