In recent years, concern has grown over the consequences of global warming. The arctic region is thought to be particularly vulnerable to increasing temperatures, and warming is occurring here substantially more rapidly than at lower latitudes. Consequently, assessments of the state of the Arctic are a focus of international efforts. For the terrestrial Arctic, large datasets are generated by remote sensing of above-ground variables, with an emphasis on vegetation properties, and, by association, carbon fluxes. However, the terrestrial component of the carbon (C) cycle remains poorly quantified and the below-ground distribution and stocks of soil C can not be quantified directly by remote sensing. Large areas of the Arctic are also difficult to access, limiting field surveys. The scientific community does know, however, that this region stores a massive proportion (although poorly quantified, soil C stocks for tundra soils vary from 96 to 192 Gt C) of the global reservoir of soil carbon, much of it in permafrost (900 Gt C), and these stocks may be very vulnerable to increased rates of decomposition due to rising temperatures. The consequences of this could be increasing source strength of the radiatively forcing gases carbon dioxide (CO2) and methane (CH4). The principal objective of this project is to provide a critical evaluation of methods used to link soil C stocks and fluxes at the usual scales spanned by the field surveys (centimetre to kilometre) and remote sensing surveys (kilometre to hundreds of kilometres). The soil C distribution of two sub-arctic sites in contrasting climatic, landscape/geomorphologic and vegetation settings has been described and analysed. The transition between birch forest and tundra heath in the Abisko (Swedish Lapland) field site, and the transition between mire and birch forest in the Kevo (Finnish Lapland) field site span several vegetation categories and landscape contexts. The natural variability of below-ground C stocks (excluding coarse roots > 2 mm diameter), at scales from the centimetre to the kilometre scale, is high: 0.01 to 18.8 kg C m-2 for the 0 - 4 cm depth in a 2.5 km2 area of Abisko. The depths of the soil profiles and the soil C stocks are not directly linked to either vegetation categories or Leaf Area Index (LAI), thus vegetation properties are not a straightforward proxy for soil C distribution. When mapping soil or vegetation categories over large areas, it is usually necessary to aggregate several vegetation or soil categories to simplify the output (both for mapping and for modelling). Using this approach, an average value of 2.3 kg C m-2 was derived both for soils beneath treeless areas and forest understorey. This aggregated value is potentially misleading, however, because there is significant skew resulting from the inclusion of exposed ridges (with very low soil C stocks) in the ‘treeless’ category. Furthermore, if birch trees colonise tundra heath and other ‘open’ plant communities in the coming decades, there will likely be substantial shifts in soil C stocks. This will be both due to direct climate effects on decomposition, but also due to changes in above- and below-ground C inputs (both in quantity and quality) and possibly changes in so-called root ‘priming’ effects on the decomposition of existing organic matter. A model of soil respiration using parameters from field surveys shows that soils of the birch forest are more sensitive to increases in mean annual temperature than soils under tundra heath. The heterogeneity of soil properties, moisture and temperature regimes and vegetation cover in ecotone areas means that responses to climate change will differ across these landscapes. Any exercise in upscaling results from field surveys has to indicate the heterogeneity of vegetation and soil categories to guide soil sampling and modelling of C cycle processes in the Arctic.

No description available.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1968. / Typescript. Vita. Description based on print version record. Includes bibliographical references (leaves 127-133).

