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1.
The author, another opponent of large reservoirs in Western Siberia, analyzes the effect of such large inland water areas on the moisture and heat supply of the region. He predicts that the construction of a reservoir would result in a southward shift of the optimal moisture and heat conditions for agriculture and would have an adverse cooling effect on climate, especially In summer.  相似文献   

2.
The use of fire is essential for the preparation of hafting adhesives; both are suggested to be a proxy for distinguishing the technological expertise and complex cognition among Palaeolithic populations. While use of fire has been argued to exist from about 1.0 Ma onwards, evidence for adhesives in the Palaeolithic record is rare and fragmented. In spite of the close link between fire places and adhesives, no study has ever focussed on examining the impact of heat on adhesive deposition and preservation. This paper discusses the results of a combustion experiment that was undertaken to understand the impact of heat exposure on hafting adhesives. The results have significant implications for archaeological interpretations. Deposition in or near a fire proves to severely impact the types of residues that preserve on a stone tool. The vertically transferred heat is responsible for the loss of adhesives but also for the incidental production of adhesives and their deposition on stone tools. It can be hypothesised that the rare survival of adhesives on archaeological stone tools might not only be the result of direct contact with the fire but also the result of degradation due to heat from overlying fireplaces. If we are to improve our understanding of the preservation of adhesives, it is important to unstand the taphonomic processes that affect these adhesives, in particular heat alteration.  相似文献   

3.
全球气候变化是人类历史上对文明生存的最大挑战。近年来,世界各国出现了几百年来历史上最极端的天气,它的出现与人类活动密不可分。为此,世界各国展开了包括行政手段和技术手段等在内的应对气候变化的方法,城市规划也是一个关注和讨论的重点领域。但是,目前这些方法仍旧延续了原有城市规划的原则和方法,现实指导作用较为有限。特别是对于快速城市化地区,如何通过调整规划原则和方法,编制能应对气候变化的城市或区域规划,仍是亟待探索和实践的问题。因此,本文就快速城市化地区如何应对气候变化提出了一系列的城市规划原则与方法,并将其深入落实在南京新一轮城市规划中。  相似文献   

4.
ABSTRACT. Oosterhaven (1988) labels the supply-driven input-output model “theoretically implausible” and criticizes the straightforward use of the model for impact studies. This comment extends and corrects some of the issues addressed by Oosterhaven. We derive the characteristics which industry production relations must possess to be consistent with the implied changes in industry inputs and outputs when supply-side input-output models are employed for impact analysis. First, it is shown that an implicit assumption is the characteristic of perfect substitutability among all inputs in each industry production function. This is the polar opposite of the Leontief assumption of zero elasticity of factor substitution among all inputs, and is very unrealistic for large changes from the initially observed solution since it implies that all inputs are non-essential in the production process and that any input can be substituted for all others simultaneously. Second, it is shown that the model may still be reasonable for approximating the effect of small changes since the implied production relation may be interpreted as a cost minimizing choice for a standard constant-returns-to-scale production function linearized around the initial solution under the assumption that relative prices are unchanged. Under this alternative interpretation, the supply-side model may be expected to provide a reasonable approximation, useful for analyzing changes in the neighborhood of the initial solution, but would appear to be inappropriate for analyzing large changes.  相似文献   

5.
《Political Geography》2007,26(6):695-715
The conventional discourse relating climate change to conflict focuses on long term trends in temperature and precipitation that define ecosystems and their subsequent impact on access to renewable resources. Because these changes occur over long time periods they may not capture the proximate factors that trigger conflict. We estimate the impact of both long term trends in climate and short term climatic triggers on civil conflict onset in Sub-Saharan Africa. We find that both operationalizations have a significant impact. Climates more suitable for Eurasian agriculture are associated with a decreased likelihood of conflict, while freshwater resources per capita are positively associated with the likelihood of conflict. Moreover, positive changes in rainfall are associated with a decreased likelihood of conflict in the following year. We also assess the outlook for the future by analyzing simulated changes in precipitation means and variability over the period 2000–2099. We find few statistically significant, positive trends in our measure of interannual variability, suggesting that it is unlikely to be affected dramatically by expected changes in climate.  相似文献   

