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281.
Yang  Xuhong  Jin  Xiaobin  Yang  Yongke  Song  Jiani  Zhang  Tong  Zhou  Yinkang 《地理学报(英文版)》2022,32(3):441-457
Journal of Geographical Sciences - Reconstructing long-term changes of forest cover (FC) can provide reliable underlying data for carbon source/sink accounting and simulation of the effects of land...  相似文献   
282.
For over 20 years, Parties to the UN Framework Convention on Climate Change have struggled with the normative significance of history for the differentiation of responsibilities. Negotiations on ‘historical responsibility’ have been marked by considerable conflict between developed and developing countries. However, in 2010, the Parties acknowledged the concept in a consensus decision. This article analyses UN Climate Change Conference delegates' agreement with the decision, whether it reconciled conflict between interpretations of historical responsibility, and the significance that delegates ascribe to the decision for future agreements. The decision has not eliminated conflict between different interpretations. Delegates who understand historical responsibility as linking countries' historical contributions to climate change to their responsibilities to act agree more with the decision and foresee it having a stronger influence on future agreements than do those viewing the concept in more conceptual terms. The decision marks the start of negotiations concerning how rather than whether historical responsibility should guide operative text. This article demonstrates that (1) the divergent interpretations pose clear challenges for a necessary but demanding agreement on operationalization, and (2) focusing on an ambiguous version of proportionality between contribution to change and responsibility can become a first step for convergence between divergent positions.  相似文献   
283.
《Climate Policy》2013,13(6):593-611
Following the conclusion of the official work of the Ad Hoc Group for the Modelling and Assessment of Contributions to Climate Change (MATCH), this article considers the politically more sensitive aspect of the Brazilian proposal, namely the issue of differentiating (historic) responsibility for, and not merely (causal) contribution to climate change. Its aim is (1) to highlight the fact that, while related, the two issues (‘contribution to’ and ‘responsibility for’) are fundamentally different and should not be confused, and (2) to propose a methodology for calculating shares of responsibility as opposed to the shares in causal contribution arrived at through the MATCH results. Two conceptions of responsibility (‘strict’ or ‘limited’) are applied in order to operationalize the notion of ‘respective capabilities’ given in Article 3.1 of the UNFCCC. The key message resulting from the calculations is that causal contribution—while an important indicator of (environmental) relevance to the problem—must not be confused with the moral responsibility for it. The rather large difference between the responsibilities at the two extremes of the scale under both conceptions gives pause for thought as to what sorts of burdens can justly be demanded in any application of the UNFCCC principle of common but differentiated responsibilities, whether in the context of the Brazilian proposal or beyond.  相似文献   
284.
In this paper,a multistep finite difference scheme has been proposed,whose coefficients are determined taking into consideration compatibility and generalized quadratic conservation,as well as incorporating historical observation data.The schemes have three advantages:high-order accuracy in time,generalized square conservation,and smart use of historical observations.Numerical tests based on the one-dimensional linear advection equations suggest that reasonable consideration of accuracy,square conservation,and inclusion of historical observations is critical for good performance of a finite difference scheme.  相似文献   
285.
动力-统计客观定量化汛期降水预测研究新进展   总被引:3,自引:0,他引:3       下载免费PDF全文
汛期降水预测是短期气候预测的重要内容之一,也是难点之一。近20年来,动力-统计相结合的预测方法在解决这一复杂的科学难题方面取得了一定进展。该文系统地介绍了近年来国家级气候预测业务中关于动力-统计客观定量化预测的原理、最优因子订正和异常因子订正两类预测方案,及动力-统计集成的中国季节降水预测系统 (FODAS1.0)。2009—2012年的汛期降水预测中,动力-统计客观定量化预测方法4年平均PS评分为73,距平相关系数为0.16,体现了较高的预报技巧。但该方法仍存在不足,需通过加强气候因子与降水之间关系的诊断分析、完善短期气候模式的物理过程、改进参数化方案及研发有针对性的区域气候模式等手段,进一步提高模式本身的预报技巧,使动力-统计预测方法在汛期降水预测中发挥更大作用。  相似文献   
286.
