Climate change and impacts in the urban systems

A thesis submitted in partial fulfillment of the requirements for the degree of Doctor in Information Management, specialization in Geographic Information SystemsUrban systems are not only major drivers of climate change, but also impact hotspots. The processes of global warming and urban population growth make our urban agglomerations vulnerable to chain reactions triggered by climate related hazards. Hence, the reliable and cost-effective assessment of future climate impact is of high importance. Two major approaches emerge from the literature: i) detailed spatially explicit assessments, and ii) more holistic approaches consistently assessing multiple cities. In this multidisciplinary thesis both approaches were addressed. Firstly, we discuss the underlying reasons and main challenges of the applicability of downscaling procedures of climate projections in the process of urban planning. While the climate community has invested significant effort to provide downscaling techniques yielding localised information on future climate extreme events, these methods are not widely exploited in the process of urban planning. The first part of this research attempts to help bridge the gap between the communities of urban planners and climatologists. First, we summarize the rationale for such cooperation, supporting the argument that the spatial scale represents an important linkage between urban and climate science in the process of designing an urban space. Secondly, we introduce the main families of downscaling techniques and their application on climate projections, also providing the references to profound studies in the field. Thirdly, special attention is given to previous works focused on the utilization of downscaled ensembles of climate simulations in urban agglomerations. Finally, we identify three major challenges of the wider utilization of climate projections and downscaling techniques, namely: (i) the scale mismatch between data needs and data availability, (ii) the terminology, and (iii) the IT bottleneck. The practical implications of these issues are discussed in the context of urban studies. The second part of this work is devoted to the assessment of impacts of extreme temperatures across the European capital cities. In warming Europe, we are witnessing a growth in urban population with aging trend, which will make the society more vulnerable to extreme heat waves. In the period 1950-2015 the occurrence of extreme heat waves increased across European capitals. As an example, Moscow was hit by the strongest heat wave of the present era, killing more than ten thousand people. Here we focus on larger metropolitan areas of European capitals. By using an ensemble of eight EURO-CORDEX models under the RCP8.5 scenario, we calculate a suite of temperature based climate indices. We introduce a ranking procedure based on ensemble predictions using the mean of metropolitan grid cells for each capital, and socio-economic variables as a proxy to quantify the future impact. Results show that all the investigated European metropolitan areas will be more vulnerable to extreme heat in the coming decades. Based on the impact ranking, the results reveal that in near, but mainly in distant future, the extreme heat events in European capitals will be not exclusive to traditionally exposed areas such as the Mediterranean and the Iberian Peninsula. Cold waves will represent some threat in mid of the century, but they are projected to completely vanish by the end of this century. The ranking of European capitals based on their vulnerability to the extreme heat could be of paramount importance to the decision makers in order to mitigate the heat related mortality. Such a simplistic but descriptive multi-risk urban indicator has two major uses. Firstly, it communicates the risk associated with climate change locally and in a simple way. By allowing to illustratively relate to situations of other capitals, it may help to engage not only scientists, but also the decision makers and general public, in efforts to combat climate change. Secondly, such an indicator can serve as a basis to decision making on European level, assisting with prioritizing the investments and other efforts in the adaptation strategy. Finally, this study transparently communicates the magnitude of future heat, and as such contributes to raise awareness about heat waves, since they are still often not perceived as a serious risk. Another contribution of this work to communication of consequences of changing climate is represented by the MetroHeat web tool, which provides an open data climate service for visualising and interacting with extreme temperature indices and heat wave indicators for European capitals. The target audience comprises climate impact researchers, intermediate organisations, societal-end users, and the general public

OnGIS: Semantic Query Broker for Heterogeneous Geospatial Data Sources

Querying geospatial data from multiple heterogeneous sources backed by different management technologies poses an interesting problem in the data integration and in the subsequent result interpretation. This paper proposes broker techniques for answering a user's complex spatial query: finding relevant data sources (from a catalogue of data sources) capable of answering the query, eventually splitting the query and finding relevant data sources for the query parts, when no single source suffices. For the purpose, we describe each source with a set of prototypical queries that are algorithmically arranged into a lattice, which makes searching efficient. The proposed algorithms leverage GeoSPARQL query containment enhanced with OWL 2 QL semantics. A prototype is implemented in a system called OnGIS

The World Atlas of Desertification assessment concept for conscious land use solutions

The assessment concept that has been outlined for the compilation of the new World Atlas of Desertification (WAD) confronts this complexity by converging evidence of stress on the land system caused by various issues. Preventing judgement on the complex status of ‘land degradation’ the WAD opens the way to a positive approach to deal with the problem, providing also helpful evidence for stakeholders to design more conscious solutions for land use.JRC.H.5-Land Resources Managemen

Optical characterisation of three reference Dobsons in the ATMOZ Project – verification of G. M. B. Dobson's original specifications

Laboratory investigations of optical characteristics of three standard Dobsons provide real wavelength settings and slit functions. These parameters were compared with the original values given in the manuals. The differences between real and nominal values are not too large, but their application will in any case improve the quality of the total ozone column measurements in the global network. This improvement was the main objective of the ATMOZ project funding these activities.This work has been supported by the European Metrology Research Programme (EMRP) within the joint research project EMRP ENV59 ATMOZ “Traceability for atmospheric total column ozone”. The EMRP is jointly funded by the EMRP participating countries within EURAMET and the European Union

An insight into the present capabilities of national metrology institutes for measuring sparkle

