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51.
A baseline climatology is required in evaluating climate variability and changes on regional and local scales. Gridded climate normals, i.e. averages over a 30‐year period, are of special interest since they can be readily used for validation of climate models. This study is aimed at creating an updated gridded dataset for Swedish monthly temperature normals over the period 1971–2000, based on standard 2‐m air temperature records at 510 stations in mainland Sweden. Spatial trends of the normal temperatures were modelled as functions of latitude, longitude and elevation by multiple linear regression. The study shows that the temperature normals are strongly correlated with latitude throughout the year and especially in cold months, while elevation was a more important factor in June and July. Longitude played a minor role and was only significant in April and May. Regression equations linking temperature to latitude, longitude and elevation were set up for each month. Monthly temperature normals were detrended by subtracting spatial trends given by the regressions. Ordinary kriging was then applied to both original data (simple method) and de‐trended data (composite method) to model the spatial variability and to perform spatial gridding. The multiple regressions showed that between 82% (summer) and 96% (winter) of the variance in monthly temperature normals could be explained by latitude and elevation. Unexplained variances, i.e. the residuals, were modelled with ordinary kriging with exponential semivariograms. The composite grid estimates were calculated by adding the multiple linear trends back to the interpolated residuals at each grid point. Kriged original temperature normals provided a performance benchmark. The cross–validation shows that the interpolation errors of the normals are significantly reduced if the composite method rather than the simple one was used. A gridded monthly dataset with 30‐arcsecond spacing was created using the established trends, the kriging model and a digital topographic dataset.  相似文献   
52.
Anisotropy of magnetic susceptibility and structural geology of the ca. 1.45 Ga Karlshamn pluton (southern Sweden) are used to study its emplacement and structural evolution. The Karlshamn pluton is one of the largest metaluminous A-type granitoid intrusions in southern Sweden. It is a multiphase body made up of two suites that differ in composition but which have similar crystallization ages. The magmatic foliation, ductile shear zones and granite–pegmatite filled fractures were mapped as well as the metamorphic foliation and extension lineation in the metamorphic host rocks. The anisotropy of magnetic susceptibility was used to map the magnetite petrofabric of the pluton, providing a larger data set for both the magmatic foliations and lineations, which could not be mapped in the field. The fabrics within the pluton are continuous with the metamorphic fabrics in the country rocks. Both the pluton and the country rock fabrics were folded during ENE–WSW compression, while the pluton was still a magma mush. The stress field orientation during cooling of the pluton is determined on the basis of magmatic, ductile and brittle structures in the Karlshamn pluton that formed successively as the pluton cooled. The compressional event is referred to as the Danopolonian orogeny and therefore the Karlshamn granitoids, and other plutons of similar composition and age in central and southern Sweden, on the Danish Island of Bornholm, and in Lithuania, may be considered as syntectonic intrusions and not as anorogenic, as was previously thought.  相似文献   
53.
54.
Glacifluvial deposits along an ice-marginal zone in Småland, southern Sweden, have been dated using post-IR blue OSL. To test for incomplete bleaching, we adopted two strategies: analysis of modern analogues and small-aliquot dose distributions. Samples of modern fluvial sediments show no significant incomplete bleaching; they yield equivalent doses of only 0.5–2 Gy (0.25–4% of our glacifluvial sediment doses). Small-aliquot dose distributions do not provide any evidence for incomplete bleaching.

The sediments are believed to have been deposited during deglaciation and appear to fall into two age groups: 19–25 ka (mainly sandur sediments) and 33–73 ka (mainly deltaic sediments). Compared to the expected ages (13–15 ka), even the younger glacifluvial OSL ages appear up to 10 000 years (25 Gy) too old. The ages are nevertheless stratigraphically consistent and correspond between sites; we deduce that the 19–25 ka ages are true deposition ages. For glacifluvial sedimentation to take place on the South Swedish Upland at this time either a very early deglaciation is required, or alternatively ice-free conditions just prior to the LGM. The deltaic sediments (33–73 ka) were most likely not significantly bleached during deposition and thus they date events prior to the latest ice advance.  相似文献   