6.
The mounting evidence for climate change has put the security implications of increased climate variability high on the agenda of policymakers. However, several years of research have produced no consensus regarding whether climate variability increases the risk of armed conflict. Many have suggested that instead of outright civil war, climate variability is likely to heighten the risk of communal conflict. In particular, erratic rainfall, which reduces the availability of water and arable land, could create incentives for violent attacks against other communities to secure access to scarce resources. Yet, whether groups resort to violence in the face of environmentally induced hardship is likely to depend on the availability of alternative coping mechanisms, for example through market transfers or state accommodation. This suggests that the effect of rainfall anomalies on communal conflict will be stronger in the presence of economic and political marginalization. We evaluate these arguments statistically, utilizing a disaggregated dataset combining rainfall data with geo-referenced events data on the occurrence of communal conflict in Sub-Saharan Africa between 1990 and 2008. Our results suggest that large negative deviations in rainfall from the historical norm are associated with a higher risk of communal conflict. There is some evidence that the effect of rainfall shortages on the risk of communal conflict is amplified in regions inhabited by politically excluded ethno-political groups.  相似文献   

7.
A sudden decline of solar activity around 850 calendar years BC caused a shift to a cool and wet climate in northwest Europe. Food production suddenly became problematic because of shorter, wetter growing seasons and increased night frost. This climate change triggered innovation and the development of a new agricultural system in continental northwestern Europe: arable farming on raised beds (Celtic field banks) laid out in a more or less checked pattern. This kind of agriculture mitigated the effects of the climate shift by providing better drainage and lessening damage by night frost and thus lengthening the growing season. Once the advantages of this kind of cultivation, soil enrichment and optimum root growth besides the hydrological effects, became obvious it will have been practised on a large scale and introduced when people thought it useful, independent of the local hydrological situation.  相似文献   

8.
Climate change is expected to have a severe impact on cultural heritage in the future. This study presents the methodology developed during the FP7 project Climate for Culture, of assessing the climate change impact on collection objects in cultural heritage buildings. The main innovation lies in coupling new high resolution future climate projections with building simulation tools in order to predict future indoor climate and identify future risks in historic buildings. The case study is an intermittently heated wooden chapel in Croatia. The whole building simulation model of the chapel was validated using a newly developed method of accuracy assessment in the context of preventive conservation. Even though modeling intermittent heating induces limitations in the model, it can be used for computing of future indoor data. Future indoor climate data was assessed for possible risks of biological, mechanical, and chemical damage to painted wooden panels using the newly developed specific climate risk assessment. When using this method of damage assessment on buildings with active climate control, especially with intermittent heating, it is recommended to determine the relevant season for the damage process in order to objectively analyze results.  相似文献   

9.
Remains from Paleo-Eskimo cultures are well-documented, but complete preservation is rare. Two kitchen middens in Greenland are known to hold extremely well-preserved organic artefacts. Here, we assess the fate of the Qajaa site in Western Greenland under future climate conditions based on site characteristics measured in situ and from permafrost cores. Measurements of thermal properties, heat generation, oxygen consumption and CO2 production show that the kitchen midden can be characterized as peat but produces 4–7 times more heat than natural sediment. An analytical model from permafrost research has been applied to assess future thawing of the midden. Results show that the preservation conditions are controlled by freezing temperatures and a high water/ice content limiting the subsurface oxygen availability. Threats to the future preservation are related to thawing followed by drainage and increasing subsurface oxygen availability and heat generation. The model predicts that the unique 4000-year-old Saqqaq layer below more than 1 m of peat is adequately protected against thawing for the next 70 years.  相似文献   

10.
This paper argues that the net economic impact of new firm locations or expansions is determined by a multitude of opposing forces. Using a unique database, I set out to evaluate the net effects of these opposing forces by looking at the net change in local employment and population arising from large (greater than 300 new jobs) firm locations or expansions in the State of Georgia. The analysis suggests that the employment multipliers associated with new firm locations are much less than one; that is, the net employment effect of a large firm opening is smaller than the gross employment impact. This result is consistent with other empirical economic impact studies, which find multipliers much smaller than those of typical input–output models, often less than unity, and a previous study showing little net effect of large plant openings. Expansions of existing establishments are shown to have substantial multiplicative effects, however, with an average employment multiplier of 2.0. I discuss possible reasons for differential impacts across new and expanding firms, focusing on the nature of the firms. Differences in net impact across industries and high‐tech versus low‐tech firms also is evaluated. I find that the impact of large firm locations or expansions on population in the resident county generally is negative, but positive for the broader region encompassing the county of location and its contiguous neighbors.  相似文献   

