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1.
利用NCL滤波方法将NCEP提供的FNL风场资料分离出天气尺度,准双周振荡(QBWO,Quasi-Biweekly Oscillation)和热带季节内振荡(MJO,Madden-Julian Oscillation)环流场,研究不同时间尺度环流对台风"天鹅"(1515)突变路径的影响。台风路径的特征能够分3个阶段,其中第二阶段台风发生突然转折。第一阶段,天气尺度上台风东侧的反气旋和QBWO环流场中的波列共同引导台风向西偏北方向运动,而MJO环流场中的引导气流作用较小;第二阶段,天气尺度上台风东侧的反气旋和低频环流场中台风附近的气旋共同促进了"天鹅"近90°的突然转向,其中,高、低频分量分别促使台风突然向北、向东转向;第三阶段,天气尺度上的气旋与反气旋、QBWO环流场中的反气旋以及MJO环流场中的脊共同引导"天鹅"向东北方向运动,其中MJO环流场中气旋附近的偏东风促使"天鹅"向西运动,但由于它被天气尺度上强烈的偏西风所抵消,故"天鹅"仍向东运动。 相似文献
2.
The consequences of wildfires are felt in susceptible communities around the globe on an annual basis. Climate change predictions in places like the south-east of Australia and western United States suggest that wildfires may become more frequent and more intense with global climate change. Compounding this issue is progressive urban development at the peri-urban fringe (wildland–urban interface), where continued infrastructure development and demographic changes are likely to expose more people and property to this potentially disastrous natural hazard. Preparing well in advance of the wildfire season is seen as a fundamental behaviour that can both reduce community wildfire vulnerability and increase hazard resilience – it is an important element of adaptive capacity that allows people to coexist with the hazardous environment in which they live. We use household interviews and surveys to build and test a substantive model that illustrates how social cohesion influences the decision to prepare for wildfire. We demonstrate that social cohesion, particularly community characteristics like ‘sense of community’ and ‘collective problem solving’, are community-based resources that support both the adoption of mechanical preparations, and the development of cognitive abilities and capacities that reduce vulnerability and enhance resilience to wildfire. We use the results of this work to highlight opportunities to transfer techniques and approaches from natural hazards research to climate change adaptation research to explore how the impacts attributed to the social components of social–ecological systems can be mitigated more effectively. 相似文献
3.
J. Anthony Stallins 《Climatic change》2004,66(1-2):137-150
Weather-related hazards are the result of interactions between the physicalenvironment and the demographics of the community that experience them.Numerous studies have documented urban heat island (UHI) modification ofcloud-to-ground lightning flash densities, but none have linked flashes to theunderlying demographics. In this study, I compared flash and housing densitiesfor 25 counties encompassing Atlanta, Georgia, using ordination andcartographic visualization. Over the interval 1992-2000, two denselypopulated suburban counties downwind from Atlanta (Gwinnett and Dekalb)exhibited the highest cloud-to-ground flash densities. By contrast, highpopulation density counties located upwind (Cobb) and encircling the centralcity (Fulton) had relatively lower flash densities. Based on the interactionsamong demographics, flash density, and geographic position for a subset ofcounties, I outline four types of urban lightning hazards: emergent,UHI-augmented, UHI-suppressed, and non-interactive. For urban lightninghazards, the often invoked idea of `more people equals more hazards' is to anextent simplistic. Urban areas have a large range of lightning hazards asheating nodes emerge, intensify, and shift in response to historicallycontingent patterns of growth. 相似文献
4.
