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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
261

An investigation of the pattern scaling technique for describing future climates

Mitchell, Timothy D. January 2001 (has links)
No description available.
262

Elevated carbon dioxide and gas exchange in groundnut and sorghum

Singleton-Jones, Paul January 1998 (has links)
No description available.
263

Satellite measurements of surface temperatures

Jung, Fan January 1992 (has links)
No description available.
264

An investigation into the impact of environmental change upon the vegetation of Widdybank Fell, Upper Teesdale

Lewthwaite, Katherine Jane January 1999 (has links)
Widdybank Fell is located in the Upper Teesdale National Nature Reserve in the Northern Pennines. It is internationally renowned for its unique late-glacial relict assemblage of plant species, particularly those on the "sugar limestone” outcrops. Cow Green Reservoir was constructed in the early 1970s and flooded the lower western slopes of Widdybank Fell. At the time there was concern amongst ecologists that the reservoir might alter the local climate and have adverse effects on the remaining vegetation. A comprehensive vegetation survey of Widdybank Fell was carried out by Jones (1973). Aspects of this survey were repeated as part of the present study. There have been significant changes in the composition of some of the plant communities since the 1970s. These changes include a considerable loss of bryophyte diversity and lichen abundance. Overall there has been a decline in "stress tolerant" species, and a loss of calcicole species on the calcareous grasslands. Few of the nationally rare plant species have changed in abundance. Using data from the meteorological stations at Widdybank Fell and from nearby Moor House, it has been demonstrated that the presence of Cow Green Reservoir has resulted in significant changes in the local climate. These changes are consistent with those expected by a classic "lake effect" and include the all year round moderation of minima (e.g. resulting in a reduction in the number of ground frosts). The reservoir has also produced cooler mean air temperatures in spring and warmer mean temperatures in autumn. Despite the observed local climate impact of Cow Green Reservoir it seems most likely that other factors have been responsible for the observed vegetation changes. Acid deposition has probably caused the loss of calcicoles on the calcareous grasslands, and atmospheric nitrogen deposition could explain the loss of bryophyte diversity and lichen abundance.
265

Development of My Footprint Calculator

Mummidisetti, Karthik 01 January 2017 (has links)
The Environmental footprint is a very powerful tool that helps an individual to understand how their everyday activities are impacting environmental surroundings. Data shows that global climate change, which is a growing concern for nations all over the world, is already affecting humankind, plants and animals through raising ocean levels, droughts & desertification and changing weather patterns. In addition to a wide range of policy measures implemented by national and state governments, it is necessary for individuals to understand the impact that their lifestyle may have on their personal environmental footprint, and thus over the global climate change. “My Footprint Calculator” (myfootprintcalculator.com) has been designed to be one the simplest, yet comprehensive, web tools to help individuals calculate and understand their personal environmental impact. “My Footprint Calculator” is a website that queries users about their everyday habits and activities and calculates their personal impact on the environment. This website was re-designed to help users determine their environmental impact in various aspects of their lives ranging from transportation and recycling habits to water and energy usage with the addition of new features that will allow users to share their experiences and their best practices with other users interested in reducing their personal Environmental footprint. The collected data is stored in the database and a future goal of this work plans to analyze the collected data from all users (anonymously) for developing relevant trends and statistics.
266

Process and Emergence| A Topographic Ethnography of the Embodiment of Place and Adventure Tourism in Khumbu, Nepal

