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1.
Geographer C. W. Thornthwaite proposed in 1948 a moisture index called Thornthwaite Moisture Index (TMI) as part of a water balance model for a new classification system for climate. The importance of TMI climatic classification has been recognised in many areas of knowledge and practice worldwide over the last 60 years. However, although past climate research was focused on developing adequate methods for climate classification, current research is more concerned with understanding the patterns of climate change. The use of TMI as an indicator for climate change is still an incipient area of research. The contributions of this paper are twofold. First, it is to fully document a methodology based on geostatistics adopted to produce a time series of TMI maps that are accurate and have high spatial resolution. The state of Victoria, in Australia, over the last century, is used as the case study. Second, by analysing these maps, the paper presents a general evaluation of the spatial patterns found in Victoria related to moisture variability across space and over time. Some potential implications of the verified moisture changes are discussed, and a number of ideas for further development are suggested.  相似文献   

2.
Nationalism, as a political discourse requiring a fundamental connection to a particular territory has constantly referred to maps as evidence of the eternal existence of the respective nation. In the case of modern Turkey, the national map has been a symptomatic signifier of a constant anxiety of territorial loss. Built around such anxiety, Turkish nationalism has been sensitive towards the borders defining national territory. This article analyzes the use of national maps as instruments for the cultural production of nationalism in Turkey throughout the last three decades. In the process, it is intended to differentiate between official maps produced under state authority and popular maps circulated in mass media.Throughout the 1980s, national maps included in school textbooks presented a country surrounded by hostile neighbors on all sides, in tune with the political climate of the Cold War. A crucial aspect of these official maps was the cartographic awareness they generated which, in the following decade, would become operational in the widespread use of the map as a nationalist sign. With the emergence of the Kurdish question in the 1990s, the national map became a key instrument in promoting nationalist sentiments with the invention of the flag-map logo as a favorite symbol. After the US-led invasion of Iraq in 2003, the Kurdish issue was projected on to Northern Iraq, and a new mode of cartographic representation was invented. “Appropriated maps” produced through the digital retouching of random maps found on the Internet visualized irredentist desires enlarging the country’s territory especially into Northern Iraq and invoking the Ottoman past. These maps, which consciously distorted geographical information, turned to historical references to sustain their cartographic validity.  相似文献   

3.
For more than a decade, climate change has been identified as an important emerging issue for protected areas. Utilising outputs from two equilibrium global vegetation models (GVMs) forced with six climate-change scenarios, this study assessed potential terrestrial biome-type change in Canada's protected area network (2,979 national parks, national wildlife areas, migratory bird sanctuaries, Ramsar sites, ecological reserves, wilderness wildlife areas and provincial parks). Vegetation-modelling results project that 37–48 percent of Canada's protected areas could experience a change in terrestrial biome type under doubled atmospheric carbon-dioxide conditions. Park and protected area planning in Canada have traditionally been founded upon enduring-feature analysis and ecoregion representation frameworks. These conservation-planning frameworks are based on climatic and biogeographic stability; assumptions that what these modelling results for Canada's protected areas and other vegetation-modelling studies indicate are untenable in an era of global climate change. Implications for protected area policy and planning in Canada are also discussed.  相似文献   

4.
The separation of geomorphology into structural and climatic disciplines is challenged. Climate, rock properties, physical processes, and geological structure are considered to be so intimately intertwined in their effect on the formation of landforms that little basis is seen for a division of the discipline into climatogenetic and structural approaches. Contrary to Lester King's view, this does not mean that climate is not a significant factor. It must unquestionably be taken into consideration and be reflected in any genetic classification of landforms. There is no doubt, for example, that pediments, though likely to occur under a variety of climatic conditions, do find their most widespread development in Africa because of a combination of favorable climatic and structural conditions (arid or semiarid climate, the compliability of rocks to weathering, and the long duration of the cycle under shield conditions undisturbed by any significant tectonic uplifting).  相似文献   

5.
The Intergovernmental Panel on Climate Change (IPCC) report, initiated in 1988, is complete, was debated at the Second World Climate Conference in November, 1990 and was subsequentty submitted to the United Nations General Assembly. IPCC: (i) asserted the reality of humanity's disturbance of the natural climate system; (ii) demanded studies to improve our knowledge of processes vulnerable to climatic changes: and (iii) called for policy responses to mitigate and adapt to these changes. Two fundamental issues are: how will global climatic change affect natural resources and human population and how will the impetus towards policy responses, particularly greenhouse gas emission reduction treaties, affect industry, the economy and trade? A necessary first step in the highly desirable and geographical aspiration of striving to link numerical climate modelling to the predictions of socioeconomic systems is increased awareness and improved understanding of current physical and social models. In this paper I review the status of numerical climatic modelling especially as it pertains to scenarios of the effects of human-enhanced greenhouse warming. These projections are of futures which are themselves the result of socio-economic predictions. Development of appropriate adaptive strategies depends crucially upon improved simulation of the continental near-surface climate and on improved spatial resolution of climate models by at least two orders of magnitude. Such increased resolution is likely to demand a thousandfold increase in computing power. The physical results of global climatic change are likely to be less significant than the social and economic effects resulting from international agreements on emission reduction Recent shifts in international research and policy responses place today's studies of global climatic change firmly at the focus of human-environment interactions and hence at the core of modern geography.  相似文献   