Scientific evidence for global environmental change in Africa presents a prima facia case for increased human migration and displacement. Closer scrutiny of the evidence on demographic change, however, suggests that migration and displacement are less important variables in explaining the human dimensions of global environmental change on the continent than is commonly projected. Natural population growth in cities is a more important dynamic in the evolving system of human settlement in Africa and this significant shift in where people live, both now and in the future is overlooked by the emphasis on the potential impact of environmentally induced migration. Even without any movement from the countryside, cities represent the fastest growing sector of the sub-Saharan African population. The existing vulnerability of African cities, with their fast growing populations and weak management means any environmental change is likely to have significant consequences for cities. Taking the sub-Saharan African demographic evidence seriously means that the scholarly and policy emphasis currently directed to GEC migration and displacement might be more effectively redirected to questions of the interface between global environmental change and urban areas. 相似文献
5.
社会经济发展道路的选择影响城乡发展模式,带来城市和农村人口新的分布格局.本文基于IPCC共享社会经济路径（SSPs）框架,采用第六次中国人口普查数据,综合考虑中国人口政策和迁移规律,对人口-发展-环境分析模型（PDE）中的生育率、死亡率和迁移率参数进行本地化处理,开展5种SSPs路径下的中国及分省（区、市）城乡人口预估研究,并分析其变化的主要影响因素.结果表明：1）5种SSPs路径下中国城市人口均有所增加,2015-2050年增长3.4（2.2~3.7）亿人;农村人口持续降低,减少约3.0（1.1~4.0）亿人;到2050年中国城市化率将达到79%（67%~86%）.2）未来中国大部分省份城市人口都将较2015年有所增加,西部省份的增长速度高于东部省份;所有省份农村人口都将明显减少,东部地区农村人口减少幅度高于西部地区.相比2015年,2050年西藏、新疆等地城市人口最多可增加两倍以上;大部分省（区、市）农村人口可减少60%以上.3）未来大部分路径下自然变动对城市和农村人口均由正的影响逐渐变为负影响;机械变动对城市人口影响为正,对农村人口影响为负,影响程度逐渐减小.人口自然变动在东西部省份的差异是导致东西部城乡人口不同变化的主要因素. 相似文献
6.
在全球气候变化和城市化进程加快的背景下,城市气象灾害及其影响越来越突出,呈现和传统气象灾害不一样的特征和演变规律。国内外都非常重视城市气象灾害的研究,强调气候变化的驱动和多学科综合研究是一种趋势。中国城市气象灾害有暴雨、低温冰冻、高温热浪等多种类型,对城市的社会、经济等方面产生了重要影响,因此很多学者十分关注城市气象灾害及其城市经济和社会影响研究。随着新型城市气象灾害潜在风险增加,城市气象灾害引致城市环境的脆弱性和人文社会学科引入城市气象灾害研究,将是城市气象灾害研究中的新兴领域,中国未来城市气象灾害研究也需要引起更多关注。 相似文献
7.
For the first time in history, the majority of the world population now lives in cities. Global urbanization will continue at high speed; the world's urban population is projected to increase by more than 3 billion people between 2010 and 2050. Some of this increase will be the result of high urban fertility rates and reclassification of rural land into urban areas, but a significant portion of future urbanization will be caused by rural-to-urban migration. This migration is expected to be particularly prevalent in countries and regions most affected by the changing climate. While urban populations generally enjoy a higher quality of life, many cities in the developing world have large slums with populations that are largely excluded from access to resources, jobs, and public services. In the environmental security literature, great rural resource scarcity, causing rural to urban migration, is seen as an important source of violent conflict. This study investigates how population growth affects patterns of public unrest in urban centers within the context of crucial intervening factors like democracy, poverty, economic shocks. It utilizes a newly collected event dataset of urban social disturbance covering 55 major cities in Asia and Sub-Saharan Africa since 1960. The empirical analysis provides little support for the notion that high and increasing urban population pressure leads to a higher risk or frequency of social disorder. Instead, we find that urban disorder is primarily associated with a lack of consistent political institutions, economic shocks, and ongoing civil conflict. 相似文献
8.