Large effect pigments, due to their strongly specular reflectance, produce a special visual texture known as sparkle. The use of these pigments in many industries (automotive, cosmetic, paper, architecture...) makes the control of this visual texture necessary. A measurement scale has to be developed, so that traceability can be provided by national metrology institutes (NMI) or designated institutes. Some of them (PTB, METAS, CMI and CSIC) have tested their existing capabilities to measure sparkle, and their results are presented. Two possible sources of systematic errors have been identified: inadequate illumination and collection full-angles, and inadequate size of the virtual aperture used to assess the luminous flux reflected on the effect pigments. The measurement scale of sparkle used in this comparison is thoroughly presented. This comparison will allow the methodology to measure sparkle to be improved.This article was written within the EMPIR 16NRM08 Project “Bidirectional reflectance definition” (BiRD). The EMPIR is jointly funded by the EMPIR participating countries within EURAMET and the European Union. The EMPIR is jointly funded by the EMPIR participating countries within EURAMET and the European Union. Part of the authors (Instituto de Óptica “Daza de Valdés”) are also grateful to Comunidad de Madrid for funding the project S2018/NMT-4326-SINFOTON2-C

World Atlas of Desertification - Introductory Brochure

The brochure introduces the concept of the World Atlas of Desertification which relies on converging evidence of combined human-environment processes pointing out that land degradation cannot be modeled satisfactorily at global scales.The introductory brochure provides a short overview of the main land degradation issues, through illustration of a number key global datasets and some case study examples that reflect the global patterns and pathways to solutions. The brochure start with highlighting the human dominance that drives global environmental changes. The consequences of feeding a growing population include agriculture expansion and intensification, illustrated by maps and data on irrigation and nutrient use. Aridity and drought are important phenomena aggravating the already present human pressures on the environment. Other pressure patterns playing at global scale are illustrated with examples from China, India, S. America and the Sahel, along with a forward view on solutions.JRC.H.5-Land Resources Managemen

Characterization of Dobsons instruments within EMRP ATMOZ Project

Presentación realizada en: ATMOZ workshop at 11th RBCC-E, celebrado en El Arenosillo, Huelva, el 1 de junio de 2017

Preliminary measurement scales for sparkle and graininess

Large effect pigments, widely used in various fields of industrial applications, produce characteristic visual textures known as sparkle and graininess, which need to be quantified by objective or subjective methods. The development of preliminary measurement scales for sparkle and graininess, whose recommendation is now under discussion in the International Commission on Illumination (CIE), is described in this article. These scales are absolute, linear and traceable to standards of optical radiation metrology. The main purpose of this article is to justify the convenience of adopting these preliminary measurements scales, showing clear evidence that they correlate well with subjective evaluations. Before standardization, these scales need to be validated with more experimental data, including different specimens and experimental systems from other research groups.This article was written within the EMPIR 16NRM08 Project “Bidirectional reflectance definitions” (BiRD). The EMPIR is jointly funded by the EMPIR participating countries within EURAMET and the European Union. Part of the authors (E. Perales and F.M. Martínez-Verdú) are also grateful to Ministerio de Ciencia, Innovación y Universidades for project RTI2018-096000-B-I00

Predictable quantum efficient detector based on n-type silicon photodiodes

The predictable quantum efficient detector (PQED) consists of two custom-made induced junction photodiodes that are mounted in a wedged trap configuration for the reduction of reflectance losses. Until now, all manufactured PQED photodiodes have been based on a structure where a SiO2 layer is thermally grown on top of p-type silicon substrate. In this paper, we present the design, manufacturing, modelling and characterization of a new type of PQED, where the photodiodes have an Al2O3 layer on top of n-type silicon substrate. Atomic layer deposition is used to deposit the layer to the desired thickness. Two sets of photodiodes with varying oxide thicknesses and substrate doping concentrations were fabricated. In order to predict recombination losses of charge carriers, a 3D model of the photodiode was built into Cogenda Genius semiconductor simulation software. It is important to note that a novel experimental method was developed to obtain values for the 3D model parameters. This makes the prediction of the PQED responsivity a completely autonomous process. Detectors were characterized for temperature dependence of dark current, spatial uniformity of responsivity, reflectance, linearity and absolute responsivity at the wavelengths of 488 nm and 532 nm. For both sets of photodiodes, the modelled and measured responsivities were generally in agreement within the measurement and modelling uncertainties of around 100 parts per million (ppm). There is, however, an indication that the modelled internal quantum deficiency may be underestimated by a similar amount. Moreover, the responsivities of the detectors were spatially uniform within 30 ppm peak-to-peak variation. The results obtained in this research indicate that the n-type induced junction photodiode is a very promising alternative to the existing p-type detectors, and thus give additional credibility to the concept of modelled quantum detector serving as a primary standard. Furthermore, the manufacturing of PQEDs is no longer dependent on the availability of a certain type of very lightly doped p-type silicon wafers.Peer reviewe

Republic

Abstract. Ontologies, often defined as an explicit specification of conceptualization, are necessary for knowledge representation and knowledge exchange. Usually this means that ontology describes concepts and relations that exist in a domain. To enable knowledge exchange, it is necessary to describe these concepts and relations in a better way than just ordering them in taxonomy. However, ontology design usually starts and stops with designing taxonomies. We present a method that is based on formal concept analysis, which is a theory of data analysis which identifies conceptual structures among data sets. This method allows for discovering necessity for new concepts and relations in an ontology, which leads to an ontology that has these entities described in a way suitable for knowledge exchange.