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Abstract:Both calibration and uncertainty assessment are mandatory steps in today's modelling process. The former considers both the inputs (input variables and parameters) as well as model results. An exploratory investigation of the applicable parameter space results in a wide spectrum of values for a specific model output. By retaining only those model realizations that mimic reality in a sufficient way, inputs and associated response can be constrained, thereby quantifying the uncertainty involved. The generalized likelihood uncertainty estimation (GLUE) framework provides a structured methodology for this purpose.The study presented focuses on the applicability of the GLUE framework within the context of the distributed hydrological model MIKE SHE. Even though all significant processes involved are incorporated within the model, the problems of calibration and uncertainty assessment cannot be avoided. This has resulted in a quest for welldelineated effective parameters crucial for sound mechanistic model application. Being a complex model, the number of possible realizations using MIKE SHE is fairly small due to computing time, and an in-depth exploratory approach is impossible. On the other hand, several output variables are available aside from the hydrological river response, like water content in the soil profile or ground water level, which can be used for retaining realistic parameter sets.This study presents some preliminary results on the applicability of the GLUE-MIKE SHE framework and associated constrained preliminary parameter and output uncertainty values. Focus was given to the influence of soil hydraulic parameters on the hydrological behaviour of a small study basin. The soil hydraulic parameters were predicted using various pedo-transfer-function approaches and moisture retention measurements in the laboratory, and these distributions were then confronted with ranges of the constrained effective parameters. For the latter, the restrictions that were imposed based on behavioural acceptance were substantial. All the traditional methods show significant uncertainty, due to heterogeneity and model error, which cannot be disregarded. The first results suggest a reasonable match among effective parameters and laboratory measurements. The use of pedo-transfer-function distributions as effective parameters, however, may provide unacceptable results, even with liberal criteria.

[1] A methodology to qualify and quantify uncertainty and sensitivity measures, mathematically related to a representative metamodel and correlation coefficients, using the Latin hypercube approach, is evaluated in the context of the spatially distributed hydrological model MIKE SHE. The characteristics of various outputs, such as cumulative catchment discharge, average soil water content, and groundwater elevation, are examined at different time and space scales. The soil hydraulic parameters make up the varying input. The input uncertainties and the corresponding Latin hypercube parameter perturbations are based on U.S. Department of Agriculture texture figures. Results indicate important differences between the measures, even in ranking, making combined interpretation of the measures necessary. The real-world problem of correlation among parameters adds significant complexity to the assessment of uncertainty and sensitivity and cannot be disregarded without caution. The presented methodology, though still CPU intensive, allows the hydrological modeler to cope with this complexity.

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The overthrow of the democratically elected socialist president Salvador Allende in Chile and the human rights violations under the military junta of Augusto Pinochet spawned one of the most iconic and sustained human rights campaigns of the Cold War. Human rights scholars have argued that this movement on behalf of Chile signalled the “breakthrough” of human rights as the lingua franca of transnational activism. They have emphasized the global dimensions of these campaigns, which inspired movements mobilizing on behalf of other issues in the Third World. However, such narratives have not been corroborated by research on the campaigns as developed in Europe. Historians have so far focused on the impact of the Chilean crisis in specific countries or on particular organizations, and on the ways in which human rights activism was coloured by local and national contexts. This article aims to shift the scope of the debate by establishing relations with and crossovers from other transnational causes and campaigns, analysing the ways in which campaigns on behalf of Chile became intimately related to campaigns on intra-European issues during the 1970s and 1980s. It explores the so far little-studied connections between campaigns over Chile and simultaneously burgeoning movements on behalf of East–West détente, resistance against authoritarian regimes in Southern Europe, and the plight of dissidents in Eastern Europe. It argues that campaigns on behalf of Chile were reconfigured around European themes, created bonds of solidarity within a divided Europe, and drew on analogies rather than a juxtaposition between Europe and the Third World.