Gone With the Wind: How California Is Losing Its Clean Power Edge to Texas

Tracks the slow demise of wind, solar, geothermal, and biomass industries in the very state that pioneered the technologies

Efficient, image-based appearance acquisition of real-world objects

Two ingredients are necessary to synthesize realistic images: an accurate rendering algorithm and, equally important, high-quality models in terms of geometry and reflection properties. In this dissertation we focus on capturing the appearance of real world objects. The acquired model must represent both the geometry and the reflection properties of the object in order to create new views of the object with novel illumination. Starting from scanned 3D geometry, we measure the reflection properties (BRDF) of the object from images taken under known viewing and lighting conditions. The BRDF measurement require only a small number of input images and is made even more efficient by a view planning algorithm. In particular, we propose algorithms for efficient image-to-geometry registration, and an image-based measurement technique to reconstruct spatially varying materials from a sparse set of images using a point light source. Moreover, we present a view planning algorithm that calculates camera and light source positions for optimal quality and efficiency of the measurement process. Relightable models of real-world objects are requested in various fields such as movie production, e-commerce, digital libraries, and virtual heritage.Zur Synthetisierung realistischer Bilder ist zweierlei nötig: ein akkurates Verfahren zur Beleuchtungsberechnung und, ebenso wichtig, qualitativ hochwertige Modelle, die Geometrie und Reflexionseigenschaften der Szene repräsentieren. Die Aufnahme des Erscheinungbildes realer Gegenstände steht im Mittelpunkt dieser Dissertation. Um beliebige Ansichten eines Gegenstandes unter neuer Beleuchtung zu berechnen, müssen die aufgenommenen Modelle sowohl die Geometrie als auch die Reflexionseigenschaften beinhalten. Ausgehend von einem eingescannten 3D-Geometriemodell, werden die Reflexionseigenschaften (BRDF) anhand von Bildern des Objekts gemessen, die unter kontrollierten Lichtverhältnissen aus verschiedenen Perspektiven aufgenommen wurden. Für die Messungen der BRDF sind nur wenige Eingabebilder erforderlich. Im Speziellen werden Methoden vorgestellt für die Registrierung von Bildern und Geometrie sowie für die bildbasierte Messung von variierenden Materialien. Zur zusätzlichen Steigerung der Effizienz der Aufnahme wie der Qualität des Modells, wurde ein Planungsalgorithmus entwickelt, der optimale Kamera- und Lichtquellenpositionen berechnet. Anwendung finden virtuelle 3D-Modelle bespielsweise in der Filmproduktion, im E-Commerce, in digitalen Bibliotheken wie auch bei der Bewahrung von kulturhistorischem Erbe

High-resolution land use and land cover dataset for regional climate modelling: Historical and future changes in Europe

Anthropogenic land-use and land cover change (LULCC) is a major driver of environmental changes. The biophysical impacts of these changes on the regional climate in Europe are currently extensively investigated within the WCRP CORDEX Flagship Pilot Study (FPS) LUCAS - "Land Use and Climate Across Scales" using an ensemble of different Regional Climate Models (RCMs) coupled with diverse Land Surface Models (LSMs). In order to investigate the impact of realistic LULCC on past and future climates, high-resolution datasets with observed LULCC and projected future LULCC scenarios are required as input for the RCM-LSM simulations. To account for these needs, we generated the LUCAS LUC dataset Version 1.1 at 0.1&deg; resolution for Europe with annual LULC maps from 1950&ndash;2100 (Hoffmann et al., 2022b, a), which is tailored towards the use in state-of-the-art RCMs. The plant functional type distribution (PFT) for the year 2015 (i.e., LANDMATE PFT dataset) is derived from the European Space Agency Climate Change Initiative Land Cover (ESA-CCI LC) dataset. Details about the conversion method, cross-walking procedure and the evaluation of the LANDMATE PFT dataset are given in the companion paper by &nbsp;Reinhart et al. (2022b). Subsequently, we applied the land-use change information from the Land-Use Harmonization 2 (LUH2) dataset, provided at 0.25&deg; resolution as input for CMIP6 experiments, to derive LULC distribution at high spatial resolution and at annual timesteps from 1950 to 2100. In order to convert land use and land management change information from LUH2 into changes in the PFT distribution, we developed a Land Use Translator (LUT) specific to the needs of RCMs. The annual PFT maps for Europe for the period 1950 to 2015 are derived from the historical LUH2 dataset by applying the LUT backward from 2015 to 1950. Historical changes in the forest type changes are considered using an additional European forest species dataset. The historical changes in the PFT distribution of LUCAS LUC follow closely the land use changes given by LUH2 but differ in some regions compared to other annual LULCC datasets. From 2016 onward, annual PFT maps for future land use change scenarios based on LUH2 are derived for different Shared Socioeconomic Pathways (SSPs) and Representative Concentration Pathways (RCPs) combinations used in the framework of the Coupled Modelling Intercomparison Project Phase 6 (CMIP6). The resulting LULCC maps can be applied as land use forcing to the new generation of RCM simulations for downscaling of CMIP6 results. The newly developed LUT is transferable to other CORDEX regions world-wide.</p