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61.
Climate change is likely to drive migration from environmentally stressed areas. However quantifying short and long-term movements across large areas is challenging due to difficulties in the collection of highly spatially and temporally resolved human mobility data. In this study we use two datasets of individual mobility trajectories from six million de-identified mobile phone users in Bangladesh over three months and two years respectively. Using data collected during Cyclone Mahasen, which struck Bangladesh in May 2013, we show first how analyses based on mobile network data can describe important short-term features (hours–weeks) of human mobility during and after extreme weather events, which are extremely hard to quantify using standard survey based research. We then demonstrate how mobile data for the first time allow us to study the relationship between fundamental parameters of migration patterns on a national scale. We concurrently quantify incidence, direction, duration and seasonality of migration episodes in Bangladesh. While we show that changes in the incidence of migration episodes are highly correlated with changes in the duration of migration episodes, the correlation between in- and out-migration between areas is unexpectedly weak. The methodological framework described here provides an important addition to current methods in studies of human migration and climate change.  相似文献   
62.
Climate change is threatening global food production and could potentially exacerbate food insecurity in many parts of the world. China is the second largest maize producer. Variations in maize yields in China are likely to have major implications for food security in the world. Based on longitudinal data of 4861 households collected annually between 2004 and 2010, we assess the impact of weather variations on maize yields in the two main producing regions in China, the Northern spring maize zone and the Yellow-Huai Valley summer maize zone. We also explore the role of adaptation, by estimating the response of Chinese farmers in both regions, in particular in terms of income diversification. With the use of household and time fixed effects, our estimates relate within-household variations in household outcomes (maize yields, net income, land and input use) to within-location variations in weather conditions. Temperature, drought, wet conditions, and precipitations have detrimental effects on maize yields in the two maize zones. The impact is stronger in the Northern spring maize zone where one standard deviation in temperature and drought conditions decreases maize yields by 1.4% and 2.5%, respectively. Nonetheless, such impact does not seem to translate into a significant fall in total net income. Adaptation seems to be key in explaining such a contrast in the Northern spring maize zone where the largest impact is estimated. On the contrary, we find a lower impact in the other region, the Yellow-Huai Valley summer maize zone but such impact is likely to intensify. The lack of adaptation observed in that region results into detrimental impacts on net farm and total income. Enhancing adaptative behaviors among Chinese farmers even further is likely to be key to future food security in China and in the rest of the world.  相似文献   
63.
The capacity of a nation to address the hydrological impacts of climate change depends on the institutions through which water is governed. Inter-institutional networks that enable institutions to adapt and the factors that hinder smooth coordination are poorly understood. Using water governance in India as an example of a complex top-down bureaucratic system that requires effective networks between all key institutions, this research unravels the barriers to adaptation by combining quantitative internet data mining and qualitative analysis of interviews with representatives from twenty-six key institutions operating at the national level.Institutions' online presence shows a disconnect in the institutional discourse between climate change and water with institutions such as the Ministries of Water Resources, Earth Sciences and Agriculture, indicating a lesser involvement compared to institutions such as the Ministries of Finance, External Affairs, Planning Commission. The online documents also indicate a more centralised inter-institutional network, emanating from or pointing to a few key institutions including the Planning Commission and Ministry of Environment and Forests. However, the interviews suggest more complex relational dynamics between institutions and also demonstrate a gap between the aspirational ideals of the National Water Mission under the National Action Plan on Climate Change and the realities of climate change adaptation. This arises from institutional barriers, including lengthy bureaucratic processes and systemic failures, that hinder effective inter-institutional networks to facilitate adaptation. The study provides new understanding of the involvement and barriers of complex multi-layered institutions in climate change adaptation.  相似文献   
64.
The past decade has seen a proliferation of community-scale climate change vulnerability assessments globally. Much of this work has employed frameworks informed by scholarship in the vulnerability field, which draws upon interviews with community members to identify and characterize climatic risks and adaptive responses. This scholarship has developed a baseline understanding of vulnerability in specific places and industries at particular times. However, given the dynamic nature of vulnerability new methodologies are needed to generate insights on how climate change is experienced and responded to over time. Longitudinal approaches have long been used in sociology and the health sciences to capture the dynamism of human processes, but their penetration into vulnerability research has been limited. In this article, we describe the application of two longitudinal approaches, cohort and trend studies, in climate change vulnerability assessment by analyzing three case studies from the Arctic where the authors applied these approaches. These case studies highlight how longitudinal approaches can be operationalized to capture the dynamism of vulnerability by identifying climate anomalies and trends, and how adaptations develop over time, including insights on themes such as social learning and adaptive pathways.  相似文献   
65.
Policy efforts to address climate change are increasingly focused on adaptation, understood as adjustments in human systems to moderate the harm, or exploit beneficial opportunities, related to actual or expected climate impacts. We examine individual-level determinants of support for climate adaptation policies, focusing on whether individuals’ exposure to extreme weather events is associated with their support for climate adaptation policies. Using novel public opinion data on support for a range of adaptation policies, coupled with high resolution geographic data on extreme weather events, we find that individuals experiencing recent extreme weather activity are more likely to support climate change adaptation policy in general, but that the relationship is modest, inconsistent across specific adaptation policies, and diminishes with time. The data thus suggest that experiencing more severe weather may not appreciably increase support for climate adaptation policies.  相似文献   
66.
