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ON 16 NOVEMBER 2000, the final report of the World Commission on Dams (WCD) was launched in London, in the presence of South Africa’s former president Nelson Mandela. This represented a remarkable milestone in the history of dam policy and politics. During its two-year existence, WCD had conducted the most extensive review of research and evidence regarding the planning, impacts, and management of large dams. It had engaged with numerous stakeholders around the globe. It also made comprehensive recommendations about how to improve dam planning and management.

Responses to recent climatic changes in the sediment of subarctic Lake Saanajärvi in northwestern Finnish Lapland are studied by comparison of various biological and sedimentological proxies with the 200-year long climate record, specifically reconstructed for the site using a data-set of European-wide meteorological data. The multi-proxy evidence of simultaneously changing diatom, Cladocera, and chrysophyte assemblages along with the increased rates of organic matter accumulation and pigment concentrations suggest that the lake has undergone a distinct typological change starting from the turn of the 20th century. This change, indicating an increase in lake productivity, parallels a pronounced rise in the meteorologically reconstructed mean annual and summer temperatures in the region between ca. 1850 and 1930's. We postulate that, during the Little Ice Age, the lake was not, or was only weakly, thermally stratified during summer, whereas the subsequent increase in air and hence epilimnetic water temperatures resulted in the development of the present summer stratification. The increased thermal stability of the lake created more suitable conditions for the growth of phyto- and zooplankton and changed the overall primary production from benthos to plankton. Mineral magnetic and carbonaceous particle records suggest long-distance pollution, particularly since the 1920's, yet the observed changes in lake biota and productivity can hardly be explained by this very minor background pollution; the 20th century species configurations are typical of neutral waters and do not indicate any response to pollution.

Industrial poplar plantations represent a strategic source of wood products for many countries. Harvested after 10 to 30 years, they yield about 200 t ha-1 of timber and 100 t ha-1 industrial wood. The latter is obtained from poplar tops, which can be converted into chips, or a mix of pulpwood and chips. The study compared four options to process poplar tops. Alternatives derived from the intersection of two product strategies (pulpwood and chips, or chips only) with two pulpwood processing methods (manual or mechanized). Both mechanization and simplification (only one product) succeeded in reducing production cost, but the former had a stronger effect. The tests demonstrated that all options were cost-effective and could return some profits. However, the exclusive production of chips offered lower profits, compared to an articulate product strategy aimed at maximising value recovery. In the case of Italian poplar plantations, the price difference between pulp and chips is generally larger than the cost reduction obtained with integral chipping. Similar conclusions were reached by other authors working with spruce and beech in Central Europe. Of course, this is only true for the current price levels of pulpwood and chips: results may change, if this price balance will be altered by the growing demand for biomass fuel.

Scientific evidence and evidence-based reasoning are likely to face epistemological challenges when brought into societal debate if their foundational assumptions generate cognitive dissonance among key elements of the community. The risk of dissonance is even greater when scientific demonstrations and models are concerned with the decisions and behaviours of people interacting with an environment of interest. In this case, scientific information is often perceived as distorted or biased due to the inherent uncertainties attached to human ecosystems Human ecosystems are complex and adaptive, largely due to our individual cognitive capacities and communication skills. Complex systems science aims to track uncertainties attached to these systems by exploring metaphoric models of reality.