55.
A conventional amino acid analyzer was modified to allow detection of dissolved free amino acids in a direct injection of 0.5 to 2.0 ml of seawater. The amino acids were monitored fluorimetrically by reaction with o-phthaldialdehyde after column chromatography. The accuracies of two commonly employed desalting methods, cation exchange resin and copper Chelex, were determined by comparison with the direct injection method. After correcting the results of the desalting methods for the procedural blank and recovery rate for each individual amino acid, the amino acid compositions on a mole percent basis as determined by these methods resembled approximately the true composition determined by direct injection. However, on an absolute basis the cation resin method overestimates and the copper Chelex method underestimates the total amount of dissolved free amino acids. The reasons for these discrepancies are discussed. Using the direct injection method, the spectra of dissolved free amino acids in surface seawater samples from different locations were determined. As opposed to the relatively uniform patterns reported in most past investigations, the amino acid spectra found were highly variable. In a number of samples, the acidic amino acids dominated the spectra. Valine was also high in many samples. In a depth profile the deep samples were dominated by arginine. Application of the method to real-time shipboard analyses of dissolved free amino acids is discussed.  相似文献   
56.
Two fast‐growing stalagmites from a cellar vault in Uppsala, southeast Sweden, are analysed for their luminescent properties. The results indicate that variations in luminescence intensity in the stalagmites are annual. Due to problems in finding a suitable absolute dating method this assumption cannot yet be firmly tested; however, results from radiocarbon dating of one of the stalagmites do not contradict the proposal that the laminae are annual. If so, the speleothems have been growing for 10–15 years with a growth rate of 3–8 mm per year, which is a similar rate to other fast‐growing speleothems in Great Britain that have formed from the reaction of lime mortar and carbon dioxide. It is likely that the assumed annual laminae of the luminescence record represent a flush of organic material.  相似文献   
57.
Geological structures suggest that the Fennoscandian Shield was subjected to a higher seismicity at the end of the last glaciation than today. This article demonstrates the use of varved clay chronology for dating paleoseismic events. It is argued that the deposited annually layered glacial varves were sensitive to past ground movements. In the Stockholm area, the Erstavik varved clay chronology suggests four paleoseismic events: a first (I) dating from varve year 10,473 to 10,468 BP; a second (II) 10,451 to 10,445 BP; a third (III) 10,429 to 10,425 BP; and a fourth (IV) 10,409 to 10,404 BP. In De Geer's ‘old' (1940) chronology the first (I) dating corresponds with −1117 to −1112, the second (II) with −1095 to −1089, the third (III) with −1073 to −1069, and the fourth (IV) with −1053 to −1048. The most pronounced event was the one at around varve year 10,429 BP (varve −1073 in De Geer's ‘old' chronology). The recurrence time of about 20 years suggests a totally different seismic regime at the time of deglaciation than what exists today. It coincided with the period of maximum isostatic uplift. The complexity of the varved clay response to seismic events is also discussed.  相似文献   
58.
The development and deployment of carbon capture and storage (CCS) are sensitive to public debates that socially frame the technology. This study examines the evolving CCS debates, focusing on the media's framing of firms. Corporations are central CCS actors, and we analyze them in light of the nation-state, which has been emphasized in previous research as the primary context of CCS politics. Empirically, we compare framings of Statoil and Vattenfall in the Norwegian and Swedish media, drawing on a qualitative dataset of news media articles published between 2005 and 2009. We conclude that firms make regular media statements either to foster legitimacy or to respond to criticism of CCS. We also conclude that framing is not necessarily linked to technological success or failure and that interpretations of the technology have different forms depending on whether the related activity occurs in domestic or foreign markets. Finally, we explain the media framings based on the domestic energy situation and politics.  相似文献   
59.
Reindeer husbandry's strong connection to the land, together with the ongoing climate-change debate, has generated growing interest in its socio-ecological resilience and vulnerability. The ability of indigenous societies and their activities to respond to change is widely recognized to be dependent on several factors, such as socioeconomic forces and aspects of governance, all of which have long historical backgrounds. However, although historians constantly address questions about human societies, there have been very few historical studies on their resilience, vulnerability and adaptation strategies. Here, using historical sources, we analyze the vulnerability of reindeer husbandry (and the Sami societies that depended on it) in Sweden during the 19th century. We demonstrate that although reindeer management was a much more diverse enterprise at that time than it is now, the major adaptation strategy and constraining forces were similar to those of today. The foremost adaptation strategy was, and still is, the flexible use of pasture area, and the clearest constraints during the 19th century were the loss of authority over the land and the imposed regulation of reindeer management-both of which were strongly connected to the process of colonization.

Terminology

Throughout this paper we use the terms reindeer management and reindeer pastoralism interchangeably. Sami reindeer pastoralism has been described as a complex system with two different aspects of management: herding and husbandry. Husbandry has been defined as the accumulations of profit whereas herding has been defined as the control of the animals in the terrain (Paine, 1970, p. 53). In a Swedish context husbandry questions concerning slaughter and castration of reindeer were discussed within the household and herding matters were resolved jointly within the traditional working community Siida. The Siida consisted of households working together on traditional pasturelands and these constellations were grouped together into administrative reindeer pasture districts (Sami villages) ( [Ingold, 1978], [Fellman, 1910] and [Beach, 1981]).  相似文献   
60.
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