Abstract Despite the greater strategic importance and increasing activities in the Arctic as well as the increased attention paid by national governments, few attempts have been made to understand the on-going demographic changes from a pan-Arctic perspective. In particular, population aging or “silverization” is a demographic megatrend affecting regional societies and the economy which can exert profound social consequences in this most desolate and least populated region in the world. Although there are a few studies investigating aging in the Arctic countries, none have extended their research to the sub-national level. This thesis consists of an analysis of aging and possible rejuvenation trends in 23 Arctic sub-regions, and compares these trends to the national average of their eight respective countries. Two groups of indicators have been used to measure aging; these are based on “chronological” and “prospective” ages, the latter considers changes in life expectancy and improvements in population health. The study generated a large set of aging data for the period 1980/1990 to 2010 as well as the present day, utilizing the available baseline data. The discussion examined major trends in aging elucidating the interactions of conventional and prospective indicators, revealed the oldest and youngest territories, linkages between the Arctic and nationwide rates, the fastest and slowest regions that are aging (or in contrast, rejuvenating), sex and ethnic differences, and whether Northern Canada and Alaska, North Atlantic, Arctic Russia and Northern Fennoscandia are converging or diverging in terms of aging development. In addition, the interplay of causes of aging and other demographic conditions of Arctic territories was examined as well as the gaps in knowledge and prospects for future research. The international comparative evidence of the thesis can help the northern communities’ policy makers in planning changes that have to be made in order to adjust to an aging transition. It is clear that sustainable population development is the key to a viable Arctic region. / Tiivistelmä Arktisella alueella tapahtuvaa väestörakenteen muutosta ja sen syitä on tutkittu vähän, vaikka alueen merkitys ja aktiviteetit ovat korostuneet valtioiden strategioissa. Erityisesti väestön ikääntyminen tai ”harmaantuminen” on yleinen demografinen suuntaus, joka vaikuttaa pohjoisten alueiden väestöön ja talouteen ja voi johtaa syvällisiin yhteiskunnallisiin seurauksiin tällä maailman harvaan asutuimmalla alueella. Ikääntymistä on tutkittu jonkin verran yksittäisissä maissa, mutta ei näiden maiden pohjoisissa osissa. Tässä väitöskirjatyössä analysoidaan ikääntymistä ja mahdollista nuorentumista kahdeksan arktisen maan 23 pohjoisella alueella ja näitä verrataan saman maan kansalliseen keskiarvoon. Ikääntymisen mittareina on käytetty kahta mittaustapaa perustuen joko ”kronologiseen” tai ”prospektiiviseen” ikään, joista jälkimmäinen huomioi muutokset odotettavissa olevassa eliniässä sekä väestön terveydentilan kohentumissa. Tutkimuksen tuloksena syntyi laaja ikääntymistä käsittelevä tietoaineisto vuosilta 1980/1990 vuoteen 2010/nykypäivään perustuen käytettävissä oleviin lähtöaineistoihin. Tässä työssä yksilöitiin ikääntymisen pääsuuntaukset ja vertailtiin perinteisten ja uusien indikaattoreiden tuottamia tuloksia. Lisäksi selvitettiin ikääntymisen kannalta väestöltään vanhimmat ja nuorimmat alueet, verraltiin arktisen alueen ja kansallisten lukujen välisiä yhteyksiä sekä esiteltiin nopeimmin ja hitaimmin ikääntyvät (tai nuorentuvat) alueet sekä sukupuoleen ja etnisyyteen liittyviä eroja. Tutkimus luo uutta tietoa Pohjois-Kanadan ja Alaskan, Pohjois-Atlantin alueen, Venäjän arktisen alueen sekä pohjoisen Fennoskandian väestöjen ikääntymiskehityksestä. Lisäksi väitöskirjatyö analysoi ikääntymiskehityksen ja muiden väestökehitykseen liittyvien olosuhteiden syitä arktisella alueella sekä tulevaisuuden tutkimustarpeita. Kansainvälinen vertailu voi auttaa valtioiden ja alueiden päättäjiä tekemään suunnitelmat, joilla pohjoiset yhteisöt voivat sopeutua ikääntymisen tuomiin haasteisiin. Kestävä väestökehitys on avain elinvoimaiseen arktiseen alueeseen.

Arctic sea ice has undergone a dramatic transformation in recent decades, including a substantial reduction in sea ice extent in summer months. Such changes, combined with relatively recent advancements in seasonal (1-12 months) to decadal forecasting, have prompted a rapidly-growing body of research on forecasting Arctic sea ice on seasonal timescales. These forecasts are anticipated to benefit a vast array of end-users whose activities are dependent on Arctic sea ice conditions. The research goal of this thesis is to address fundamental challenges pertaining to seasonal forecasts of Arcitc sea ice, with a particular focus placed on improving operational sea ice forecasts in the Canadian Seasonal to Interannual Prediction System (CanSIPS). Seasonal forecasts are strongly dependent on the accuracy of observations used as initial condition inputs. A key challenge initializing Arctic sea ice is the sparse availability of Arctic sea ice thickness (SIT) observations. I present on the development of three statistical models that can be used for estimating Arctic SIT in real time for sea ice forecast initialization. The three statistical models are shown to vary in their ability to capture the recent thinning of sea ice, as well as their ability to capture interannual variations in SIT anomalies; however, each of the models is shown to dramatically improve the representation of SIT compared to the climatological SIT estimates used to initialize CanSIPS. I conduct a thorough assessment of sea ice hindcast skill using the Canadian Climate Model, version 3 (one of two models used in CanSIPS), in which the dependence of hindcast skill on SIT initialization is investigated. From this assessment, it can be concluded that all three statistical models are able to estimate SIT sufficiently to improve hindcast skill relative to the climatological initialization. However, the accuracy with which the initialization fields represent both the thinning of the ice pack over time and interannual variability impacts predictive skill for pan-Arctic sea ice area (SIA) and regional sea ice concentration (SIC), with the most robust improvements obtained with two statistical models that adequately represent both processes. The final goal of this thesis is to improve the quantification of uncertainty in seasonal forecasts of regional Arctic sea ice coverage. Information regarding forecast uncertainty is crucial for end-users who want to quantify the risk associated with trusting a particular forecast. I develop statistical post-processing methodology for improving probabilistic forecasts of Arctic SIC. The first of these improvements is intended to reduce sampling uncertainty by fitting ensemble SIC forecasts to a parametric probability distribution, namely the zero- and one- inflated beta (BEINF) distribution. It is shown that overall, probabilistic forecast skill is improved using the parametric distribution relative to a simpler count-based approach; however, model biases can degrade this skill improvement. The second of these improvements is the introduction of a novel calibration method, called trend-adjusted quantile mapping (TAQM), that explicitly accounts for SIC trends and is specifically designed for the BEINF distribution. It is shown that applying TAQM greatly reduces model errors, and results in probabilistic forecast skill that generally surpasses that of a climatological reference forecast, and to some degree that of a trend-adjusted climatological reference forecast, particularly at shorter lead times. / Graduate