6.
Climatic factors have affected subsistence strategies throughout human history. In northern Europe and Russia, short-term climatic anomalies and weather extremes are commonly thought to underlie famines in the Middle Ages. However, medieval subsistence crises were not just natural disasters and medieval people were not passive victims of climatic anomalies. In addition, the capacity to cope with climatic anomalies has varied temporally and spatially throughout the Middle Ages. Yet only a few studies have explored the climatic impact on regional medieval food systems comprehensively. This article examines the significance of climate variability on subsistence crises in medieval Novgorod and Ladoga (Russia), focusing on the relationship between short-term climate anomalies and crop cultivation. In addition, this paper evaluates the impact of crop failures, frosts, and other weather phenomena on the food system. The materials are drawn from medieval sources, paleoclimatological reconstructions, and archaeological evidence. The results show that short-term climatic anomalies alone rarely lead to severe subsistence crises, and during every famine period there is evidence of other contributing factors, such as unfavourable weather phenomena, disease, or social unrest. The variety of cultivated crops and agricultural techniques is shown to increase the region’s resilience to climatic anomalies and to crop failures.  相似文献   

7.
Growing evidence of global climate change has led to global concerns over the vulnerability of agriculture to drought. Located in a semiarid environment, southern Alberta has suffered significant losses of agricultural productivity due to drought hazards in recent decades. Understanding the relationship between crop production and drought conditions is essential for coping with increasingly uncertain climate conditions. This study attempts to quantify the magnitude of crop production vulnerability to drought in southern Alberta. The standard precipitation index is used to measure drought stress in the region. The empirical results provide a detailed picture of the spatial variation in crop production vulnerability to varying drought conditions. Vulnerability maps from this study reveal that pockets in the study area may experience significant productivity loss given the existing level of adaptive capacity. While the irrigation districts have been associated with a lower level of vulnerability than dryland outside the irrigated region, uncertain water supply under varying climatic conditions coupled with increasing water allocation for non‐agricultural uses may increase the vulnerability in these districts.  相似文献   

8.
Global climate change and its consequences for humankind opens up a research field for exploring the diverse dimensions and forces of change through time. Chief among the objects of inquiry is how climatic shifts impact on ecological and social structures and developments and what human agencies are able to unfold under given conditions. Conclusions from such reciprocities can help to deliver a differentiated approach to the inroads of anthropogenic climate change. Central to this enterprise are such analytic perspectives as the discipline of anthropology can bring to researching the impact of climate change on human societies.  相似文献   

9.
本文基于黄土高原南部地区历史文献记录 ,对唐代气候冷暖波动特征进行初步研究。研究表明 ,799AD前后存在一次百年尺度的气候转寒 ,在 84 5 AD、880 AD附近还存在两次数十年尺度的气候波动。在数十年时间尺度上 ,气候寒冷与较高的气候变率相伴出现。唐代相应地区旱涝资料中没有发现冷暖变化与干湿变化在十年尺度上有显著的线性相关性。最后我们就气候波动与社会发展之间某些耦合现象作一初步的讨论。  相似文献   

10.
Tree-rings are an important tool for the investigation of paleoclimatic records for regions or periods of time with no instrumental climatic data. However, the responses of different species and sites to various climatic parameters are unusual. In the present study, we developed tree-ring-width chronologies of Cedrus deodara from three different sites of Chitral Hindukush range of Pakistan. The study was conducted to understand tree-growth climate relationship and its applicability in proxy climate investigations. The chronologies covered the past 469 to 595 years, with a mean segment length (MSL) ranging from 148 to 223 years. Climatic data obtained from the three weather stations showed strong correlation and was found useful for tree-ring climate relationships. Correlation Function (CF) and Response Function (RF) analysis showed that spring precipitation (March–May) is a critical limiting factor for tree-ring growth, and temperature prior to November may also play a major role in affecting tree ring-growth. The results exposed that the three sites have continuous relationship indicated that only single species from different locations are affected by the same environmental variables and hence can be used in climate reconstruction in combination. The Cedrus deodara chronologies developed at different locations had several corresponding narrow and wide marker rings indicating a large macroclimatic response to regional climatic conditions. The current study suggests that the tree-rings of Cedrus deodara from the Chitral Hindukush range could be used to develop chronologies for the reconstruction of seasonal climatic variables.  相似文献   

