控制温室效应的战略选择

尽管人类对温室效应和全球变化的认识还是很不充分的，但是继续拖延不采取措施是危险的，采取对抗温室效应和全球变化的措施是行不通的。只有在继续进行全球性科学研究的同时，积极寻求适应一定程度全球变化的措施，并立即着手减少温室气体的排放才是唯一明智的态度。化石能源是人类社会生存和发展的基础，既使用化石能源，又不排放二氧化碳是不可能是。首要的任务是减少化石能源的使用。     

THE INFLUENCE OF (x,y) UNCERTAINTY ON PREDICTION ERROR AND CONTOUR LINES FROM A THREE-DIMENSIONAL SURFACE1

ABSTRACT: In geohydrology, three-dimensional surfaces are typically represented as a series of contours. Water levels, saturated thickness, precipitation, and geological formation boundaries are a few examples of this practice. These surfaces start as point measurements that are then analyzed to interpolate between the known point measurements. This first step typically creates a raster or a set of grid points. In modeling, subsequent processing uses these to represent the shape of a surface. For display, they are usually converted to contour lines. Unfortunately, in many field applications, the (x, y) location on the earth's surface is much less confidently known than the data in the z dimension. To test the influence of (x, y) locational accuracy on z dimension point predictions and their resulting contours, a Monte Carlo study was performed on water level data from northwestern Kansas. Four levels of (x, y) uncertainty were tested ranging in accuracy from one arc degree-minute (± 2384 feet in the x dimension and ± 3036 feet in the y dimension) to Global Positioning Systems (GPS) accuracy (± 20 feet for relatively low cost systems). These span the range of common levels of locational uncertainty in data available to hydrologists in the United States. This work examines the influence that locational uncertainty can have on both point predictions and contour lines. Results indicate that overall mean error exhibits a small sensitivity to locational uncertainty. However, measures of spread and maximum errors in the z domain are greatly affected. In practical application, this implies that estimates over large regions should be asymptotically consistent. However, local errors in z can be quite large and increase with (x, y) uncertainty.     

农业病虫害的灾变预测及预报精度分析

在农业病虫害突变规律的研究基础上,建立了定性与定量的尖角突变模型,确定了各病虫的突变区域。根据综合控制变量所确定的边界值,对未来病虫发生发展趋势进行预测。经多年历史资料检验和1992年农业病虫害发生突变的趋势预报证明:准确率高,覆盖面广。     

CULTURAL ASPECTS OF WATER RESOURCE DEVELOPMENT PAST,PRESENT, AND FUTURE1

ABSTRACT Attitudes toward the development of the American West have undergone important changes over the past century just as the nature of water resources as factors in development have changed. Viewing these changes processually, stages for water resources definition and use can be identified in the total process of western cultural development. The first stage involves the value of water resource development as a stimulus to population and economic growth in the West. The second stage, still in process', adopts a dominant cultural norm which sees water resource development as inevitable if not necessary to keep up with growth. A third stage to this evolutionary process is incipient. Future cultural values and thinking with respect to water resource development will be to look at development as a means for controlling or managing both the location and quantity of population and economic growth. To this end planners will have to become concerned with the questions of human adaptation. Concern will have to be given to the problems of getting a living which enables individuals to meet the subsistence needs of self and family, to establishing community which provides for cooperation among individuals and the management of conflict, to establishing improved communication which promotes interpersonal interaction, and for fostering innovation which provides the new ideas necessary to adapt to new environmental situations.,     

A new role for citizens’ initiatives: the difficulties in co-creating institutional change in urban planning

In this paper, we analyze the institutional work that underlies the attempt to institutionalize a more active role of citizens in urban planning. We draw on a case in which a group of citizens aims to redevelop a brownfield site into a vital urban area. This citizens’ initiative is co-creating a new form of urban planning with the municipality, private organizations and individual citizens. The study shows how citizens’ initiatives can be a driver for institutional change, but that uncertainties about new institutions tend to reinforce the maintenance of existing ones. This paradox explains why even if the ambition for a new form of planning is widely shared, actually realizing institutional change can still be difficult and time-consuming.     

Exogenous factors in collective policy learning: the case of municipal flood risk governance in the Netherlands

ABSTRACT

Conceptualizing and analyzing collective policy learning processes is a major ongoing theoretical and empirical challenge. A key gap concerns the role of exogenous factors, which remains under-theorized in the policy learning literature. In this paper, we aim to advance the understanding of the role that exogenous factors play in collective learning processes. We propose a typology of exogenous factors (i.e. material, socioeconomic, institutional, discursive), and subsequently apply this in a comparative study of flood risk policymaking in two municipalities in the Netherlands. We find that exogenous factors are indeed essential for understanding collective learning in these cases, as the combined influence with endogenous factors can steer similar learning processes towards different learning products. We conclude our contribution by identifying two opportunities for further developing the collective learning framework, namely regarding the distinction of varying learning products, and the dynamics of exogenous factors over time.     

