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51.
Constraining global average temperatures to 2 °C above pre-industrial levels will probably require global energy system emissions to be halved by 2050 and complete decarbonization by 2100. In the nationally orientated climate policy framework codified under the Paris Agreement, each nation must decide the scale and method of their emissions reduction contribution while remaining consistent with the global carbon budget. This policy process will require engagement amongst a wide range of stakeholders who have very different visions for the physical implementation of deep decarbonization. The Deep Decarbonization Pathways Project (DDPP) has developed a methodology, building on the energy, climate and economics literature, to structure these debates based on the following principles: country-scale analysis to capture specific physical, economic and political circumstances to maximize policy relevance, a long-term perspective to harmonize short-term decisions with the long-term objective and detailed sectoral analysis with transparent representation of emissions drivers through a common accounting framework or ‘dashboard’. These principles are operationalized in the creation of deep decarbonization pathways (DDPs), which involve technically detailed, sector-by-sector maps of each country’s decarbonization transition, backcasting feasible pathways from 2050 end points. This article shows how the sixteen DDPP country teams, covering 74% of global energy system emissions, used this method to collectively restrain emissions to a level consistent with the 2 °C target while maintaining development aspirations and reflecting national circumstances, mainly through efficiency, decarbonization of energy carriers (e.g. electricity, hydrogen, biofuels and synthetic gas) and switching to these carriers. The cross-cutting analysis of country scenarios reveals important enabling conditions for the transformation, pertaining to technology research and development, investment, trade and global and national policies.

Policy relevance

In the nation-focused global climate policy framework codified in the Paris Agreement, the purpose of the DDPP and DDPs is to provide a common method by which global and national governments, business, civil society and researchers in each country can communicate, compare and debate differing concrete visions for deep decarbonization in order to underpin the necessary societal and political consensus to design and implement short-term policy packages that are consistent with long-term global decarbonization.  相似文献   
52.
This article assesses Japan's carbon budgets up to 2100 in the global efforts to achieve the 2?°C target under different effort-sharing approaches based on long-term GHG mitigation scenarios published in 13 studies. The article also presents exemplary emission trajectories for Japan to stay within the calculated budget.

The literature data allow for an in-depth analysis of four effort-sharing categories. For a 450?ppm CO2e stabilization level, the remaining carbon budgets for 2014–2100 were negative for the effort-sharing category that emphasizes historical responsibility and capability. For the other three, including the reference ‘Cost-effectiveness’ category, which showed the highest budget range among all categories, the calculated remaining budgets (20th and 80th percentile ranges) would run out in 21–29 years if the current emission levels were to continue. A 550?ppm CO2e stabilization level increases the budgets by 6–17 years-equivalent of the current emissions, depending on the effort-sharing category. Exemplary emissions trajectories staying within the calculated budgets were also analysed for ‘Equality’, ‘Staged’ and ‘Cost-effectiveness’ categories. For a 450?ppm CO2e stabilization level, Japan's GHG emissions would need to phase out sometime between 2045 and 2080, and the emission reductions in 2030 would be at least 16–29% below 1990 levels even for the most lenient ‘Cost-effectiveness’ category, and 29–36% for the ‘Equality’ category. The start year for accelerated emissions reductions and the emissions convergence level in the long term have major impact on the emissions reduction rates that need to be achieved, particularly in the case of smaller budgets.

Policy relevance

In previous climate mitigation target formulation processes for 2020 and 2030 in Japan, neither equity principles nor long-term management of cumulative GHG emissions was at the centre of discussion. This article quantitatively assesses how much more GHGs Japan can emit by 2100 to achieve the 2?°C target in light of different effort-sharing approaches, and how Japan's GHG emissions can be managed up to 2100. The long-term implications of recent energy policy developments following the Fukushima nuclear disaster for the calculated carbon budgets are also discussed.  相似文献   
53.
探索新型测绘的产生背景与科学内涵等问题,对新时期测绘地理信息事业转型升级与跨越发展具有重要意义。该文首先从经济社会发展需求、测绘发展新阶段、测绘地理信息转型升级、测绘地理信息跨越发展4个方面阐述了新型测绘产生的背景;其次,从新型测绘关系角度给出了新型测绘的内涵与架构,从范围、内容、技术手段、体制机制方面描述了新型测绘的特征;再次,从新型测绘目标出发,描述了新型基础测绘的内涵、要求与主要任务,地理国情监测的总体目标与主要任务,公共服务与应急测绘的新需求与主要任务;最后围绕测绘地理空间数据获取、处理、管理、分析、服务与应用主线,探讨了新型测绘需要着重研究的新理论、新方法、新技术装备,旨在为新型测绘的研究与发展奠定基础。  相似文献   
54.
Abstract