11.
The Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) raised public awareness of the need to consider climate change in coastal management and gained international recognition when it received a joint award of a Nobel Peace Prize in 2007. The raised awareness of climate change surrounding the work of the IPCC was in large part responsible for the focus of the recent Australian national inquiry into coastal management in the context of potential climate change impacts on the coast, conducted by the House of Representatives Standing Committee on Climate Change, Water, Environment and the Arts. In the same year the then Minister of Climate Change, Senator Penny Wong, and the Department of Climate Change released a major government report Climate Change Risks to Australia's Coast and set up a national Coasts and Climate Change Council to provide advice to the government. This paper provides a review and analysis of the extent to which climate change issues, within the context of the broader global change debate, have influenced Australian coastal management through its legislation, policies and practice. In particular, the paper focuses on the impact of recent national reports and state government legislative and policy changes and draws conclusions on future directions for Australian coastal management.  相似文献   

12.
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   

13.
吴普  周志斌  慕建利 《人文地理》2014,29(3):128-134
气候变暖背景下避暑旅游成为夏季旅游市场的主旋律。地方政府及旅游主管部门在培育避暑旅游目的地时应从何入,手旅游者如何能够准确地做出避暑旅游决策等是一个现实问题。本文在综述国内外相关研究与实践的基础上,认为舒适凉爽的夏季气候条件只是避暑旅游的最基本条件,创新性地提出应侧重从产业发展的角度,引入旅游休闲度、游客满意度和综合风险度等指标。避暑旅游评价指标体系的构建为目的地避暑旅游条件评估提供了理论框架,有助于游客准确地做出避暑旅游决策,同时也为目的地避暑旅游发展与提升提供一个具操作性的管理工具。  相似文献   

14.
Urban heat island (UHI) effect is an important impact factor of the regional climate and ecological environment. How to observe and analyse the spatial distribution of UHI has become an important issue of urban environmental research. In this paper, the near‐surface air temperature of Beijing was derived based on the Landsat/TM satellite imagery on 26 July 2011 to study the near‐surface UHI. A statistical model at 195‐m window size was established to estimate the air temperature, using land surface temperature, normalized difference vegetation index, altitude, and surface albedo as independent variables. The mean absolute error (MAE) of the model was 0.87°C, and the R2 was 0.66, indicating that the method can be used to effectively estimate the air temperature. The air temperature distribution obtained from remote sensing revealed that the UHI effect in Beijing was very significant and showed a concentrated pattern. The heat island intensity was stronger in the southern part than in the northern part of the city. In addition, the relationship between the air temperature and impervious surfaces was analysed. The air temperature increased with increasing impervious surface coverage, and the rate of change depended on the impervious surface coverage. When the impervious surface coverage was below 40 per cent, the temperature increased rapidly with increasing impervious surface coverage, and when the impervious surface coverage was above 40 per cent, the temperature increased slowly. This study provides a new approach to monitor near‐surface UHI and reveals its relationship with impervious surface, providing a scientific reference for urban planning and environmental assessment.  相似文献   

15.
Focussing on the cotton improvement projects in Dharwar, western India, that exemplified the modernising aims of colonial agriculture in nineteenth-century India, this article interrogates the architecture of cotton imperialism in the colonised world through the conceptual lens of political ecology. In particular, it brings to the fore the crucial dimension of climate both as an element in colonial thinking and planning, and as a dynamic force impacting on the cultivation of transplanted American cotton. The climate of Dharwar was not quite what the cotton authorities had constructed it to be, and it was, moreover, undergoing change due to the impact of regional deforestation. Furthermore, the article shows how this failure to come to terms with local climate conditions and changes was symptomatic of a broader failure to consider the overall agricultural livelihoods of peasant cultivators. Apart from a brief period when prices were artificially high, peasants much preferred growing the accustomed indigenous cotton rather than the new exotic variety. In turn, cotton was less of a priority than the production of millet food crops. By exploring the ways in which climatic conditions interacted with the economic, social and technological processes of cotton production in Dharwar, this article highlights why American cotton cultivation failed to meet colonial expectations during this period while also revealing the fragile architectural edifice of colonial power.  相似文献   

16.
This paper offers a historical micro-level analysis of the impact of climate shocks on the incidence of civil conflict in colonial Nigeria (1912–1945). Primary historical sources on court cases, prisoners and homicides are used to capture conflict. To measure climate shocks we use the deviation from long-term rainfall patterns, capturing both drought and excessive rainfall. We find a robust and significant curvilinear (U-shaped) relationship between rainfall deviations and conflict intensity, which tends to be stronger in agro-ecological zones that are least resilient to climatic variability (such as Guinean Savannah) and where (pre-) colonial political structures were less centralized. We find evidence that the relationship is weaker in areas that specialize in the production of export crops (such as cocoa and palm oil) compared to subsistence farming areas, suggesting that agricultural diversification acts as an insurance mechanism against the whims of nature. Additional historical information on food shortages, crop-price spikes and outbreaks of violence is used to explore the climate–conflict connection in greater detail.  相似文献   

