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Project: Coupled Model Intercomparison Project Phase 6 (CMIP6) datasets - These data have been generated as part of the internationally-coordinated Coupled Model Intercomparison Project Phase 6 (CMIP6; see also GMD Special Issue: http://www.geosci-model-dev.net/special_issue590.html). The simulation data provides a basis for climate research designed to answer fundamental science questions and serves as resource for authors of the Sixth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC-AR6). CMIP6 is a project coordinated by the Working Group on Coupled Modelling (WGCM) as part of the World Climate Research Programme (WCRP). Phase 6 builds on previous phases executed under the leadership of the Program for Climate Model Diagnosis and Intercomparison (PCMDI) and relies on the Earth System Grid Federation (ESGF) and the Centre for Environmental Data Analysis (CEDA) along with numerous related activities for implementation. The original data is hosted and partially replicated on a federated collection of data nodes, and most of the data relied on by the IPCC is being archived for long-term preservation at the IPCC Data Distribution Centre (IPCC DDC) hosted by the German Climate Computing Center (DKRZ). The project includes simulations from about 120 global climate models and around 45 institutions and organizations worldwide. Summary: These data include the subset used by IPCC AR6 WGI authors of the datasets originally published in ESGF for 'CMIP6.AerChemMIP.HAMMOZ-Consortium.MPI-ESM-1-2-HAM' with the full Data Reference Syntax following the template 'mip_era.activity_id.institution_id.source_id.experiment_id.member_id.table_id.variable_id.grid_label.version'. The MPI-ESM1.2-HAM climate model, released in 2017, includes the following components: aerosol: HAM2.3, atmos: ECHAM6.3 (spectral T63; 192 x 96 longitude/latitude; 47 levels; top level 0.01 hPa), atmosChem: sulfur chemistry (unnamed), land: JSBACH 3.20, ocean: MPIOM1.63 (bipolar GR1.5, approximately 1.5deg; 256 x 220 longitude/latitude; 40 levels; top grid cell 0-12 m), ocnBgchem: HAMOCC6, seaIce: unnamed (thermodynamic (Semtner zero-layer) dynamic (Hibler 79) sea ice model). The model was run by the ETH Zurich, Switzerland; Max Planck Institut fur Meteorologie, Germany; Forschungszentrum Julich, Germany; University of Oxford, UK; Finnish Meteorological Institute, Finland; Leibniz Institute for Tropospheric Research, Germany; Center for Climate Systems Modeling (C2SM) at ETH Zurich, Switzerland (HAMMOZ-Consortium) in native nominal resolutions: aerosol: 250 km, atmos: 250 km, atmosChem: 250 km, land: 250 km, ocean: 250 km, ocnBgchem: 250 km, seaIce: 250 km.

Project: Coupled Model Intercomparison Project Phase 6 (CMIP6) datasets - These data have been generated as part of the internationally-coordinated Coupled Model Intercomparison Project Phase 6 (CMIP6; see also GMD Special Issue: http://www.geosci-model-dev.net/special_issue590.html). The simulation data provides a basis for climate research designed to answer fundamental science questions and serves as resource for authors of the Sixth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC-AR6). CMIP6 is a project coordinated by the Working Group on Coupled Modelling (WGCM) as part of the World Climate Research Programme (WCRP). Phase 6 builds on previous phases executed under the leadership of the Program for Climate Model Diagnosis and Intercomparison (PCMDI) and relies on the Earth System Grid Federation (ESGF) and the Centre for Environmental Data Analysis (CEDA) along with numerous related activities for implementation. The original data is hosted and partially replicated on a federated collection of data nodes, and most of the data relied on by the IPCC is being archived for long-term preservation at the IPCC Data Distribution Centre (IPCC DDC) hosted by the German Climate Computing Center (DKRZ). The project includes simulations from about 120 global climate models and around 45 institutions and organizations worldwide. Summary: These data include the subset used by IPCC AR6 WGI authors of the datasets originally published in ESGF for 'CMIP6.CMIP.HAMMOZ-Consortium.MPI-ESM-1-2-HAM.historical' with the full Data Reference Syntax following the template 'mip_era.activity_id.institution_id.source_id.experiment_id.member_id.table_id.variable_id.grid_label.version'. The MPI-ESM1.2-HAM climate model, released in 2017, includes the following components: aerosol: HAM2.3, atmos: ECHAM6.3 (spectral T63; 192 x 96 longitude/latitude; 47 levels; top level 0.01 hPa), atmosChem: sulfur chemistry (unnamed), land: JSBACH 3.20, ocean: MPIOM1.63 (bipolar GR1.5, approximately 1.5deg; 256 x 220 longitude/latitude; 40 levels; top grid cell 0-12 m), ocnBgchem: HAMOCC6, seaIce: unnamed (thermodynamic (Semtner zero-layer) dynamic (Hibler 79) sea ice model). The model was run by the ETH Zurich, Switzerland; Max Planck Institut fur Meteorologie, Germany; Forschungszentrum Julich, Germany; University of Oxford, UK; Finnish Meteorological Institute, Finland; Leibniz Institute for Tropospheric Research, Germany; Center for Climate Systems Modeling (C2SM) at ETH Zurich, Switzerland (HAMMOZ-Consortium) in native nominal resolutions: aerosol: 250 km, atmos: 250 km, atmosChem: 250 km, land: 250 km, ocean: 250 km, ocnBgchem: 250 km, seaIce: 250 km.