11.
In this essay a method of computing tourism climatic indices (TCIS) is described. These indices represent a quantitative evaluation of world climate for the purposes of international tourism. A series of rating systems is developed to provide a systematic basis for assessing the climatic elements that most affect the quality of the tour- ism experience. The problem of weighting climatic variables in the TCI formula is also discussed. Monthly TCIS have been computed for 453 meteorological stations throughout the world, and the results have been generalized in 12 monthly world maps.
L' article offre une méthode pour calculer des indices climatoogiques touristiques (ICT), qui représentent une évaluation quantitative des climats mondiaux, destinée aux besoins du tourisme international. On développe une série de systèmes d' évaluation d' éléments climatologiques, fournissant ainsi une base systématique pour évaluer lesquels de ces derniers influencent le plus la qualityé de l' expérience touristique vécu. L'article souléve aussi les problhes réliés aux valeurs relatives, soient les poids, des variables qui entrent dans la formule de l' ICT. Des valeurs mensuelles ont été compilées pour 453 stations météorologiques à travers le monde, et les résultats sont présentés, en forme généralisée sur une base mensuelle, dans douze cartes mondiales.  相似文献   

12.
Temperate rainforest is restricted to a globally rare set of climatic conditions. Scotland has among the best remaining examples of intact temperate rainforest in Europe, characterised ecologically by a unique assemblage of epiphytic bryophytes and lichens. Given climatic control on rainforest distribution and ecology, climate change is a probable risk to Scotland’s rainforest. This study investigated climate change impacts for 20 target sites, classified based on (i) bioclimatic conditions, and (ii) epiphytic diversity, into contrasting rainforest and more continental (non-rainforest) examples. Space-for-time matching identified climate analogues within the European conservation forest network, which at present have a climate similar to that expected of the target sites during the 2080s (WorldClim datasets). The results show that 2080s analogues for sites in more continental north-eastern Scotland occur in Wales and southern England. However, Scottish rainforest sites were their own ‘best analogues’ through to the 2080s, despite the fact that their climate is projected to change significantly; they had no suitable future analogue within Europe’s conservation forest network. These contrasting regional patterns highlight the need for a flexible approach to species conservation during climate change, including a strategy to cope with ecological uncertainty in Scotland’s zone of oceanic rainforest.  相似文献   

13.
Recent developments in the Soviet Union's program of national thematic mapping and regional complex mapping are reviewed. A comprehensive mapping program along these lines, formulated in 1969 by GUGK, the government planning agency, has not been implemented. National thematic maps in the Soviet Union continue to be compiled by individual government agencies without coordination and without uniformity in legend and design, so that comparability is made difficult. The only thematic GUGK maps now being prepared are concerned with two long-term regional development programs in the Soviet Union–the rural development plan for the Nonchernozem zone of the European RSFSR and the construction of the Baykal-Amur Mainline (BAM) railroad in the Soviet Far East. The need for a comprehensive and coordinated program of national thematic maps and regional atlases or map series is once again stressed in connection with economic planning and environmental problems, and a program of continuously updated regional atlases, based on digital data banks, is proposed. Suggestions are also made for the coordination of thematic maps at the international level.  相似文献   

14.
This study examines the climate‐related methods of adaptation on which the traditional Arab house in the Eastern Mediterranean was based. We analysed nine old houses (from the 18th century to the early 20th century), built in the Arab vernacular tradition style, in three areas of Israel with different climatic conditions. Three houses in each area were chosen at random. Only nine were chosen because of the difficulty in finding houses whose state of preservation was in keeping with the aims of the research. For each house, climate‐related elements of the construction were documented. We found elements included at the design stage indicating climate consciousness, climate‐related elements due to building constraints, and building constraints in a cultural context with implications for the balance of climatic efficiency. The findings showed that climatic considerations were an integral part of the design while the principles crossed the boundaries of the three areas. Temperature, relative humidity, and heat intensity were measured, both inside and outside the house on selected days in each season. The research showed that the house moderates the impact of the outside temperature, inside the house in winter and mainly during the hot hours of the day in summer. Most of the climate‐related elements are still relevant. They can be used in regions with Mediterranean‐type climates (in the Mediterranean Basin, South Africa, central Chile, and southwestern Australia), especially when global warming and air pollution demand a substantial revolution of building design philosophies, strategies, technologies, and management methods.  相似文献   