Jackson, Mary A. 07 June 2017 (has links)
<p> Adventure is a relic of imperialism and the European romanticization of place. It has evolved from quests for domination of place and people (colonialism), to spiritual or consumeristic escape from the modern world, to an attempt to return or reconnect to nature. This paradigm implies that if humans must reconnect to nature, there is an inherent disconnect or a separation. This reconnection is rooted in romantic notions and Cartesian duality of man and nature. However, approaches towards adventure and tourism apart from such dominant Western mountain traditions focus on the critical and contextually based aspects of adventure experiences. These approaches, informed by indigenous meanings of place, traditional ecological knowledge, and ecofeminism, decenter human experience. Likewise, a feminist new materialist approach towards understanding place and materiality also allows for an awareness of entanglements and intra-active relationships of human and more-than-human to emerge, as did this research. </p><p> This dissertation examined place in the context of adventure trekking tourism in the upper Solukhumbu District, Nepal through a walking ethnography of the trails in and around Mount Everest base camp. This research was based on the following questions: 1. How can the future of development of Nepali Himalayan adventure tourism industry move forward ethically and with reciprocity towards the interconnectivity of mountains and people; 2. How can the adventure tourism industry consider the complexities of influence on a place&mdash;from both a direct impact and that of greater anthropogenic impacts? This research was grounded in the background and orientations of Everest tourism, which developed within discourse and materiality of Khumbu, shifting with local identities and meanings of place. Tourism in this context mangles in the edges of local and global cultures looming within immanent threats of the Anthropocene. Discourse composed and idealized from outside the mountain boundaries contributes to motivations for traveling to the Khumbu and perceptions of this place, in turn shaping the expectations of the tourist. In these contact zones mountains are sacred, a business venture, a personal challenge, place of revelation and spirituality, imperial conquest, neocolonial stomping ground, to scientific object of study. Within these complexities, this dissertation examined the concept of place and how meaning and agency develop in relation to adventure tourism experiences in Khumbu and the Anthropocene. A reciprocity develops in which human amongst more-than-human becomes embedded and inseparable. Shifting an anthropocentric gaze that privileges and sets matter apart as isolated and constrained by boundaries determined by humans, demonstrated the vibrant agential reality of more-than-human intimacies such as forgotten landscapes, rocks, dirt, glaciers, and altitude. Nature is not a passive object upon which humans descend, but rather an entangled subjectivity. This awareness allows for a rethinking of human enactments of Anthropocene and complicit behaviors of this epoch, reframing approaches to adventure. The conclusions of this research found that mountains&mdash;more-than-human&mdash;have agency and meaning and are not passive or in the background of human experience. This applies to a practical application of the research through a praxis tool for new materialist research and the adventure industry, in turn decentering the human/anthropocentrism and identified practices of tourism that are both sustainable and more inclusive of the entanglements of people and place.</p>
267

Adaptation to climate change at ports, regions and supply chains

Zhang, Huiying 07 September 2016 (has links)
With increasing awareness of the potential impacts posed by climate change, many ports and their surrounding regions have undertaken adaptation planning and proactive actions so as to build a resilient and sustained business. However, most of them are still at the embryonic stage in understanding the problem and find it very challenging regarding adaptation planning and implementation. This thesis addresses the current issue in adaptation to climate change impacts at ports, regions and supply chains through quantitative and qualitative analyses. A global survey is designed to investigate port decision-makers’ perceptions and knowledge about climate change adaption. It explores the existing impacts posed by sea level rise (SLR), and high winds and storms, and demonstrates the potential impacts of adaptation measures. Analytical results suggest that, despite the forecast of more serious impacts posed by these climate change risks in the near future, port decision-makers still have strong doubts about the effectiveness of adaptation measures and planning. In-depth interviews in a case study on Port Metro Vancouver (Canada) are conducted to further investigate the barriers (especially institutional ones) that hinder the process of climate change adaptation, and thus calls attention for its regional efforts. Based on the literature review and analysis, this study argues that a paradigm shift in adaptation planning, notably from ‘go it alone’ to ‘collaborative’ approach involving all major port stakeholders, is urgently needed. The thesis also highlights the pivotal role of tailor-made adaptation methods in accordance with a specific climate change risk in the adaptation planning. Besides, two innovative, ‘paradigm shift’ recommendations are proposed to climate adaptation planning: (1) a method based on usage unit to allocate investment responsibility; and (2) the establishment of a neutral agency (e.g., a collaborative network) with the power to promote the adaptation process. In addition, a flexible combination of engagement in collaborative projects and individual efforts for ports is suggested so as to implement adaptation works. / October 2016
268

Effects of climate change on freezing damage in three subarctic bryophyte species

