Heat,smoke and fuel consumption in a high mountain stállo-hut,northern Sweden – Experimental burning of fresh birch wood during winter

The overall aim of this study was to investigate in situ, the use of an open fire for heating a traditional mountain Sami stállo-hut during winter using fresh mountain birch as fuel. The study took the form of repeated actualistic experimentation and the following parameters were recorded: fuel consumption and logistics, indoor temperature, CO-levels inside the hut and temperature in both the hut and the traditional Sami stone-lined hearth with a stone filling of flat stones. Our results show that fresh birch is an effective fuel and that about 3.6 kg (dry weight) of wood was used per hour; it took a few hours of work per day to obtain the firewood required. The highest temperature recorded beneath the stone filling in the hearth was 437.7 °C. The hearth stored a lot of heat but this did not affect the indoor temperature during the night. The highest indoor temperature indoor was +26.9 °C, but it was generally much lower and varied considerably during the day and in relation to the outdoor temperature. The CO-levels reached 112 ppm at floor level and co-varied with the smokiness experienced inside the hut.     

Impacts of urban living labs on sustainability transitions: mechanisms and strategies for systemic change through experimentation

ABSTRACT

Urban Living Labs (ULL) are considered spaces to facilitate experimentation about sustainability solutions. ULL represent sites that allow different urban actors to design, test and learn from socio-technical innovations. However, despite their recent proliferation in the European policy sphere, the underlying processes through which ULL might be able to generate and diffuse new socio-technical configurations beyond their immediate boundaries have been largely disregarded and it remains to be examined how they contribute to urban sustainability transitions. With this study, we contribute to a better understanding of the diffusion mechanisms and strategies through which ULL (seek to) create a wider impact using the conceptual lens of transition studies. The mechanisms of diffusion are investigated in four distinct ULL in Rotterdam, the Netherlands and Malmö, Sweden. The empirical results indicate six specific strategies that aim to support the diffusion of innovations and know-how developed within ULL to a broader context: transformative place-making, activating network partners, replication of lab structure, education and training, stimulating entrepreneurial growth and narratives of impact.     

Job polarization in the new economy in Danish cities: location,size, and the role of the public sector

ABSTRACT

In this paper we examine the geographic patterns of employment growth and employment polarization in small and medium-sized cities (SMCs) in Denmark during the rise of the new economy. The geography of employment polarization in Danish cities is examined using register-based employment data on occupations and wages divided into the public and private sectors in the period 1993–2006; it therefore covers a long period of transformation and growth in the Danish economy. We conclude that employment growth is characterized by employment polarization combined with growth in low- and high-wage employment and a decline in medium-wage employment. However, these patterns of polarization differ across the public and private sectors, as well as by geography. While local labour market (LLM) size, city position and city specialization influence the geography of private-sector employment growth and polarization, municipal population and composition influence the geography of public-sector growth patterns across wage levels. Finally, public and private employment are positively associated within SMCs, predominantly driven by the positive association between public employment and private-sector low-wage employment. However, public employment is not associated with an increase in private low-wage employment in more remote areas.     

Urban experimentation & sustainability transitions

ABSTRACT

This special issue deals with various research questions regarding the impact of urban experimentation on transitions towards sustainability in different industries and sectors. Cities have been identified to play a vital role for sustainability transitions. Not only are they places with an increased urgency for change, but they also bring about many current sustainability initiatives and interventions. This special issue focuses on investigating the relationship between urban experimentation and institutional change. The articles shed light on various characteristics of urban environments that influence experimentation and potentially lead to institutional change and thus elaborate on some of the distinct mechanisms through which urban experimentation can lead to broader systemic changes.     

Testing for the presence of thermal pretreatment of flint in the mesolithic and neolithic of Sweden

Through ethnographic accounts, the method of heat treatment of silica materials to improve the flaking qualities is shown to have been known almost worldwide. Some mesolithic and neolithic flint artifacts from southern Sweden were examined in order to determine if they too were heat treated. From several methods proving or indicating thermal alteration of flint, analysis using scanning electron microscopy was chosen. Two samples were taken from each artifact, one being examined unaltered, the other being heat treated. No two samples from the same artifact had the same kind of surface appearance. Thus these analyses prove that the artifacts examined had not been heat treated.     

Distal cryptotephra found in a Viking boathouse: the potential for tephrochronology in reconstructing the Iron Age in Norway

Distal tephra deposits from Icelandic volcanic eruptions have been found in Norway and can be used to precisely date a variety of sedimentary environments. Tephrochronology has not yet been applied to archaeological investigations in Norway because tephra are generally not found as visible layers, but are present as very low concentrations of glass shards (i.e. cryptotephra). In this study, we present results from the analysis of cryptotephras found in an Iron Age boathouse in northern Norway. The boathouse was associated with the chieftain center at Borg on Vestvågøy in the Lofoten Islands. In 2003, a trench was excavated and the stratigraphy of the boathouse was described. Radiocarbon ages from cultural deposits show that it was constructed in the Early Iron Age c. AD 540–660 and the main period of use was at the end of the Iron Age between c. AD 1030 and AD 1270. Volcanic glass shards were isolated from sediment samples collected above and below the cultural deposit representing the main period of use. Electron microprobe analysis of the glass shards showed that the lower sample resembles the AD 860 Layer B tephra and the upper sample resembles tephra erupted from the Hekla volcanic system between AD 1104 and AD 1300. These tephrochronologic dates agree with the radiocarbon-derived dates and possibly further constrain the boathouse’s main period of use to c. AD 1030–1104. Our results demonstrate the value of using tephrochronology for archaeological studies in Norway and the potential for finding cryptotephra from other large explosive volcanic eruptions during the Iron Age.