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[en] Improved knowledge of the contributing sources of uncertainty in projections of Arctic sea ice over the 21st century is essential for evaluating impacts of a changing Arctic environment. Here, we consider the role of internal variability, model structure and emissions scenario in projections of Arctic sea-ice area (SIA) by using six single model initial-condition large ensembles and a suite of models participating in Phase 5 of the Coupled Model Intercomparison Project. For projections of September Arctic SIA change, internal variability accounts for as much as 40%–60% of the total uncertainty in the next decade, while emissions scenario dominates uncertainty toward the end of the century. Model structure accounts for 60%–70% of the total uncertainty by mid-century and declines to 30% at the end of the 21st century in the summer months. For projections of wintertime Arctic SIA change, internal variability contributes as much as 50%–60% of the total uncertainty in the next decade and impacts total uncertainty at longer lead times when compared to the summertime. In winter, there exists a considerable scenario dependence of model uncertainty with relatively larger model uncertainty under strong forcing compared to weak forcing. At regional scales, the contribution of internal variability can vary widely and strongly depends on the calendar month and region. For wintertime SIA change in the Greenland-Iceland-Norwegian and Barents Seas, internal variability contributes 60%–70% to the total uncertainty over the coming decades and remains important much longer than in other regions. We further find that the relative contribution of internal variability to total uncertainty is state-dependent and increases as sea ice volume declines. These results demonstrate that internal variability is a significant source of uncertainty in projections of Arctic sea ice. (letter)
[en] The Agency has received a communication dated 30 March 2009 from the Permanent Mission of Iceland to the Agency regarding Iceland's nuclear policies and practices. As requested therein, the communication is attached herewith for the information of Member States
[en] The extensive lava piles of Iceland contain a unique record of geomagnetic field variations spanning the past ~ 16 Ma. Since the 1950s, palaeomagnetic data have been obtained from over 9400 Icelandic lavas. We have compiled all palaeomagnetic data currently available and developed a publicly accessible database ( http://www.icepmag.org ). The data within the database are primarily palaeodirections, with a relatively smaller number of palaeointensity data (8936 entries contain direction only, 218 intensity only, and 337 both direction and intensity). In addition, the database contains a wide range of metadata, including geochronological information, site details, and laboratory methods. The search interface of the database allows users to search for data using a range of customisable filters (e.g. by publication, geological age, location, laboratory method, palaeomagnetic statistics) and to quickly visualise and download the matching search results. The data within the database have significant potential for understanding long-term palaeomagnetic field variations at high latitude, the behaviour of excursions and reversals, and geological mapping on Iceland. .
[en] In the autumn of 2000 the Icelandic Radiation Protection Institute began systematic analysis of radiocaesium in Icelandic soils. The main objectives of the study are to investigate the spatial variation of radiocaesium concentration in Iceland and make estimates of the retention of Cs-137 in major soil types. Soil samples from 17 sampling sites were collected. Soils were sampled with a 17 mm sampling probe. Twenty cores were collected at each site at even intervals along a 20 m on line. The concentration of Cs-137 was measured using HPGe spectrometry. The main results gained so far are the following: a) Total activity per unit area of Cs-137 was found to be 900-4700 Bglm2. b) In all cases > 85 % of Cs-137 in soils is fixed in the uppermost 15 cm of the soil cover. c) In loam and sandy loam 60-95 % of Cs-137 is fixed in the top layer of the soil (i.e. 0-5 cm interval). In sandy loam and loamy sand (Vitric Andosols) considerable amount of Cs is fixed in deeper layers, i.e. below 5 cm depth, indicating that mobility of Cs-137 is dependent on grain size distribution and clay content of the soil. Former studies indicate that Cs is rather mobile in Icelandic soils. d) In pieat (Histosols) 80-85% of Cs-137 is bound in the top layer of the soil (0-5 cm) and 10-15% within the 5-10 cm depth range. e) Comparison of samples obtained form undisturbed hayfield and uncultivated land at the same site (i.e. MYR) showed lower concentration of Cs-137 in the top layer of the hayfield but on the other hand higher total activity per unit area. Sample from GRI, collected in a hayfield, shows similar behaviour of Cs-137 as in MYRa. f) Good correlation was obtained between precipitation and total activity of radiocaesium in soils. In the autumn of 2000 the Icelandic Radiation Protection Institute began systematic analysis of radiocaesium in Icelandic Soils. The main objectives of the study are to investigate the spatial variation of radiocaesium concentration in Iceland and make estimates of the retention of Cs-137 in major soil types. Soil samples from 17 sampling sites were collected. Soils were sampled with a 17 mm sampling probe. Twenty cores were collected at each site at even intervals along a 20 m long line. The concentration of CS-137 was measured using HPGe spectrometry. (LN)
