From impacts to embodied experiences: tracing political ecology in climate change research

Political ecology has long moved on from its initial skepticism of big science engagements and cursory critiques of simplistic vulnerability approaches. Its core strengths lie in understanding the contestation of inequalities, marginalization, and injustices in access to and control over resources, neoliberal politics of environmental change, and dominant environmental narratives, while incorporating new insights from development ethics, feminist social theory, and resilience thinking. Today’s theoretical lenses allow for an understanding of causal relations in climate debates that exceed narrowly defined impact studies. I focus on four areas that exemplify shifts in engagement with adaptation, stretch themes of inquiry, and delineate zones for analysis and action: (1) reconnecting scale: multiscalar interactions, scalar dimensions of practice, and traversing scales from embodied experiences to the global intimate; (2) destabilizing gender: from gendered vulnerability and adaptive capacity to fragmented identities and intersectionality; (3) repositioning persistent inequalities: from rights to responsibilities, mutual fragility, and human security; and (4) reframing certainty: from climate proofing to limits, traps, and transformative change. Methodologically, I advocate for opening space for collective and anticipatory learning, creative envisioning, rehearsing for reality, and dynamic planning in the context of multiple and synergistic stressors, all powerful countervoices to hegemonic integrated modeling and numeric vulnerability indices.     

非稳态地震记录时变子波估计

地震子波估计是地震资料处理和解释中的一个关键问题,子波估计的可靠性会直接影响反褶积和反演的准确度.现有的子波估计方法分为确定型和统计型两种类型,本文通过结合这两类方法,利用确定型的谱分析法和统计型的偏度最大化方法,分别提取时变子波的振幅和相位信息,得到估计的时变子波.这种方法不需要对子波进行任何时不变或相位等的假设,具有对时变相位的估计能力.进而利用估计时变子波进行非稳态反褶积,提高地震记录的保真度,为精细储层预测和描述提供高质量的剖面.理论模型试算验证了方法的可行性,通过实际地震资料的处理应用,表明该方法能有效地提取出子波时变信息.

     

Error distribution modelling of satellite soil moisture measurements for hydrological applications

Satellite‐based soil moisture data accuracies are of important concerns by hydrologists because they could significantly influence hydrological modelling uncertainty. Without proper quantification of their uncertainties, it is difficult to optimize the hydrological modelling system and make robust decisions. Currently, the satellite soil moisture data uncertainty has been limited to summary statistics with the validations mainly from the in situ measurements. This study attempts to build the first error distribution model with additional higher‐order uncertainty modelling for satellite soil moisture observations. The methodology is demonstrated by a case study using the Soil Moisture and Ocean Salinity satellite soil moisture observations. The validation is based on soil moisture estimates from hydrological modelling, which is more relevant to the intended data use than the in situ measurements. Four probability distributions have been explored to find suitable error distribution curves using the statistical tests and bootstrapping resampling technique. General extreme value is identified as the most suitable one among all the curves. The error distribution model is still in its infant stage, which ignores spatial and temporal correlations, and nonstationarity. Further improvements should be carried out by the hydrological community by expanding the methodology to a wide range of satellite soil moisture data using different hydrological models. Copyright © 2016 John Wiley & Sons, Ltd.     

Uncertainty assessment in river flow projections for Ethiopia’s Upper Awash Basin using multiple GCMs and hydrological models

ABSTRACT

Uncertainty in climate change impacts on river discharge in the Upper Awash Basin, Ethiopia, is assessed using five MIKE SHE hydrological models, six CMIP5 general circulation models (GCMs) and two representative concentration pathways (RCP) scenarios for the period 2071–2100. Hydrological models vary in their spatial distribution and process representations of unsaturated and saturated zones. Very good performance is achieved for 1975–1999 (NSE: 0.65–0.8; r: 0.79–0.93). GCM-related uncertainty dominates variability in projections of high and mean discharges (mean: –34% to +55% for RCP4.5, – 2% to +195% for RCP8.5). Although GCMs dominate uncertainty in projected low flows, inter-hydrological model uncertainty is considerable (RCP4.5: –60% to +228%, RCP8.5: –86% to +337%). Analysis of variance uncertainty attribution reveals that GCM-related uncertainty occupies, on average, 68% of total uncertainty for median and high flows and hydrological models no more than 1%. For low flows, hydrological model uncertainty occupies, on average, 18% of total uncertainty; GCM-related uncertainty remains substantial (average: 28%).     