This article applies open source data of public facilities through data mining, not only to evaluate the public facilities from an objective dimension, but also to reflect the sensory opinions of the group factually, eventually realizing the evaluation measurement of urban public facilities. The research takes Shenzhen city as an empirical case and chooses typical public facilities to mine data, resolve address and weight to explore the application of public facilities evaluation under dimension reduction of open source data. The empirical study consists of three parts. First, as the objective evaluation, we estimate the density distribution and per capita of public facility through data mining and address resolution. Second, as the subjective evaluation, we carry on the location analysis to high-score public facility through attention and satisfaction data of Internet evaluation. Finally, as mentioned above, we calculate the weight of objective and subjective evaluation of public facility, eventually formatting the comprehensive evaluation of public facilities.  相似文献   
55.
In a global context of promotion and expansion of blue growth initiatives, the development of activities such as aquaculture calls for the assessment of the potential impacts on biodiversity at different levels and associated services. This paper presents an assessment of the potential impact of the installation of seaweed farms on ecosystem services and the induced compensation costs. Biophysical and socioeconomic indicators have been developed for helping decision makers to select the most suitable locations. The approach considers a multi-criteria approach based on Geographical Information Systems (GIS) and Habitat Equivalency Analysis (HEA). The former is used to obtain biophysical ecosystem services and socioeconomic indicators and the latter to evaluate the costs required to compensate the loss of cultural and provisioning ecosystem services. A case-study in the Normand-Breton (Saint Malo) Gulf, France, illustrates this method through the analysis of hypothetical locations of seaweed farms. Results highlight the differences between alternative locations regarding biophysical constraints (in terms of distance and depth), potential risks of conflicts with existing uses, impacts on habitats and the ecosystem services delivered, and compensation costs. This case-study illustrates the flexibility of this approach which can be further adapted to include other indicators in order to deliver integrated information to coastal planners.  相似文献   
56.
Public service systems, such as emergency health care, police or fire brigades, are critical for day-to-day functioning of the society. To design and operate these systems efficiently much data needs to be collected and properly utilised. Here, we use the OpenStreetMap (OSM) data to model the demand points (DPs), which approximate the geographical location of customers, and the road network, which is used to access or distribute services. We consider all inhabitants as customers, and therefore to estimate the demand, we use the available population grids. People are changing their location in the course of the day and thus the demand for services is changing accordingly. In this paper, we investigate how the used demand estimate affects the optimal design of a public service system. We calculate and compare efficient designs corresponding to two demand models, a night-time demand model when the majority of inhabitants rest at home and the demand model derived from the 24-hour average of the population density. We propose a simple measure to quantify the differences between population grids and we estimate how the size of differences affects the optimal structure of a public service system. Our analyses reveal that the efficiency of the service system is not only dependent on the placement strategy, but an inappropriate demand model has significant effects when designing a system as well as when evaluating its efficiency.  相似文献   
57.
《Comptes Rendus Geoscience》2018,350(7):435-441
Many observers and commentators have used the case of ozone science and politics as a role model for climate science and politics. Two crucial assumptions underpin this view: (1) that science drives policymaking, and (2) that a unified, international science assessment is essential to provide “one voice” of science that speaks to policymakers. I will argue that these assumptions are theoretically problematic and empirically questionable. We should realize that both cases, ozone and climate, are profoundly different and only have superficial similarities. Ozone science developed late, but efforts to protect the ozone layer happened swiftly. The relation between carbon dioxide and climate change has been studied for many decades, but efforts to control global warming have failed so far. I will discuss the linear model of the science-policy relationship and use the typology of tame and wicked problems to explain this stark difference.  相似文献   
58.
The majority of emissions of nitrous oxide – a potent greenhouse gas (GHG) – are from agricultural sources, particularly nitrogen fertilizer applications. A growing focus on these emission sources has led to the development in the United States of GHG offset protocols that could enable payment to farmers for reducing fertilizer use or implementing other nitrogen management strategies. Despite the development of several protocols, the current regional scope is narrow, adoption by farmers is low, and policy implementation of protocols has a significant time lag. Here we utilize existing research and policy structures to propose an ‘umbrella’ approach for nitrogen management GHG emissions protocols that has the potential to streamline the policy implementation and acceptance of such protocols. We suggest that the umbrella protocol could set forth standard definitions common across multiple protocol options, and then modules could be further developed as scientific evidence advances. Modules could be developed for specific crops, regions, and practices. We identify a policy process that could facilitate this development in concert with emerging scientific research and conclude by acknowledging potential benefits and limitations of the approach.