Long-term emissions scenarios have served as the primary basis for assessing future climate change and response strategies. Therefore, it is important to regularly reassess the relevance of emissions scenarios in light of changing global circumstances and compare them with long-term developments to determine if they are still plausible, considering the newest insights. Four scenario series, SA90, IS92, SRES, and RCP/SSP, were central in the scenario-based literature informing the five Assessment Reports of the Intergovernmental Panel on Climate Change (IPCC) and the sixth assessment cycle. Here we analyze the historical trends of carbon dioxide (CO2) emissions from fossil fuel combustion and industry and emissions drivers between 1960 and 2017. We then compare the emission scenario series with historical trends for the period 1990–2017/2018. The results show that historical trends are quite consistent with medium scenarios in each series. As a result, they can be regarded as valid inputs for past and future analyses of climate change and impacts. Global CO2 emissions 1960–2018 (and 1990–2018) comprised six (and three) overall subperiods of emissions growth significantly higher and lower than average. Historically, CO2 emissions (in absolute numbers and growth rate) are tightly coupled with primary energy and indirectly with GDP. Global emissions generally followed a medium-high pathway, captured by “middle-of-the-road” scenario narratives in the earlier series, and by combinations of “global-sustainability” and “middle-of-the-road” narratives in the most recent series (SRES and SSP-baselines). Historical non-OECD trends were best captured by “rapid-growth” and “regional-competition” scenarios, while OECD trends were close to regional-sustainability and global-sustainability scenarios. Areas where the emissions scenarios captured the historical trends less well, are renewable and nuclear primary energy supply. The fact that the actual historical development is consistent with rapid-growth narratives in the non-OECD regions might have important implications for future greenhouse gas emissions and associated climatic change.  相似文献   
287.
Reconstructing historical land use and land cover change (LUCC) at the regional scale is an important component of global environmental change studies and of improving global historical land use datasets. By analyzing data in historical documents, including military-oriented cropland (hereafter M-cropland) area, the number of households engaged in M-cropland (hereafter M-household) reclamation, cropland area, and the number of households, we propose a conversion relationship between M-cropland area and cropland area reclaimed by each household. A provincial cropland area estimation method for the Yuan Dynasty is described and used to reconstruct the provincial cropland area for AD1290. Major findings are as follows. (1) Both the M-cropland and cropland areas of each household were high in the north and low in the south during the Yuan Dynasty, which resulted from different natural conditions and planting practices. Based on this observation, the government-allocated M-cropland reclamation area to each household was based on the cropland area reclaimed by each household. (2) The conversion relationship between M-cropland and cropland areas per household showed conversion coefficients of 1.23 and 0.65 for the south and north, respectively. (3) The cropland area in the entire study area in AD1290 was 535.4×106 mu (Chinese area unit, 1 mu=666.7 m2), 57.8% in the north and 42.2% in the south. The fractional cropland areas for the entire study area, north, and south were 6.8%, 6.6%, and 7.1%, respectively and the per capita cropland areas for the whole study area, north, and south were 6.7, 15.6, and 4.1 mu, respectively. (4) Cropland was mainly distributed in the middle and lower reaches of the Yellow River (including the Fuli area), Huaihe River Basin (including Henan Province), and middle and lower reaches of the Yangtze River (including Jiangzhe, Jiangxi, and Huguang provinces).  相似文献   
288.
选取1990—2019年我国西部地区258次破坏性地震事件的灾害损失资料进行空间化处理,以每次地震烈度区的面积、死亡人数、受伤人数、直接经济损失等 4 个灾害损失量为指标,运用熵权法确定各指标的权重系数,划分我国西部地区各市(州)的5个历史地震灾害等级。结果表明,历史地震灾害极重的区域是四川省阿坝藏族羌族自治州、青海省玉树藏族自治州、云南省昭通市、新疆维吾尔自治区和田地区、云南省丽江市、新疆维吾尔自治区喀什地区、新疆维吾尔自治区巴音郭楞蒙古自治州、四川省雅安市、云南省楚雄彝族自治州;历史地震灾害严重的区域是青海省海南藏族自治州、新疆维吾尔自治区克孜勒苏柯尔克孜自治州、青海省甘孜藏族自治州、甘肃省定西市、内蒙古自治区巴彦淖尔市。  相似文献   
289.
Abstract

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During the past 400?years, Taiwan has experienced the dominance of various political regimes, which allowed the development of a diversity of cartographic styles for academic comparison. A detailed analysis of historical maps across centuries demonstrates that this contested island has been illustrated with a blending of reality, misconception and imagination. This paper narrates how maps reveal political rulers’ conscious and unconscious perceptions of this island. We call attention to the abundant cartographic materials in existence and suggest that they can be fascinating materials for the study of the contested colonial histories of this island in various disciplines.  相似文献   
290.
《The Cartographic journal》2013,50(3):270-277
Abstract

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The peninsula of Mount Athos is the largest monastic gathering of Modern Orthodoxy in the world, operating continually under the same regime since 883 AD. Focusing on Mount Athos, this paper attempts to examine the spatial regime continuation and identify the relation to what is considered to be a small residential unit around a central church (Protatos) within the limits of the Athos peninsula. The paper investigates the delimitation of the area, mapping and recording the relevant changes cartographically. At the same time, the paper creates a cadastral plan of the present regime, recording real estate owners in a cadastral table. Finally, the paper focuses on the significance of the findings to the historical geography of Athos, as well as the emergence of a new ‘area’, added to the twenty monasteries of the peninsula after 1450.  相似文献   
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