[en] From 1965 to 1990, 46 cases of malignant nasopharyngeal tumours were diagnosed in Iceland. The incidence rate is as low as in other Western countries, 0.6/100 000 per year. Histo-pathological diagnosis were as follows: Undifferentiated carcinoma 45%; squamous cell carcinoma 30%; non-keratinizing carcinoma 7%; and plasmacytoma 9%; lymphoma 7%; rhabdomyosarcoma 2%. Four per cent were diagnosed at stage I, 13% at stage II, 29% at stage III and 54% at stage IV. The overall crude survival at 10 years from diagnosis was 28.3%. The following factors were found to have a prognostic value: Stage of disease, size of tumour (T-classification) and age at diagnosis. Nodal stage (N-classification) alone and sex were not found to be prognostic factors. There was no difference in survival among the different WHO types of cancer. Patients with carcinoma were all treated with radiotherapy. The survival of those who received more than 60 Gy was better than of those who received 60 Gy or less (p=0.04). (orig.)
[en] For over a thousand years seaweeds have been sundered in Iceland for various uses, but geothermal heat was utilized for the first time for drying of seaweed in Hveragerdi 1939. During the sixties various experiments were carried on the drying of several types of seaweeds, grass, capeline and mussell in various sizes and types of experimental through-circulation dryers. On the bases of these experiments, a 5-belt through-circulation dryer was selected for the drying of seaweeds and possibly the mentioned marine and agricultural products in the commercial drying station built at Teykholar, W-Iceland, where seaweed meal has been produced since 1975. Results of drying experiments are compared with drying parameters in the commercial drying station at Teykholar, and the available data on drying of seaweeds using geothermal energy is summarized and compared with data from Scotland and Canada. The author looks to the future for the drying and possibly cultivation and extraction of chemicals by geothermal heat from seaweeds and various other heat sensitive products available in Iceland. Without geothermal energy seaweed industry would not exist in Iceland nor would this paper
[en] Present research programme (long-term) - Analysis of the background activity in commercially important fish species in Icelandic waters: To gain information on the background activity (whole beta and different gammas) in commercially important fish species around Iceland before experimental work with radionuclides begins. Also important in case of incidental contamination of the surrounding waters
[en] A Surtseyan volcanic eruption involves a bulk interaction between water and hot magma, mediated by the return of ejected ash. Surtsey Island, off the coast of Iceland, was born during such an eruption process in the 1940s. Mount Ruapehu in New Zealand also undergoes Surtseyan eruptions, due to its crater lake. One feature of such eruptions is ejected lava bombs, trailing steam, with evidence that watery slurry was trapped inside them during the ejection process. Simple calculations indicate that the pressures developed due to boiling inside such a bomb should shatter it. Yet intact bombs are routinely discovered in debris piles. In an attempt to crack this problem, and provide a criterion for fragmentation of Surtseyan bombs, a transient mathematical model of the flashing of water to steam inside one of these hot erupted lava balls is developed, with a particular focus on the maximum pressure attained, and how it depends on magma and fluid properties. Numerical and asymptotic solutions provide some answers for volcanologists.
[en] The paper presents some new concepts of hydrogen production in Iceland for domestic use and export. A brief overview of the Icelandic energy consumption and available resources is given. The cost of producing hydrogen by electrolysis is calculated for various alternatives such as plant size, load factors and electricity cost. Comparison is made between the total cost of liquid hydrogen delivered to Europe from Iceland and from Northern America, showing that liquid hydrogen delivered to Europe from Iceland would be 9% less expensive. This assumes conventional technology. New technologies are suggested in the paper and different scenarios for geothermally assisted hydrogen production and liquefaction are discussed. It is estimated that the use of geothermal steam would lead to 19% lower hydrogen gas production costs. By analysing the Icelandic fishing fleet, a very large consumer of imported fuel, it is argued that a transition of fuel technology from oil to hydrogen may be a feasible future option for Iceland and a testing ground for changing fuel technology. (Author)