2019年12月2日01时沈阳国家基本气象站(沈阳站)气温1 h内异常回升了6.5℃,利用常规和加密地面观测站实况、NCEP再分析及沈阳站逐小时风廓线雷达资料,从系统配置、热力学诊断、城市热岛效应等方面对此次异常升温事件成因进行精细分析。结果表明:沈阳站异常升温阶段,超低空到近地面暖脊过境造成辽宁大部分地区出现气温回升,暖脊过境是引发沈阳站午夜时分异常升温的原因之一;沈阳站位于沈阳市的东南部,当地面风为西北风时,风从温度相对较高的城区吹向郊区,造成沈阳南部郊区各站气温回升,与北部郊区对比得出升温幅度约为3—4℃。城市热岛中心向下风方漂移是沈阳站气温骤升又一原因。值得注意的是,气温回升前的温度基础值对气温回升幅度存在一定程度影响,回升前的基础温度越低,则回升后造成的升温幅度越大。 相似文献
9.
The association between heat waves and the urban heat island effect can increase the impact on environment and society inducing biophysical hazards. Heat stress and their associated public health problems are among the most frequent. This paper explores the heat waves impact on surface urban heat island and on the local economy loss during three heat periods in Cluj-Napoca city in the summer of 2015. The heat wave events were identified based on daily maximum temperature, and they were divided into three classes considering the intensity threshold: moderate heat waves (daily maximum temperature exceeding the 90th percentile), severe heat waves (daily maximum temperature over the 95th percentile), and extremely severe heat waves (daily maximum temperature exceeding the 98th percentile). The minimum length of an event was of minimum three consecutive days. The surface urban heat island was detected based on land surface temperature derived from Landsat 8 thermal infrared data, while the economic impact was estimated based on data on work force structure and work productivity in Cluj-Napoca derived from the data released by Eurostat, National Bank of Romania, and National Institute of Statistics. The results indicate that the intensity and spatial extension of surface urban heat island could be governed by the magnitude of the heat wave event, but due to the low number of satellite images available, we should consider this information only as preliminary results. Thermal infrared remote sensing has proven to be a very efficient method to study surface urban heat island, due to the fact that the synoptic conditions associated with heat wave events usually favor cloud free image. The resolution of the OLI_TIRS sensor provided good results for a mid-extension city, but the low revisiting time is still a drawback. The potential economic loss was calculated for the working days during heat waves and the estimated loss reached more than 2.5 mil. EUR for each heat wave day at city scale, cumulating more than 38 mil. EUR for the three cases considered. 相似文献
10.
11.
Observational and model evidence of global emergence of permanent, unprecedented heat in the 20th and 21st centuries 总被引：2，自引：0，他引：2
Given the severe impacts of extreme heat on natural and human systems, we attempt to quantify the likelihood that rising greenhouse gas concentrations will result in a new, permanent heat regime in which the coolest warm-season of the 21(st) century is hotter than the hottest warm-season of the late 20(th) century. Our analyses of global climate model experiments and observational data reveal that many areas of the globe are likely to permanently move into such a climate space over the next four decades, should greenhouse gas concentrations continue to increase. In contrast to the common perception that high-latitude areas face the most accelerated response to global warming, our results demonstrate that in fact tropical areas exhibit the most immediate and robust emergence of unprecedented heat, with many tropical areas exhibiting a 50% likelihood of permanently moving into a novel seasonal heat regime in the next two decades. We also find that global climate models are able to capture the observed intensification of seasonal hot conditions, increasing confidence in the projection of imminent, permanent emergence of unprecedented heat. 相似文献
12.
