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71.
土壤湿度是控制陆地和大气间水热能量交换的一个关键参数,同时也是陆面生态系统水循环的重要组成部分。本文选用25 km分辨率的CCI(Climate Change Initiative)土壤湿度产品数据,并结合1 km分辨率的MODIS数据,构建微波土壤湿度产品数据降尺度回归算法,获取淮河流域1 km空间分辨率的土壤湿度数据。降尺度后所获取淮河流域1 km空间分辨率的土壤湿度数据总体上提高了25 km空间分辨率的CCI土壤湿度产品数据的精度.  相似文献   
72.
我国城市规划中气候信息应用回顾与展望   总被引:2,自引:1,他引:1  
城市规划中气候信息的应用经历了从早期的风玫瑰图利用到考虑风、温、湿、压等要素的气候适宜性分析以及目前关注城市通风环境、热环境以及污染敏感区的城市环境气候图技术的历程。气候信息获得的途径也从数量极为有限的基本气象观测站资料到空间加密的自动气象站资料、更精细的气象数值模式以及精细化地理信息技术的应用。同时,细化的技术导则和规范的建立以及不同行业间的联合发文有力推动了气候信息的实际应用。此外,研究展示了近年开展的伊犁、深圳、北京实际案例主要内容。最后,针对未来我国将根据大气环流特征和生态环境承载能力、走优化城镇空间布局和城镇规模结构的新型城镇化道路,从工作层面和技术层面给出了需要不断完善并深入研究的几个重点。  相似文献   
73.
The transition area of three natural zones (Eastern Monsoon Region, Arid Region of Northwest China, Qinghai Tibet Plateau Region) is influenced by the Asian monsoon and middle latitude westerly circulation because of its special geographical position. And it is more sensitive to global climate change. The Koppen climate classification, which is widely used in the world, and the accumulated temperature-dryness classification, which is usually used in China, were used to study the climate zones and changes in the region of longitude 97.5°~108°E, latitude 33°~41.5°N, from 1961 to 2010. The changing areas of each climate zone were compared to the East Asian Summer Monsoon index, the South Asian Summer Monsoon index, the Summer Westerly index, the East Asian Winter Monsoon index, the Plateau Summer Monsoon index, the North Atlantic Oscillation index, the Southern Oscillation index, NINO3.4 index, to explore the response of the transition area of three natural zones to each climate system. According to the results, this region will become wetter when the Summer Westerly or the East Asian Winter Monsoon is relatively strong. When the East Asian Summer Monsoon or the South Asian Summer Monsoon becomes strong, the climate in low altitude region of the study area will easily become drier, and the climate in high altitude region of the study area is easily to become wetter. When the Plateau Summer Monsoon is relatively strong, the climate in the study area will easily become drier. When the North Atlantic Oscillation is relatively strong, the study area will easily become wetter. And when the El Niño is relatively strong, or the Southern Oscillation is relatively weak, the study area will easily become drier. In general, the moisture status of this region is mainly controlled by the middle latitude westerly circulation. The enhancement of the Asian summer monsoon could increase the precipitation in the southeast part of this regional, but, according to the degrees of dryness and the types of climate change in this paper, warming effects could offset precipitation increasing and make the area drier. The transition area of three natural zones is influenced by multiple interactions of climate systems from East Asia. A single climatic index, such as air temperature or precipitation, can not completely represent the regional features of climate change. As a result, areas of climate zones can be used as an important index in the regional climate change assessment.  相似文献   
74.
The international climate change negotiation has been carried out over 20 years. The issue of climate change has shifted from a scientific question into a complex political matter which is related to the sustainable development of mankind. Based on the overview of major processes and stages of international climate conferences, this paper analyzed the key measures that major countries have taken to address climate change, as well as the primary tasks of Paris climate conference and recent international actions. The recent international climate policy issues were also analyzed in order to provide suggestions for China’s activel participation in the development of a new round of international climate change system.  相似文献   
75.