Slides presented at the 102 Annual American Meteorological Society Meeting, as part of the session "Major Weather Events and Impacts of 2021" (paper 6.3 - It's Getting Hot in Here: Real-Time Climate Fingerprints Applied to the 2021 Extreme Heat Season) For more information, please reach out to Daniel Gilford at dgilford@climatecentral.org. Presentation Abstract: Extreme heat was observed and experienced across large portions of the United States in 2021, including during notable record-breaking events in the Pacific Northwest, the Southwest, and along the East coast. The contiguous US experienced its hottest June on record, and excess heat related deaths stretched into the thousands. While more frequent and intense periods of extreme heat are expected consequences of anthropogenic climate change, rapidly and continuously assessing the degree to which human emissions of greenhouse gases increase the likelihood of a specific event remains a challenging technical process. In this study we introduce the Realtime Climate attribution framework and illustrate its application through an analysis of observed 2021 extreme heat events. The framework implements one model-based and two observation-based approaches to produce three distinct attribution assessments, including best estimates and uncertainties. The framework is designed to be flexible across a range of variables and scales, computationally lightweight, and adaptable for impact studies. Using a suite of global climate models, observed global mean temperatures, and local observed daily temperatures, we quantify the extent to which human-driven climate change made 2021 maximum and minimum daily temperature extremes more likely across the United States. Results confirm the continued and growing influence of human-driven climate change in local weather extremes. For instance, we find that the record-breaking high temperatures in June near Phoenix, AZ, were at least 3.25 times more likely because of human activity. Through this framework, we are building the capacity to produce attribution estimates while an event is unfolding. Furthermore, the ability to estimate attribution levels continuously will enhance studies of extreme heat impacts on human health, along with other socioeconomic or influences.

| openaire: EC/FP7/307315/EU//SOLARX Light-and elevated temperature-induced degradation (LeTID) is a detrimental effect observed under operating conditions in p-Type multicrystalline silicon (mc-Si) solar cells. In this contribution, we employ synchrotron-based techniques to study the dissolution of precipitates due to different firing processes at grain boundaries in LeTID-Affected mc-Si. The synchrotron measurements show clear dissolution of collocated metal precipitates during firing. We compare our observations with degradation behavior in the same wafers. The experimental results are complemented with process simulations to provide insight into the change in bulk point defect concentration due to firing. Several studies have proposed that LeTID is caused by metal-rich precipitate dissolution during contact firing, and we find that the solubility and diffusivity are promising screening metrics to identify metals that are compatible with this hypothesis. While slower and less soluble elements (e.g., Fe and Cr) are not compatible according to our simulations, the point defect concentrations of faster and more soluble elements (e.g., Cu and Ni) increase after a high-Temperature firing process, primarily due to emitter segregation rather than precipitate dissolution. These results are a useful complement to lifetime spectroscopy techniques, and can be used to evaluate additional candidates in the search for the root cause of LeTID. Peer reviewed

There is a growing body of literature in the field of urban climate change adaptation planning that indicate a need to address climate change planning measures from a more holistic sustainable development perspective. This paper presents the findings from a recently completed study that indicates there remain significant unresolved tensions between the development pathways and the climate change adaptation strategies of the 58 cities within the C40 Cities Climate Leadership Group.

Since a superconductor has no resistance below a certain temperature and can therefore save a large amount of energy dissipated, it is a 'green' material by saving energy loss and hence reducing carbon emissions. Recently the massive manufacture of high-temperature superconducting (HTS) materials has enabled superconductivity to become a preferred candidate to help generation and transportation of cleaner energy. One of the most promising applications of superconductors is Superconducting Magnetic Energy Storage (SMES) systems, which are becoming the enabling engine for improving the capacity, efficiency, and reliability of the electric system. SMES systems store energy in the magnetic field created by the flow of direct current in a superconducting coil. SMES systems have many advantages compared to other energy storage systems: high cyclic efficiency, fast response time, deep discharge and recharge ability, and a good balance between power density and energy density. Based on these advantages, SMES systems will play an indispensable role in improving power qualities, integrating renewable energy sources and energizing transportation systems. This thesis describes an intensive study of superconducting pancake coils wound using second-generation(2G) HTS materials and their application in SMES systems. The specific contribution of this thesis includes an innovative design of the SMES system, an easily calculated, but theoretically advanced numerical model to analyse the system, extensive experiments to validate the design and model, and a complete demonstration experiment of the prototype SMES system. This thesis begins with literature review which includes the introduction of the background theory of superconductivity and development of SMES systems. Following the literature review is the theoretical work. A prototype SMES system design, which provides the maximum stored energy for a particular length of conductors, has been investigated. Furthermore, a new numerical model, which can predict all necessary operation parameters, including the critical current and AC losses of the system, is presented. This model has been extended to analyse superconducting coils in different situations as well. To validate the theoretical design and model, several superconducting coils, which are essential parts of the prototype SMES system, together with an experimental measurement set-up have been built. The coils have been energized to test their energy storage capability. The operation parameters including the critical current and AC losses have been measured. The results are consistent with the theoretical predictions. Finally the control system is developed and studied. A power electronics control circuit of the prototype SMES system has been designed and simulated. This control circuit can energize or discharge the SMES system dynamically and robustly. During a voltage sag compensation experiment, this SMES prototype monitored the power system and successfully compensated the voltage sag when required. By investigating the process of building a complete system from the initial design to the final experiment, the concept of a prototype SMES system using newly available 2G HTS tapes was validated. This prototype SMES system is the first step towards the implementation of future indsutrial SMES systems with bigger capacities, and the knowledge obtained through this research provides a comprehensive overview of the design of complete SMES systems. The full text of this thesis is not available due to ongoing discussions regarding publication