Leveraging the power of learning to overcome negotiation deadlocks in global climate governance and low carbon transitions

ABSTRACT

Learning among actors within the United Nations Framework Convention on Climate Change (UNFCCC) negotiations helped transferring climate policies across countries and changed negotiation positions. Together with group pressure and leadership by key governments and non-national actors, experience, knowledge and belief-based learning types altered the UNFCCC negotiation dynamics and facilitated the Paris Agreement. Governments, the UNFCCC secretariat and NGOs created opportunities for government representatives to explore policy options and learn from each other’ successes of designing and implementing low carbon policies. These experience exchanges during and beyond the UNFCCC meetings were established to help countries share their experiences with low carbon economic development plans to address climate change while decoupling economic growth. Based on elite interviews, participant observation and document analysis, this contribution examines how learning facilitated breakthroughs in international climate negotiations. It finds that structured experience exchange of and reflection on other countries’ and non-national actors’ successful policy experiences can modify national interests as policymakers increasingly understand that climate action can support economic growth. This resulted in a higher willingness to take on more ambitious climate action commitments. Sharing experiences with climate policies can facilitate other actor’s learning how they can adapt successful policies to their specific framework conditions.     

Monitoring Parks Through Remote Sensing: Studies in Nepal and Honduras

The effectiveness of parks as management regimes is hotly contested. Much of the current discussion centered around comparisons of management regimes can be traced to a dearth of cross-site quantitative evaluations. Remote sensing provides a particularly effective tool for this purpose, yet analysis of remotely sensed data requires fieldwork to interpret human activities and the socioeconomic and political contexts that relate to land cover change. This paper examines the effect of establishment of the Celaque National Park, Honduras, and the Royal Chitwan National Park buffer zone, Nepal, on limiting deforestation. In Celaque, the park itself has been largely successful in maintaining forest cover. However, recent changes in land use patterns have led to increasing pressure on the park boundaries, exacerbated by the lack of involvement of local residents. In the Royal Chitwan National Park, in contrast, participatory approaches towards co-management have been implemented over the past decade in the park buffer zone. With significant incomes derived from ecotourism, complete protection of the buffer zone forest has been adopted, leading to significant regrowth of tree cover. However, local decision-making power is limited, and buffer zone management has largely proven successful due to the investment and support provided by international donor agencies. These two case studies demonstrate the utility of remote sensing and Geographical Information Systems analysis in providing a spatiotemporal perspective for assessing management policies. They also demonstrate the importance of fieldwork to provide a nuanced understanding of the socioeconomic and institutional conditions affecting the outcomes of forest management regimes.     

Economic and Ecological Transformation Processes in East German Water Management Regimes: The Role of Property Rights and Governance Structures

As in many fen land regions in East Germany, long-standing intensive arable farming—enabled by reclamation—has caused soil deterioration and high water runoff in the Schraden region. The more than ten years of economic and political transformation that followed the breakdown of the socialist regime has worsened the situation and even added new problems. The visible consequences are droughts in the summer, waterlogged plots in the spring, and worn-down water management facilities that operate in an uncoordinated or even unauthorized way. Given the local public-good character of some features of the fen land, the common-pool character of the ecosystems intermittently scarce resource water, and the conflicting interests of regional stakeholders, it is argued that the reallocation of property rights over reclamation systems, together with ineffective coordination mechanisms, have caused the physical and institutional failure of the water management system and so impeded appropriate land use. Note: This version was published online in June 2005 with the cover date of August 2004.     

Energy indicators and sustainable development: The International Energy Agency approach

The International Energy Agency (IEA), together with the International Atomic Energy Agency (IAEA), UN‐DESA, Eurostat and the European Environmental Agency, has recently published a comprehensive joint‐agency overview of energy indicators for sustainable development. The IEA's contribution to this publication is based on the IEA energy indicator approach. This approach has been developed and used by the IEA over a number of years. The indicators advocated by the IEA are relatively disaggregated to allow for meaningful analysis of sustainability issues in the energy sector. Using a decomposition approach helps reveal the causal links between human/economic driving forces, energy use and emissions. This article presents examples of IEA's work with indicators and an overview of the methodology used, including an explanation of the link to sustainable development. It also provides an example of a simplified indicator analysis of India, to illustrate the importance of improved data systems in developing indicators that can provide meaningful policy analysis.