A Methodology for Reliability-Based Design of Rock Slopes

Summary A reliability-based methodology for the design of rock slopes, that can easily be implemented by the practicing engineers is proposed. The advanced first-order second-moment (AFOSM) method is adopted as the reliability assessment model and its application is illustrated for the case of plane failure. A model is developed within the framework of first-order second-moment approach to analyze the uncertainties underlying the in situ shear strength properties of rock discontinuities. Here, particular emphasis is given on the assessment of uncertainties related to the shear characteristics of clean, unfilled rock discontinuities under low normal stress levels. An extensive literature survey on the shear characteristics of discontinuities is carried out in order to collect data for the quantification of uncertainties. The data extracted from this literature survey are classified and reprocessed so that they can be utilized in the uncertainty analysis model. A user friendly software called ROCKREL is developed to carry out the numerical computations and to make the proposed design format more practical. Received April 16, 2001; accepted June 10, 2002; Published online November 19, 2002 Authors' address: Prof. Celal Karpuz, Middle East Technical University, Faculty of Engineering, Department of Mining Engineering, 06531 Ankara, Turkey; e-mail: karpuz @metu.edu.tr     

基于水位流量关系的流量估算不确定性分析

针对现有水位流量关系线型物理机制不强及流量估算不确定性来源考虑不充分问题,以北江流域石角水文站为例,推导该测站水位流量关系,基于BaRatin模型评估流量测量误差及率定样本选取对估算流量不确定性的影响。发现河槽控制宽浅矩形断面水位流量关系为幂函数,其系数可用糙率、河宽、比降表达,指数为定值5/3;考虑流量测量误差后高水估算流量总不确定性减小32%;率定数据增加1倍、3倍,高水估算流量总不确定性减小12%、34%。结果表明:① 水位流量关系模型建立方法可推广至多类型测站;② 高水测量误差对率定精度影响较大,建议提高高水流量测量精度;③ 现有实测水位与流量数据存在信息冗余,主要存在于低水数据中,本方法可减少率定数据使用,降低整编成本。     

A MODEL FOR QUANTITATIVELY ESTIMATING SHORT-RANGE PRECIPITATION BASED ON GMS DIGITALIZED CLOUD MAPS—PART Ⅱ:ASSESSMENT OF RESULTS FROM THE MODEL FOR SATELLITE-IMAGE QUANTITATIVELY ESTIMATING PRECIPITATION

This is Part Ⅱ of this series.It introduces the technique for recognizing MαCS phased properties and its precipitation center or centers by means of dynamic digitalized cloud maps and presents the assessment of the effectiveness of the model proposed in Part Ⅰ as to its fitting and forecasting accuracy.     

氧化钕中杂质氧化镍含量的测定及测量结果的不确定度分析

采用电感耦合等离子体发射光谱法(ICP-OES)法测定氧化钕中杂质氧化镍的含量,得到氧化镍含量为0.002 7%,分析了检测过程中的各个影响因素,并对测量结果的可靠性以相对扩展不确定度表示(U_rel=12%,k=2)。相对不确定度分量计算结果表明,标准曲线拟合时引入的相对不确定度分量最大,u_rel(c₂)=5.639%,其次为标准溶液配制过程中引入的相对不确定度分量u_rel(c₁)=0.879%。本文可为相关检测人员的结果不确定度分析提供参考。     

边角后方交会的精度分析及布设方案选择

在推出边角后方会简捷精度估算式的基础上,分析并给出了待定点较优的选择区域,还讨论了其解的多值性问题及实质,针对边角后方交会应用中有较严格的布点限制,提出了双边单角后方交会的布设方案;文中给出了其点位与精度计算的固定公式,并附有实例难证。