Studying climate changes over the past 2 000 years has important scientific significance in exploring climate variability on decadal to centennial timescales, assessing the natural and anthropogenic contribution to the climate warming, and understanding the effects of human activities in the past and future climate changes. Due to the scarcity of observation and uncertainty of reconstruction in this period, climate model is developed as a useful tool for studying paleoclimate.The Community Earth System Model (CESM) is one of the state-of-the-art climate models, but its performance in simulating the temperature in China has not been examined.The temperature datasets of observation/reanalysis (GHCN_CAMS) and reconstructions during the past 2000 years in China were used to examine the performance of CESM. The comparison between the annual average temperatures of GHCN_CAMS reanalysis and simulation showed that the model well reproduced the spatial distributions and upward trend of the annual average temperature in China, and the comparison with reconstructions in five sub-regions of China indicated that the simulation were in good consistent with the average temperature changes of reconstructionson decadal time scales. On the centennial time scale, the average temperature fluctuations of simulation in the regions of China were in accord with reconstructions generally except for Central East and Tibet.There existed three warm periods of simulated temperature variation in China over the past 2000 years, including 0-540AD, 800-1250AD and 1901-2000AD, and two cold periods involving the 551-721AD and 1400-1850AD, which had some discrepancies with reconstructions. And the discrepancies between simulation and reconstructions might be related to uncertainties of the resolution, external forcing and parameterization of the subgrid-scale process in the model.  相似文献   
76.
77.
In this intervention article I contribute to discussions of moral economy by arguing that scholars should reconsider the nature of value. Neoliberalism considers only exchange value. As a consequence neoliberal policies try to manage problems such as climate change with economic systems and instruments that are mis-calibrated to the material realities they are meant to represent. Value has spatial and temporal characteristics. Recognizing the spatial and temporal dynamics of value leads to new means of resource valuation, such as extending the time-frame of instruments and changing the nature of privatization. In conclusion, I argue for the need for new theories of use value.  相似文献   
78.
79.
In a 2004 special issue of Geoforum, McCarthy and Prudham argued that the connections between neoliberalism and the environment had been underexplored in critical scholarship. In an attempt to address this gap, the special issue reflected on a number of different case studies and set the stage for a decade of analysis and critique. This paper aims to contribute to the increasing body of literature by presenting a detailed theoretical analysis of neoliberal environmentalism and its role in modern society. Specifically, the paper focuses on one particular environmental issue – climate change – and uses it to categorise six discourses that either conform to the principles of neoliberalism (reformist) or reject neoliberal ideas (revolutionary). Drawing on interviews with designated ‘climate champions’ (individuals who are given responsibility for promoting climate protecting behaviour) in large corporations, the paper then demonstrates how this kind of typological framework might be applied to the analysis of neoliberal environmentalism in the ‘real world’. The paper finds that neoliberalism played a very influential role in the promotion of climate protecting behaviour in the workplace. However, there was also some limited evidence of resistance in the form of revolutionary discourses and ideas. Going forwards, the typological framework may provide a valuable analytical tool to assess the dominance and resistance of neoliberal environmentalism in the modern world.  相似文献   
80.
What is the relationship between the direction and form of an energy transition and the political economy within which it is embedded? This paper explores how the nature of (low carbon) energy transitions is strongly influenced by the process of neoliberalisation that shape energy policy in the South. We seek to understand emergent energy transitions and to advance their theorisation through an account of the political economy of energy transition in Kenya. In contrast to the often techno-managerial orientation of literatures on socio-technical transitions, we explore the political terrain upon which competing visions of energy futures and material interests collide and seek to accommodate one another. We develop a political economy account that emphasises the structural and disciplinary power of capital and global institutions to set the terms of transition. This expresses itself in both delimiting the autonomy of state actors and by reconfiguring domestic institutional and social power in ways that shape the distributional politics of transitions.  相似文献   
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