Kassel, Marlene January 2017 (has links)
Climate change is expected to have a strong impact on subarctic ecosystems. Increased temperatures as well as altered precipitation and snow cover patterns are predicted to change species distribution and affect biogeochemical processes in the subarctic tundra. Bryophytes are an essential vegetational component in northern ecosystems, due to their high abundance and importance in many ecological processes. In this study the effects of elevation and altered snow cover on the temporal dynamics of freezing damage in three subarctic bryophyte species (Hylocomium splendens, Ptilidium ciliare, and Sphagnum fuscum) were studied in a snow manipulation field experiment in Abisko, during early spring. Soil temperature and field moisture of moss shoots were collected. A freeze-thaw incubation experiment was conducted to investigate the freeze-thaw cycle resistance of H. splendens and P. ciliare originating from habitats with two differing snow-cover thicknesses. Freezing damage differed significantly between the bryophytes species with P. ciliare experiencing the least and S. fuscum the highest damage. Damage was higher at the low elevation, possibly attributable to acclimation effects. Snow removal led to higher damage in moss shoots, but no interactions of the different snow cover treatments with elevation, species or time were found. Freezing damage increased over time and no recovery occurred, likely due to temporal patterns in soil freeze-thaw cycles during early spring. Soil freeze-thaw cycles were the main factor influencing damage in bryophytes after snow melt. Measured environmental parameters could not explain the entire variation in damage. Damage might additionally be attributable to increased UV radiation or disturbances by herbivores.
269

Klimatanpassning av dagvattenhantering : Hur arbetar kommuner i Västra Götalands län med klimatanpassning av sin dagvattenhantering?

Glennvall, Julia January 2016 (has links)
The purpose of this report was to investigate how municipals in the county of Västra Götaland work with climate adaptation of storm water management and to identify problems that occur in the work. As with the rest of the world, Sweden will be affected by expected climate changes and it is therefore important that Swedish municipalities work with climate adaptation and to help them make the work manageable. The method used was semi-structural qualitative interviews where 13 municipalities were interviewed in April 2016. The result of the interviews shows that there is an ambition to work with climate adaptation of storm water management but that there are different problems associated with the work that have made it difficult to start. 69% of the municipalities include climate adaptation to some extent when they work with master plans and 5 out of 8 municipalities are or will be including climate adaptation strategies in their storm water management document. A majority of the municipalities don’t prioritize climate adaptation and could be doing more to include climate adaptation in their work. The most common problems reported by the municipalities were too little resources/lack of finance, undecided responsibility and not clear enough laws regarding the subject.
270

Ranking of tree-ring based temperature reconstructions of the past millennium

Trouet, Valerie, Esper, Jan, Krusic, Paul J., Ljungqvist, Fredrik C., Luterbacher, Juerg, Carrer, Marco, Cook, Ed, Davi, Nicole K., Hartl-Meier, Claudia, Kirdyanov, Alexander, Konter, Oliver, Myglan, Vladimir, Timonen, Mauri, Treydte, Kerstin, Villalba, Ricardo, Yang, Bao, Buntgen, Ulf 01 August 2016 (has links)
Tree-ring chronologies are widely used to reconstruct high-to low-frequency variations in growing season temperatures over centuries to millennia. The relevance of these timeseries in large-scale climate reconstructions is often determined by the strength of their correlation against instrumental temperature data. However, this single criterion ignores several important quantitative and qualitative characteristics of tree-ring chronologies. Those characteristics are (i) data homogeneity, (ii) sample replication, (iii) growth coherence, (iv) chronology development, and (v) climate signal including the correlation with instrumental data. Based on these 5 characteristics, a reconstruction-scoring scheme is proposed and applied to 39 published, millennial-length temperature reconstructions from Asia, Europe, North America, and the Southern Hemisphere. Results reveal no reconstruction scores highest in every category and each has their own strengths and weaknesses. Reconstructions that perform better overall include N-Scan and Finland from Europe, E-Canada from North America, Yamal and Dzhelo from Asia. Reconstructions performing less well include W-Himalaya and Karakorum from Asia, Tatra and S-Finland from Europe, and Great Basin from North America. By providing a comprehensive set of criteria to evaluate tree-ring chronologies we hope to improve the development of large-scale temperature reconstructions spanning the past millennium. All reconstructions and their corresponding scores are provided at www.blogs.uni-mainz.de/fb09climatology. (C) 2016 Elsevier Ltd. All rights reserved.

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