Jan-Ludolf Merkens Daniel Lincke Jochen Hinkel Sally Brown Athanasios Thomas Vafeidis 《Climatic change》2018,151(3-4):413-426
Large-area coastal exposure and impact analysis has focussed on using sea-level rise (SLR) scenarios and has placed little emphasis on socioeconomic scenarios, while neglecting spatial variations of population dynamics. We use the Dynamic Interactive Vulnerability Assessment (DIVA) Framework to assess the population exposed to 1 in 100-year coastal flood events under different population scenarios, that are consistent with the shared socioeconomic pathways (SSPs); and different SLR scenarios, derived from the representative concentration pathways (RCPs); and analyse the effect of accounting for regionalised population dynamics on population exposure until 2100. In a reference approach, we use homogeneous population growth on national level. In the regionalisation approaches, we test existing spatially explicit projections that also account for urbanisation, coastal migration and urban sprawl. Our results show that projected global exposure in 2100 ranges from 100 million to 260 million, depending on the combination of SLR and population scenarios and method used for regionalising the population projections. The assessed exposure based on the regionalised approaches is higher than that derived from the reference approach by up to 60 million people (39%). Accounting for urbanisation and coastal migration leads to an increase in exposure, whereas considering urban sprawl leads to lower exposure. Differences between the reference and the regionalised approaches increase with higher SLR. The regionalised approaches show highest exposure under SSP5 over most of the twenty-first century, although total population in SSP5 is the second lowest overall. All methods project the largest absolute growth in exposure for Asia and relative growth for Africa. 相似文献
13.
Trade, transport, and sinks extend the carbon dioxide responsibility of countries: An editorial essay 总被引：2，自引：0，他引：2
Glen P. Peters Gregg Marland Edgar G. Hertwich Laura Saikku Aapo Rautiainen Pekka E. Kauppi 《Climatic change》2009,93(3-4):379-388
Sea-level rise (SLR) due to climate change is a serious global threat: The scientific evidence is now overwhelming. Continued growth of greenhouse gas emissions and associated global warming could well promote SLR of 1 m in this century, and unexpectedly rapid breakup of the Greenland and West Antarctic ice sheets might produce a 3–5 m SLR. In this paper, we assess the consequences of continued SLR for 84 coastal developing countries. Geographic Information System (GIS) software has been used to overlay the best available, spatially disaggregated global data on critical impact elements (land, population, agriculture, urban extent, wetlands, and GDP), with the inundation zones projected for 1–5 m SLR. Our results reveal that tens of millions of people in the developing world are likely to be displaced by SLR within this century; and accompanying economic and ecological damage will be severe for many. At the country level results are extremely skewed, with severe impacts limited to a relatively small number of countries. 相似文献
14.
Tobias Lung Carlo Lavalle Roland Hiederer Alessandro Dosio Laurens M. Bouwer 《Global Environmental Change》2013,23(2):522-536
To better prioritise adaptation strategies to a changing climate that are currently being developed, there is a need for quantitative regional level assessments that are systematic and comparable across multiple weather hazards. This study presents an indicator-based impact assessment framework at NUTS-2 level for the European Union that quantifies potential regional changes in weather-related hazards: heat stress in relation to human health, river flood risk, and forest fire risk. This is done by comparing the current (baseline) situation with two future time periods, 2011–2040 and 2041–2070. The indicator values for the baseline period are validated against observed impact data. For each hazard, the method integrates outcomes of a set of coherent high-resolution regional climate models from the ENSEMBLES project based on the SRES A1B emission scenario, with current and projected non-climatic drivers of risk, such as land use and socio-economic change. An index of regional adaptive capacity has been developed and compared with overall hazard impact in order to identify the potentially most vulnerable regions in Europe. The results show strongest increases in impacts for heat stress, followed by forest fire risk, while for flood risk the sign and magnitude of change vary across regions. A major difference with previous studies is that heat stress risk could increase most in central Europe, which is due to the ageing population there. An overall assessment combining the three hazards shows a clear trend towards increasing impact from climaterelated natural hazards for most parts of Europe, but hotspot regions are found in eastern and southern Europe due to their low adaptive capacities. This spatially explicit assessment can serve as a basis for discussing climate adaptation mainstreaming, and priorities for regional development in the EU. 相似文献
15.