The database presents the scenario results of an exploratory research, carried out at the International Institute for Applied Systems Analysis (IIASA): the Low Energy Demand (LED) study (Grubler et al. 2018). The LED scenario explored how far transformative changes that combine technological changes, end-use efficiency, and new business models for energy service provision can lead for lowering energy demand, and how these changes could drive deep decarbonisation in the long-term. The scenario development methodology included a bottom-up analysis of how currently existing, though often embryonic, social, institutional, and technological trends could become mainstream with resulting step-changes in efficiency and resulting lowered energy demand. The bottom-up demand estimations were then further explored for their supply side and emissions and climate implications with a top-down modeling framework drawing on the Shared Socioeconomic Pathways (SSP) framework (Riahi et al. 2017). The results show that global final energy demands can be drastically reduced in 2050, to around 245 EJ/yr, or 40% lower than today, whilst significantly expanding human welfare and reducing global development inequalities. According to the knowledge of the authors, LED is the lowest long-term global energy demand scenario ever published. The LED scenario meets the 1.5°C climate target in 2100 without overshoot and keeps the global mean temperature increase below 1.5°C with a probability of more than 60%, without requiring controversial negative emission technologies, such as bioenergy with carbon capture and storage (BECCS), that figure prominently in the emission scenario literature (Rogelj et al. 2015, Anderson and Peters 2016, Creutzig et al. 2016, Smith et al. 2016). Furthermore, the beneficial impacts of the LED scenario on a range of other sustainable development goals are also shown, demonstrating that efficiency of energy services provision plays a critical role in reaching low-energy futures without compromising increased living standards in the Global South, while at the same time reducing adverse social and environmental impacts of climate mitigation strategies that focus predominantly on large-scale supply-side transformations. The research is published in a peer-reviewed article in Nature Energy (Grubler et al. 2018) with ample supplementary information. Water consumption and withdrawal data are published in Parkinson et al. (2018). The data is available for download from the LED Database. The content of the LED database and any derived analysis may only be used for non-commercial scientific publications, articles, educational purposes, figures and data tables provided that the source reference pursuant to section 'Required citation' is included and all relevant publications are correctly cited. Partial reproductions of the database content may be stored in online repositories, if this is necessary to comply with a journal's data archiving and access requirements. Such reproductions must be limited to the scope of the manuscript in question, and must include a hyperlink to the source database hosted at https://db1.ene.iiasa.ac.at/LEDDB and the download date from the source database. However, any wholesale duplication, translation, reworking, processing, arrangement, transformation, or reproduction through the internet or any other channels, of the https://db1.ene.iiasa.ac.at/LEDDEB for commercial or non-commercial purposes is not permitted without the explicit written approval of IIASA.