Le réchauffement climatique dans l’Arctique canadien est deux fois plus rapide que la moyenne globale, ce qui accélère la fonte de la banquise et bouleverse radicalement la faune, la flore et les communautés de la région tout entière. Ce réchauffement est causé non seulement par la hausse des émissions de gaz à effet de serre, mais également par des agents de forçage climatique de courte durée comme les aérosols troposphériques. Toutefois, le forçage radiatif des aérosols dans la région polaire est beaucoup moins bien estimé que celui des gaz à effet de serre, notamment le CO2, et demeure toujours incertain. Cette grande incertitude résulte principalement de la grande variabilité spatiotemporelle des propriétés chimiques et physiques des aérosols, en plus de la complexité des boucles de rétroaction observées en Arctique. D’ailleurs, les données sur les caractéristiques des aérosols et de leur répartition à travers la région sont très limitées, et ce, plus particulièrement dans le Haut-Arctique canadien. Pour remédier à ce problème, une série de mesures a été effectuée sur une période de 3 ans (2016-2019) dans le laboratoire de recherche sur l’environnement atmosphérique polaire (PEARL, 80N 86O) situé près de la station météorologique d’Eureka, au Nunavut, Canada. La distribution en taille des aérosols a été mesurée en se servant de plusieurs instruments, dont un compteur optique de particules (OPC), un granulomètre de mobilité électrique à balayage (SMPS) et un granulomètre aérodynamique (APS). Les propriétés optiques des aérosols ont été déterminées avec deux extinctiomètres photoacoustiques (PAX) qui opèrent respectivement à des longueurs d’onde de 405 et 870 nm. Les observations réalisées à l’observatoire PEARL démontrent une forte variation saisonnière dans les propriétés optiques et microphysiques des aérosols polaires. Pendant l’hiver et le printemps, l’atmosphère arctique est envahie par une brume sèche d’origine anthropique qui se traduit par une forte augmentation dans la taille, la concentration en nombre et les propriétés optiques extensives des aérosols. Les épisodes de brume arctique commencent généralement en mi-décembre, où des évènements de poussières minérales ont aussi été observés, et se terminent en mai où la formation et le grossissement de nouvelles particules s’amorcent. Le début du printemps mesure les concentrations d’aérosol en mode accumulation les plus élevées durant l’année. Les aérosols les plus sombres qui composent la brume arctique ont été identifiés comme étant de la suie ou du carbone noir transporté dans l’Arctique à partir de l’Eurasie et de l’Alaska. Quelques relations systématiques entre les propriétés optiques et la distribution de taille des aérosols ont également été calculées et révèlent une différence majeure entre les aérosols interagissant avec la lumière à 405 et 870 nm. / Global warming in the Canadian Arctic is twice as fast as the global average, accelerating the melting of sea ice and radically disrupting the fauna, the flora, and the communities of the whole region. Arctic warming is caused not only by rising greenhouse gas emissions, but also by the short-lived climate forcing agents such as tropospheric aerosols. However, aerosol radiative forcing in the polar region is less precisely estimated than that of greenhouse gases, notably CO2, and remains highly uncertain. This large uncertainty arises mainly from the high spatiotemporal variability in aerosol chemical and physical properties, in addition to the complexity of the feedback loops observed in the Arctic. Furthermore, datasets on aerosol characteristics and their distribution across the region are very limited, particularly in the Canadian High Arctic. To address this issue, a series of measurements were conducted over a 3-year period (2016-2019) at the Polar Atmospheric Environment Research Laboratory (PEARL, 80N 86W) near Eureka weather station, in Nunavut, Canada. Aerosol size distribution was measured using several instruments including an Optical Particle Counter (OPC), a Scanning Mobility Particle Sizer (SMPS), an Aerodynamic Particle Sizer (APS). Aerosol optical properties were determined by two Photoacoustic Extinctiometers (PAXs) which operate at wavelengths of 405 nm and 870 nm, respectively. Observations made at the PEARL observatory show a strong seasonal variation in the optical and microphysical properties of polar aerosols. In the winter and spring, the Arctic atmosphere is impacted by an anthropogenic haze that results in a sharp increase in aerosol size, number concentration, and optical properties. Arctic haze episodes typically occur in mid-December, when mineral dust events have also been observed, and end in May when formation and growth of new particles begin. Early spring exhibits the highest accumulation-mode aerosol concentrations during the year. The darkest Arctic haze aerosols have been identified as soot or black carbon transported into the Arctic from Eurasia and Alaska. Some systematic relationships among aerosol optical properties and size distribution have also been calculated and reveal a major difference between aerosols interacting with light at 405 nm and 870 nm.