15.
ABSTRACT

Sustainable flood risk management in Scotland is underpinned by the Flood Risk Management (Scotland) Act 2009. Effective delivery of actions to reduce the adverse impact of flooding are dependent on a collaborative approach by Responsible Authorities and a common understanding of flood hazard and risk. Over the last few decades, flood hazard maps have established a prominent role as essential tools in supporting effective flood risk management. They have developed as a result of improved national datasets and advances in computer processing. Improvements in modelling confidence and in the spatial representation of hazard and risk-inform confident actions set out in Flood Risk Management Strategies that coordinate actions supporting adaptation to future hazard conditions. The continued development of the accurate spatial representation of flood hazard and risk is an essential component of enhancing resilience in the face of future climate change.  相似文献   

16.
In this article, which is part of a series on national atlases, the author makes recommendations for the selection of maps and map content to be incorporated into the atlas section devoted to the water resources of the land. She divides the maps into two major classes: maps of drainage patterns, and maps of the characteristics of stream regime.  相似文献   

17.
With considerable evidence demonstrating the intrinsic importance of weather and climate for tourist decision-making, the projected redistribution of climatic resources as a result of climate change is anticipated to have important consequences for temporal and spatial patterns of tourism demand. Some of the world's leading coastal tourism destinations (Mediterranean and Caribbean) have been identified as becoming ‘too hot’ for tourism. However, the microclimates of coastal tourism areas have not been considered by such assessments. With a focus on thermo-physiologically relevant climatic parameters, this paper examines the adaptive range of microclimatic conditions available in two coastal resort settings in the Caribbean islands of Barbados and Tobago. Recorded weather parameters include air temperature, black globe temperature, relative humidity, and wind speed. The microclimatic results, which are presented using the Universal Thermal Climate Index (UTCI), show that hourly thermal conditions can range up to 4 °C in different outdoor areas of the resort property (beach, garden, pool, cabana). This is salient in terms of characterizing tourism destinations for climate change assessments, as the results reveal that thermal conditions can vary at the micro-scale of a coastal resort, with the ability for tourists to attain thermally comfortable conditions within a single resort property. When a location becomes thermally uncomfortable (i.e. too hot), tourists can change their location (e.g. move from the pool to the beach), providing an onsite adaptive range between 1 °C and 4 °C. The results also demonstrate that thermo-physiologically relevant climatic parameters provide a more precise estimate of the available range of thermal comfort than is inferred from ambient temperature alone. The findings are discussed in the context of tourists’ climatic preferences and reveal that the microclimatic conditions recorded in this study (UTCI 29–36 °C) are well within tourists’ preferred thermal conditions and do not exceed tourists’ thermal thresholds for coastal tourism.  相似文献   

18.
Palaeoanthropologists and archaeologists have long invoked climate change to explain aspects of human evolution. Collection of new climatic and environmental data combined with new fossil discoveries and methodological improvements continue to make exploration of this link a vital endeavour in studying human evolution. The current study employs a global climatic dataset and a rigorously compiled catalogue of hominin first and last appearance dates to test the effects of changes in temperature on hominin speciation and extinction. Through the use of wavelet analysis and bandpass filters the eccentricity, obliquity, and precession components of the studied climatic record are extracted and tested independently for associations with patterns of speciation and extinction. Results suggest that all three components may play a role in speciation events, but that only the obliquity cycle shows a statistically significant relationship with extinction events. It is suggested that, whilst climatic factors could contribute to the appearance of new hominin species, subsequent competition between these species may lead to their extinction.  相似文献   

19.
中国南方十一座旅游名城避寒疗养气候旅游资源评估   总被引:6,自引:0,他引:6  
文章对人体健康与气候环境作了分析,阐明寒冷气候与呼吸道系统、心血管系统、消化道系统疾病发病率、死亡率的对应关系。运用生理气候舒适度指数,对中国南方11座旅游名城的避寒气候作了横向分析比较,得出中国最佳避寒疗养地的区域格局,为开展中国冬季避寒疗养旅游提供了发展基础。  相似文献   

20.
X-ray powder diffraction (XRD) analysis of clays from anthropogenic Late Holocene reservoir sediments can provide a paleoclimatic proxy. Illite and smectite are climate sensitive clay minerals and their relative amounts correlate with climatic episodes. Relative percent composition of clays in Late Holocene reservoir sediment is diagnostic of different mineral source areas and their hydraulic transport processes, which are climate controlled. Climosequences of clay minerals from Late Holocene reservoir sediments are correlative with magnetic susceptibility records and provide a relatively simple and cost-effective tool for gaining insight into paleoclimate.  相似文献   

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