Key policy insights

  • Agricultural greenhouse gas market options are growing, but are still underutilized

  • Streamlining protocol development through an umbrella process could enable quicker development of protocols across new crops, regions, and practices

  • Effective protocol development must not compromise best available science and should follow a rigorous pathway to ensure appropriate implementation

  相似文献   
59.
Since the Paris Agreement was adopted in 2015, both national and subnational governments have been encouraged to submit Mid-Century Strategies, outlining how they would reach their deep decarbonization goals. However, research on the design and potential of these strategies has been very limited. To address this shortcoming, here we assess 13 such strategies – six national, seven subnational – in a comparative fashion. We find that the energy-economy-climate models underpinning these strategies are generally of high quality, though national jurisdictions generally performed better. However, most strategies are not plausible without significant changes to policy, and the industrial sector in particular presents a major limitation. The strategies are helpful in revealing this gap, but much works remains to be done for plausible mid-century decarbonization trajectories to become a reality. We also find that public input and societal participation in strategy building were a double-edged sword depending on the constellation of domestic preferences.
  • Governmental Mid-Century Strategies for deep decarbonization are underpinned by high-quality energy-economy-climate models

  • Governments’ proposed strategies require significant new policies, as even among jurisdictions that have an MCS, extant policies are insufficient to achieve deep decarbonization

  • No jurisdiction studied has yet put forward a plausible decarbonization policy for the industrial sector.

  • Public input and societal participation can be a double-edged sword: they can increase durability of the strategy but also enable opposing forces to mobilize against ambitious changes.

  相似文献   
60.
Upon completion, China’s national emissions trading scheme (C-ETS) will be the largest carbon market in the world. Recent research has evaluated China’s seven pilot ETSs launched from 2013 on, and academic literature on design aspects of the C-ETS abounds. Yet little is known about the specific details of the upcoming C-ETS. This article combines currently understood details of China’s national carbon market with lessons learned in the pilot schemes as well as from the academic literature. Our review follows the taxonomy of Emissions Trading in Practice: A Handbook on Design and Implementation (Partnership for Market Readiness & International Carbon Action Partnership. (2016). Retrieved from www.worldbank.org): The 10 categories are: scope, cap, distribution of allowances, use of offsets, temporal flexibility, price predictability, compliance and oversight, stakeholder engagement and capacity building, linking, implementation and improvements.

Key policy insights

  • Accurate emissions data is paramount for both design and implementation, and its availability dictates the scope of the C-ETS.

  • The stakeholder consultative process is critical for effective design, and China is able to build on its extensive experience through the pilot ETSs.

  • Current policies and positions on intensity targets and Clean Development Mechanism (CDM) credits constrain the market design of the C-ETS.

  • Most critical is the nature of the cap. The currently discussed rate-based cap with ex post adjustment is risky. Instead, an absolute, mass-based emissions cap coupled with the conditional use of permits would allow China to maintain flexibility in the carbon market while ensuring a limit on CO2 emissions.

  相似文献   
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