Nowadays the Arctic becomes a new arena for political and economic interrelation of different states in their will to gain future benefits, which the region can bring. The aim of the thesis is to investigate the Arctic as an area of cooperation and (or) conflict between Russia and three EU states: Denmark, Finland and Sweden as well as the EU itself. This research paper looks on the problem from the perspective of rational- choice theory of international relations, which allows comparing the Arctic strategies of observed actors and their interests in the region. Despite existence of the Arctic Council as a platform for negotiations and multilateral agreements, as well as common will to solve the disputes there is still place for uncertainties in actor' view on the development of the Arctic. For this reason the question of the Arctic region is urgent for all above mentioned countries including the EU, which seeks to take its place in the debate.

Indiana University-Purdue University Indianapolis (IUPUI) / The global climate is creating more ice-free waters in the Arctic. These new navigation possibilities around the Arctic lead to increased global trade, tourism, and oil and gas exploration. With the foreseeable increased nautical transportation through the Northwest Passage, the United States needs to revisit its security posture in and around the Bering Strait. At least five different grand strategies are potentially relevant in addressing this question. By comparing the suggestions of these leading grand strategy approaches to what has actually been implemented by the United States in the Strait of Hormuz, the Strait of Malacca, and the Panama Canal, similarities emerge that can help the United States shape their strategy for the defending of its national interests in the Bering Strait. By testing the different grand strategies against three reasonably similar cases, I find that a forward military presence and supporting a liberal institutionalist approach are the two key aspects that the United States should employ in the Bering Strait. Increasing and improving the military presence that the United States has in the region should be a top priority. In addition, supporting the Arctic Council would provide an increased level of security to the United States and other nations in the region. This strategy is not without its challenges and it will require artful statecraft in order to be successful.

No description available.

This thesis borrows the analytical framework of Qallunology to examine a nineteenth-century Arctic whaling encounter between Scottish whalers and an Inuk geographer: Inulluapik. This thesis analyzes the narrative, written by Scottish surgeon Alexander M’Donald, of Inulluapik’s transatlantic journey to Aberdeen, Scotland and Tinnujivik (Cumberland Sound) from 1839 to 1840. I show how Inulluapik’s experience in Aberdeen in 1839, as recorded by M’Donald, provides insight into early Victorian worldviews and perceptions, which I call M’Donald’s Qallunaat-dom and Qallunaat-ness. By conducting a Qallunology of M’Donald’s description of the historical episode, I examine his early Victorian Qallunaat-dom, which compared Inuit from the eastern Arctic to Scots in Aberdeen through his binary understanding of whaling, gender, and spirituality. M’Donald’s interpretation of Inulluapik’s experience demonstrated his contrasting views of Inuit and non-Inuit cultures, which intersected with early Victorian ideas of civilization, intelligence, behaviour, appearance, respectability, female domesticity and marital purity, and Indigenous authenticity. In contrast, Inulluapik demonstrated fluid resistance to M’Donald’s early Victorian binaries of subsistence versus commercial whaling, rural versus urban, primitive versus advanced, and uncivilized versus civilized, and Indigenous versus non-Indigenous. / Graduate