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161.
We examine environmental aspects of the conflict between the Turkish state and the insurgent Kurdistan Workers Party (Partiya Karkerên Kurdistan or PKK). Since the early 1990s, several civil society groups have claimed that the Turkish army burned forests and destroyed other livelihood resources in the Kurdistan region of Turkey as it evacuated settlements. We report the results of a case study of destruction in Tunceli, eastern Turkey, undertaken in order to evaluate support for such claims. We demonstrate the use of geospatial techniques in case-specific approaches to the study of armed conflict. Through the analysis of satellite images, we verified eyewitness reports and confirmed that substantial burnings did indeed take place in the study area between 1991 and 1994. We argue that this destruction was not irrational or wanton, but that it was part of a strategy used by the Turkish army in the early 1990s that aimed at actively transforming the war environment.  相似文献   
162.
Liu  Syalie  Altay  Sacha  Mercier  Hugo 《Climatic change》2022,170(1-2):1-21

As the world’s largest fossil fuels exporter, Russia is one of the key countries for addressing global climate change. However, it has never demonstrated any significant ambitions to reduce greenhouse gas (GHG) emissions. This paper applies ideational research methodology to identify the structural differences in economic, political, and social normative contexts between industrialized fossil fuel importing economies and Russia that lead to the fundamental gap in motivations driving decarbonization efforts. Russia is unlikely to replicate the approach to the green transition and climate policy instruments of energy-importing countries. In order to launch decarbonization in Russia, interested stakeholders need to frame climate policies in Russia differently. Specifically, the framing must address the priority of diversification as a means to adapting the national economy to a new green landscape, the combination of diverse channels for decarbonization, the promotion of energy-efficiency, closer attention to climate-related forest projects, and linkage of climate change with other environmental problems. Moreover, considering Russia’s emissions as a part of the global economic system and shifting from a simplistic national focus on GHG emissions reduction would help coordinate policies through dialogue between exporters and importers of fossil fuel energy-intensive goods, which is essential for the global movement towards a net-zero future.

  相似文献   
163.
Climate change will have serious repercussions for agriculture, ecosystems, and farmer livelihoods in Central America. Smallholder farmers are particularly vulnerable due to their reliance on agriculture and ecosystem services for their livelihoods. There is an urgent need to develop national and local adaptation responses to reduce these impacts, yet evidence from historical climate change is fragmentary. Modeling efforts help bridge this gap. Here, we review the past decade of research on agricultural and ecological climate change impact models for Central America. The results of this review provide insights into the expected impacts of climate change and suggest policy actions that can help minimize these impacts. Modeling indicates future climate-driven changes, often declines, in suitability for Central American crops. Declines in suitability for coffee, a central crop in the regional economy, are noteworthy. Ecosystem models suggest that climate-driven changes are likely at low- and high-elevation montane forest transitions. Modeling of vulnerability suggests that smallholders in many parts of the region have one or more vulnerability factors that put them at risk. Initial adaptation policies can be guided by these existing modeling results. At the same time, improved modeling is being developed that will allow policy action specifically targeted to vulnerable groups, crops, and locations. We suggest that more robust modeling of ecological responses to climate change, improved representation of the region in climate models, and simulation of climate influences on crop yields and diseases (especially coffee leaf rust) are key priorities for future research.  相似文献   
164.
165.
Solar global radiation, air temperature, relative humidity, and wind speed were measured in Coronel Oviedo, Paraguay, within the path of totality of the eclipse of 3 November 1994. Global radiation decreased gradually as the sun was being eclipsed and became negligible during the totality, then increased to their normal values. Surface air temperature decreased significantly, about 3 C, with the lowest value occurring about 7 minutes after totality. Relative humidity, because of its dependence on temperature, increased as a consequence of the temperature decrease. Surface wind speed decreased gradually during the eclipse, as a result of the cooling and stabilization of the atmosphere. Although atmospheric pressure was also measured, it was not possible to record pressure changes clearly associated to the eclipse, since the pressure sensor was only able to detect pressure variations of at least 1 hPa.  相似文献   
166.
"The separation of environmental and population issues globally is reflected in the fact that the setting of international agendas to tackle them was for all intents and purposes undertaken at separate international meetings--the Earth Summit in Rio de Janeiro in 1992 and the International Population Conference in Cairo in 1994. This paper presents an overview of Australia's international involvement in population issues and suggests that until recently Australia had played a minor political role in international population initiatives primarily, and perhaps ironically, because it has been a world leader in demographic research and teaching for several decades."  相似文献   
167.
The 28 March 1996 earthquake (Mw=5.7) produced extensive damage in Pujili, a small town located in the central part of the Inter-Andean valley of Ecuador. Variations in the damage rate of adobe constructions throughout the city let us suppose a ground motion amplification related to site effects. A site effect study using the H/V spectral ratio confirmed the good agreement with geological formations and showed that a second peak in some soil response appears at sites that are located over a zone of alluvial deposits, in the most damaged area of the city. This second peak is in the frequency range 5–7 Hz, close to the natural response of adobe building frequency. Thus, the second peak seems to increase the damage rate of adobe buildings and may be related to superficial alluvial deposits of a river, acting independently of the rest of the soil column.  相似文献   
168.
169.
Datasets produced by different countries or organisations are seldom properly aligned and contain several discrepancies (e.g., gaps and overlaps). This problem has been so far almost exclusively tackled by snapping vertices based on a user-defined threshold. However, as we argue in this paper, this leads to invalid geometries, is error-prone, and leaves several discrepancies along the boundaries. We propose a novel algorithm to align the boundaries of adjacent datasets. It is based on a constrained Delaunay triangulation to identify and eliminate the discrepancies, and the alignment is performed without moving vertices with a snapping operator. This allows us to guarantee that the datasets have been properly conflated and that the polygons are geometrically valid. We present our algorithm, our implementation (based on the stable and fast triangulator in CGAL), and we show how it can be used it practice with different experiments with real-world datasets. Our experiments demonstrate that our approach is highly efficient and that it yields better results than snapping-based methods.  相似文献   
170.
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