Effective climate policy will consist of mitigation and adaptation implemented simultaneously in a policy portfolio to reduce the risks of climate change. Previous studies of the tradeoffs between mitigation and adaptation have implicitly framed the problem deterministically, choosing the optimal paths for all time. Because climate change is a long-term problem with significant uncertainties and opportunities to learn and revise, critical tradeoffs between mitigation and adaptation in the near-term have not been considered. We propose a new framework for considering the portfolio of mitigation and adaptation that explicitly treats the problem as a multi-stage decision under uncertainty. In this context, there are additional benefits to near-term investments if they reduce uncertainty and lead to improved future decisions. Two particular features are fundamental to understanding the relevant tradeoffs between mitigation and adaptation: (1) strategy dynamics over time in reducing climate damages, and (2) strategy dynamics under uncertainty and potential for learning. Our framework strengthens the argument for disaggregating adaption as has been proposed by others. We present three stylized classes of adaptation investment types as a conceptual framework: short-lived “flow” spending, committed “stock” investment, and lower capacity “option” stock with the capability of future upgrading. In the context of sequential decision under uncertainty, these subtypes of adaptation have important tradeoffs among them and with mitigation. We argue that given the large policy uncertainty that we face currently, explicitly considering adaptation “option” investments is a valuable component of a near-term policy response that can balance between the flexible flow and committed stock approaches, as it allows for the delay of costly stock investments while at the same time allowing for lower-cost risk management of future damages.  相似文献   
67.
Despite improvements in disaster risk management in the United States, a trend toward increasing economic losses from extreme weather events has been observed. This trend has been attributed to growth in socioeconomic exposure to extremes, a process characterized by strong path dependence. To understand the influence of path dependence on past and future losses, an index of potential socioeconomic exposure was developed at the U.S. county level based upon population size and inflation-adjusted wealth proxies. Since 1960, exposure has increased preferentially in the U.S. Southeast (particularly coastal and urban counties) and Southwest relative to the Great Plains and Northeast. Projected changes in exposure from 2009 to 2054 based upon scenarios of future demographic and economic change suggest a long-term commitment to increasing, but spatially heterogeneous, exposure to extremes, independent of climate change. The implications of this path dependence are examined in the context of several natural hazards. Using methods previously reported in the literature, annualized county-level losses from 1960 to 2008 for five climate-related natural hazards were normalized to 2009 values and then scaled based upon projected changes in exposure and two different estimates of the exposure elasticity of losses. Results indicate that losses from extreme events will grow by a factor of 1.3–1.7 and 1.8–3.9 by 2025 and 2050, respectively, with the exposure elasticity representing a major source of uncertainty. The implications of increasing physical vulnerability to extreme weather events for investments in disaster risk management are ultimately contingent upon the normative values of societal actors.  相似文献   
68.
Climate change adaptation, which has previously been seen as a national and local matter, is today systematically addressed by international institutions such as the UNFCCC, the FAO and the WTO. Research has focused on the overarching institutional architecture of global adaptation, particularly how it relates to development, political economy, efficiency and equity. In contrast to the transnational dimension of climate mitigation, the transnationalization of adaptation governance has received scant attention. By creating a dataset of adaptation projects, we examine transnational adaptation governance in terms of its scope, institutionalization and main functions. We find transnational adaptation governance to be firmly anchored within the UNFCCC, but a recent change towards adaptation governed by a transnational constituency can be identified. When non-state actors become integral to the project of governing adaptation, a ‘fourth era’ of adaption seems to be emerging. This new era is not replacing other forms of governing, but is emerging alongside and in a complementary fashion. In the ‘fourth era’, adaptation is increasingly governed globally and transnationally, and the attention is turned toward ‘softer’ forms of governance such as agenda setting, information sharing and capacity building.  相似文献   
69.
In economically marginal rural areas, choice in livelihood strategy such as decisions to move location mediates levels of individual and household resilience under conditions of environmental change. It is widely recognised that endowments associated with mobility and the entitlement to mobility are unevenly distributed across populations. This paper integrates these insights and conceptualises location choice as a set of mobility endowments and mobility entitlements. Through focussing on endowments and entitlements, the paper explores how choice affects the ability to be mobile and its role in mediating levels of resilience to livelihood shocks associated with changing environmental conditions. The research design involves measuring the impact of different climatic perturbations in rural locations in Anhui Province, China. Mixed methods of rural appraisal, life history interviews, and a household survey generate objective and perceived elements of individual and household responses to risks. These data are augmented by biophysical observations on the nature of the climatic perturbations. The results show that mobility endowments and mobility entitlements are important in determining the impact of mobility on resilience. The life history interview data highlight significant individual agency within the structures that impact on individual choices. Further, individuals and households who possess the ability to decide and to subsequently enact decisions about mobility, are shown to be more resilient compared to other individuals and households that lack such ability. Moreover, households practicing short-term, circular mobility are more resilient than those households that practice long-term mobility. The study confirms that, in these instances, choice and the ability to enact those choices mediates resilience and highlights the implications of location decisions but also the conditions in which those decisions are made.  相似文献   
70.
This article uses a governmentality perspective to uncover the power effects of the external climate change adaptation assistance provided by the European Union (EU) through its flagship initiative in this regard: the Global Climate Change Alliance. By drawing upon a body of literature that conceptualizes the established international architecture in this regard as rooted in power relations, this article opens up our current perspective of the EU as an international climate actor. An analysis of policy documents and targeted semi-structured interviews reveals that the EU discursively emphasizes the responsibility of partner countries to manage risk and become ‘resilient’ to climate impacts, while downplaying the transformative potential of adaptation for development. We see this dynamic further reflected in GCCA policy techniques, which promote the production of quantified and depoliticized knowledge on adaptation. This in its turn further guides the allocation of GCCA support and is instrumentalized in order to establish a stable identity for the organization and reproduce the EU as a climate leader in this regard.  相似文献   
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