17.
Rapid urbanisation and industrialisation have resulted in sharp land cover changes. Urban change not only impacts on land cover but also on urban climate. Land surface and atmospheric modifications due to urbanisation generally lead to a modified thermal climate that is warmer than the surrounding, non-urbanised areas. In this research remote sensing technology was used to evaluate urban growth patterns and its thermal characteristics through mapping impervious surfaces and evaluating thermal infrared images. The case study was carried out in the northern part of Ho Chi Minh City, which has experienced accelerated urban development since the late 1980s. Landsat and Aster images were used to calculate variations in urban impervious surfaces from 1989 to 2006. Thermal bands were processed to obtain radiant surface temperatures for investigating the urban heat island effect associated with increasing impervious surfaces, both spatially and temporally. Impacts of urban development on surface temperature were shown by investigating the surface urban heat island effect intensity. The results show that the built-up area in the northern part of Ho Chi Minh City expanded by 6.5 times between 1989 and 2006. Urban development has altered the magnitude and pattern of the surface urban heat island, with the highest land surface temperature cores found in the industrial (greater than 45oC) and urban areas (within 36oC and 40oC). In suburban and rural areas, where agricultural land still remains with full vegetation cover, the land surface temperature is usually lower. Using remote sensing, the impervious surface was extracted with overall accuracy and a Kappa coefficient for all three years greater than 96%, and the retrieved land surface temperatures with variations from in-situ measurements of less than 2oC. The results presented here indicate that remote sensing can help to spatially monitor urban development and land surface temperature changes over the whole area and over a long period of time.  相似文献   

18.
Historical park visitation and weather data, taken at the daily time scale from 2000 to 2009 for Pinery Provincial Park in southern Ontario (Canada), were analysed as an objective measure of the weather sensitivity, temperature thresholds, and potential impacts of projected climate change for park visitation. Three seasonal weather-visitation models were constructed using multivariable linear regression (peak, shoulder, off-season). To account for both natural and institutional seasonality, the weather-visitation models included both climatic (temperature, precipitation) and social (weekends, holidays) variables, which demonstrated equably comparable effects on visitation across the three models. Critical temperature thresholds were identified for each season using one-way analysis of variance to determine the range of temperatures within which the threshold was evident; the specific degree of temperature associated with the threshold was identified within the seasonal regression models. Temperatures over 33 °C during the peak season and over 29 °C during the shoulder season indicated critical thresholds at which point conditions that were ‘too hot’ for some caused a decline in visitation. Furthermore, temperatures below 11 °C indicated another critical threshold, where conditions were ‘too cold’ for most and therefore park visitation was less sensitive to temperature variability below this threshold. A partial sensitivity analysis for the impact of a warmer, wetter climate on park visitation was conducted, illustrating the effect of a 1 °C to 5 °C warming in maximum temperatures, coupled with a 5% to 15% increase in total precipitation. In response to projected climate change, the weather-visitation models suggested that for each additional degree of warming experienced, despite the negative effects of increasing precipitation and more frequent heat extremes, annual park visitation could increase by 3.1%, annually. The projected increase in park visitation as a result of rising temperatures was mainly associated with shoulder season visitation, with only minor increases in peak season visitation.  相似文献   

19.
This article presents the local gender contract of a smallholder irrigation farming community in Sibou, Kenya. Women's role in subsistence farming in Africa has mostly been analyzed through the lens of gender division of labor. In addition to this, we used the concept of ‘local gender contract’ to analyze cultural and material preconditions shaping gender-specific tasks in agricultural production, and consequently, men's and women's different strategies for adapting to climate variability. We show that the introduction of cash crops, as a trigger for negotiating women's and men's roles in the agricultural production, results in a process of gender contract renegotiation, and that families engaged in cash cropping are in the process of shifting from a ‘local resource contract’ to a ‘household income contract.’ Based on our analysis, we argue that a transformation of the local gender contract will have a direct impact on the community's adaptive capacity climate variability. It is, therefore, important to take the negotiation of local gender contracts into account in assessments of farming communities' adaptive capacity.  相似文献   

20.
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   

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