This paper examines how international population movements from highly developed to less developed countries spread environmentally-impactful consumption habits around the world. Lifestyle migration, a phenomenon whereby relatively privileged migrants move in search of a more fulfilling life, is increasingly common around the world and serves as an optimal example for studying the spread of unsustainable consumption. We wonder whether lifestyle migrants take high consumption lifestyles typical in their countries of origin to their destination places and whether their presence in destination communities increases consumption among natives as well. This study investigates these relationships based on the case of Costa Rica, a well-established recipient country for lifestyle migration. We analyze 100% sample microdata from the Costa Rican Census 2011 to test relationships between lifestyle migration and consumption of energy-intensive goods using multilevel models that nest consumption at the household level within communities. Our findings suggest that lifestyle migrants not only consume more energy-intensive goods than native Costa Ricans, but that their presence elevates consumption among native neighbors as well. Thus, lifestyle migration may increasingly serve as a mechanism through which unsustainable consumption patterns are transferred from the Global North to the Global South. 相似文献
16.
The Finite Pool of Worry (FPW) hypothesis states that humans have finite emotional resources for worry, so that when we become more worried about one threat, worry about other threats decreases. Despite its relevance, no conclusive empirical evidence for the hypothesis exists. We leverage the sudden onset of new worries introduced by the COVID-19 pandemic as a natural experiment to test the FPW hypothesis and a related hypothesis, the Finite Pool of Attention (FPA) hypothesis. The FPA hypothesis proposes that when we pay more attention to one threat, our attention to other threats decreases. To test these two hypotheses, we assessed self-reported attention, self-reported worries, and Twitter/news attention to various threats (climate change, terrorism, economic problems, and others) throughout the pandemic in three countries (USA, Italy, and China). We find that as attention to and worry about COVID-19 increases, attention to climate change decreases, but worry does not. Our results are confirmed by further analysis of a large, longitudinal U.S. sample. We find that public perceptions that COVID-19 and climate change are related do not fully explain the positive relationship in worry between the two hazards. In summary, our findings suggest that while there may be a Finite Pool of Attention to threats, there is limited evidence for a Finite Pool of Worry. 相似文献
17.
利用2001—2010年覆盖安徽省的MODIS数据,选取在气候、地理、城市化等方面具有代表性的合肥、芜湖、阜阳作为研究对象,并结合GIS技术,分析地表温度的日变化及季节变化特征,得到安徽省代表城市热岛效应的时空分布。结果表明:安徽省省会合肥的热岛效应最为显著,安徽省南部代表城市芜湖的热岛效应强于北部代表城市阜阳, 同时具有显著的日变化和季节变化特征。近10年来,安徽代表城市热岛面积和热岛强度均呈增加趋势,但合肥热岛强度大于3 ℃的极端热岛效应有一定缓解。白天大片水体对缓解城市的热岛效应作用明显,而夜晚则不明显,甚至成为地表温度的高值中心。夏季地表温度与归一化植被指数的负相关最显著,即提高城市植被覆盖度对降低地表温度和缓解城市热岛效应有重要影响。 相似文献
18.
Urban impacts on precipitation 总被引：4，自引：0，他引：4
Ji-Young Han Jong-Jin Baik Hyunho Lee 《Asia-Pacific Journal of Atmospheric Sciences》2014,50(1):17-30
Weather and climate changes caused by human activities (e.g., greenhouse gas emissions, deforestation, and urbanization) have received much attention because of their impacts on human lives as well as scientific interests. The detection, understanding, and future projection of weather and climate changes due to urbanization are important subjects in the discipline of urban meteorology and climatology. This article reviews urban impacts on precipitation. Observational studies of changes in convective phenomena over and around cities are reviewed, with focus on precipitation enhancement downwind of cities. The proposed causative factors (urban heat island, large surface roughness, and higher aerosol concentration) and mechanisms of urban-induced and/or urban-modified precipitation are then reviewed and discussed, with focus on downwind precipitation enhancement. A universal mechanism of urban-induced precipitation is made through a thorough literature review and is as follows. The urban heat island produces updrafts on the leeward or downwind side of cities, and the urban heat island-induced updrafts initiate moist convection under favorable thermodynamic conditions, thus leading to surface precipitation. Surface precipitation is likely to further increase under higher aerosol concentrations if the air humidity is high and deep and strong convection occurs. It is not likely that larger urban surface roughness plays a major role in urbaninduced precipitation. Larger urban surface roughness can, however, disrupt or bifurcate precipitating convective systems formed outside cities while passing over the cities. Such urban-modified precipitating systems can either increase or decrease precipitation over and/or downwind of cities. Much effort is needed for in-depth or new understanding of urban precipitation anomalies, which includes local and regional modeling studies using advanced numerical models and analysis studies of long-term radar data. 相似文献
19.
Individual mobility – moving between and within different geographic regions – represents an adaptation strategy of natural resource users worldwide to cope with sudden and gradual changes in resource abundances. This work traces the recent history of Peruvian small-scale fishers’ migration, and particularly analyses the spatial mobility patterns of resource users along the Peruvian coastline in the aftermath of the coastal El Niño 2017. In February-March 2017, this event caused extraordinary heavy rains and a rise in water temperatures along the coast of northern Peru, inducing negative consequences for the small-scale fisheries and scallop (Argopecten purpuratus) aquaculture sectors, both representing important socio-economic activities in the region. Responses of local resource users to these changes were highly diverse, with a great number of people leaving the region in search for work in fishing and non-fishing activities. With a particular emphasis on the province of Sechura, this work attempts to shed light on how and why migration flows differ for fishers and scallop farmers and to explore future pathways in the context of post-disturbance recovery. About one year after the disturbance event, the small-scale fishery operated almost on a regular scale, while the aquaculture sector still struggled towards pre-El Niño conditions, reflected, for example, in a higher percentage of persons engaging in other economic activities within and outside the region. The results of this study demonstrate the importance of human movement and translocal social networks emerging in moments of crisis and should be considered for future development of long-term management strategies incorporating increasing interconnectedness of places on different scales in the face of future disturbance events. Understanding adaptation strategies of resource users in this particular social-ecological setting will further serve to inform other coastal systems prone to (re-occurring) environmental change by highlighting the diversity of socio-economic and natural drivers that can stipulate mobility and affect adaptive capacity of resource users. 相似文献
20.
Joshua W. Busby Kerry H. Cook Edward K. Vizy Todd G. Smith Mesfin Bekalo 《Climatic change》2014,124(4):717-731
Given its high dependence on rainfed agriculture and its comparatively low adaptive capacity, Africa is frequently invoked as especially vulnerable to climate change. Within Africa, there is likely to be considerable variation in vulnerability to climate change both between and within countries. This paper seeks to advance the agenda of identifying the hot spots of what we term “climate security” vulnerability, areas where the confluence of vulnerabilities could put large numbers of people at risk of death from climate-related hazards. This article blends the expertise of social scientists and climate scientists. It builds on a model of composite vulnerability that incorporates four “baskets” or processes that are thought to contribute to vulnerability including: (1) physical exposure, (2) population density, (3) household and community resilience, and (4) governance and political violence. Whereas previous iterations of the model relied on historical physical exposure data of natural hazards, this paper uses results from regional model simulations of African climate in the late 20th century and mid-21st century to develop measures of extreme weather events—dry days, heat wave events, and heavy rainfall days—coupled with an indicator of low-lying coastal elevation. For the late 20th century, this mapping process reveals the most vulnerable areas are concentrated in Chad, the Democratic Republic of the Congo, Niger, Somalia, Sudan, and South Sudan, with pockets in Burkina Faso, Ethiopia, Guinea, Mauritania, and Sierra Leone. The mid 21st century projection shows more extensive vulnerability throughout the Sahel, including Burkina Faso, Chad, Mali, northern Nigeria, Niger, and across Sudan. 相似文献