Supplementary material for the publication " Agricultural biogas plants as a hub to foster circular economy and bioenergy: An assessment using material substance and energy flow analysis" Burg, V., b, Rolli, C., Schnorf, V., Scharfy, D., Anspach, V., Bowman, G. Today's agro-food system is typically based on linear fluxes (e.g. mineral fertilizers importation), when a circular approach should be privileged. The production of biogas as a renewable energy source and digestate, used as an organic fertilizer, is essential for the circular economy in the agricultural sector. This study investigates the current utilization of wet biomass in agricultural anaerobic digestion plants in Switzerland in terms of mass, nutrients, and energy flows, to see how biomass use contributes to circular economy and climate change mitigation through the substitution effect of mineral fertilizers and fossil fuels. We quantify the system and its benefits in details and examine future developments of agricultural biogas plants using different scenarios. Our results demonstrate that agricultural anaerobic digestion could be largely increased, as it could provide ten times more biogas by 2050, while saving significant amounts of mineral fertilizer and GHG emissions.

Project: GCOS Earth Heat Inventory - A study under the Global Climate Observing System (GCOS) concerted international effort to update the Earth heat inventory (EHI), and presents an updated international assessment of ocean warming estimates, and new and updated estimates of heat gain in the atmosphere, cryosphere and land over the period from 1960 to present. Summary: The file “GCOS_EHI_1960-2020_Earth_Heat_Inventory_Ocean_Heat_Content_data.nc” contains a consistent long-term Earth system heat inventory over the period 1960-2020. Human-induced atmospheric composition changes cause a radiative imbalance at the top-of-atmosphere which is driving global warming. Understanding the heat gain of the Earth system from this accumulated heat – and particularly how much and where the heat is distributed in the Earth system - is fundamental to understanding how this affects warming oceans, atmosphere and land, rising temperatures and sea level, and loss of grounded and floating ice, which are fundamental concerns for society. This dataset is based on a study under the Global Climate Observing System (GCOS) concerted international effort to update the Earth heat inventory published in von Schuckmann et al. (2020), and presents an updated international assessment of ocean warming estimates, and new and updated estimates of heat gain in the atmosphere, cryosphere and land over the period 1960-2020. The dataset also contains estimates for global ocean heat content over 1960-2020 for different depth layers, i.e., 0-300m, 0-700m, 700-2000m, 0-2000m, 2000-bottom, which are described in von Schuckmann et al. (2022). This version includes an update of heat storage of global ocean heat content, where one additional product (Li et al., 2022) had been included to the initial estimate. The Earth heat inventory had been updated accordingly, considering also the update for continental heat content (Cuesta-Valero et al., 2023).

What is the future of the manifold landscapes and territories across the world which support contemporary cities, such as Zurich, with water, food, human labour and other resources? How is human and non-human life in these environments affected by cities and by urbanisation? In our discipline, discussions on sustainability have remained focused on buildings and on cities, while these extended territories are equally exposed to rapid and far-reaching transformations with massive social and environmental implications. How can architects respond to these urgent changes? Can architecture become ecological, to go beyond-the-human and beyond-the-built, in order to engage with the environment as a whole?

Hydro-abrasive erosion in turbines of hydropower plants (HPPs) at sediment-laden rivers is still a concern despite the application of hard-coatings. To further investigate the problem and support HPP operators to better cope with the fine sediment load and its consequences, a long-term research study was conducted at the high-head run-of-river HPP Fieschertal in the Swiss Alps. From 2012 to 2020, the sediment load, erosion and efficiency differences of the two 32 MW-Pelton turbines of the HPP were measured. To do so, a real-time sediment monitoring system was installed and procedures to monitor the efficiency of the turbines were implemented. In parallel, the costs of the refurbishment and replacement of the main turbine parts were tracked. The nine years of detailed data were used to optimize the HPP operation and the turbine maintenance. A key element of this optimization is to shut down the HPP in periods of exceptionally high suspended sediment concentrations (SSC). The threshold value above which the operation of this HPP becomes unprofitable, the so-called shutdown-SSC, was determined as 15 g/l (15 000 ppm). For reliable real-time measurements up to such high SSC, a Coriolis Flow and Density Meter (CFDM) has been installed at the intake in addition to a turbidimeter whose measuring range is limited to 6 g/l. The findings of this project, such as a combination of instruments for real-time SSC measurements and the procedure to determine the shutdown-SSC, can be applied to other medium- and high-head run-of-river HPPs at sediment laden waters to improve their economic and energetic efficiency.

Understanding the origins of biodiversity has been an aspiration since the days of early naturalists such as Whewell, Lyell, Humboldt, Darwin and Wallace. These pioneers already acknowledged interactions between ecological and evolutionary processes, as well as the roles of continental movements, orogeny and climate variations in shaping biodiversity patterns. As science advanced, the complexity of ecological, evolutionary, geological and climatological processes became evident in an increasingly fragmented scientific landscape. Recent developments in computer modelling now enable the strengthening of interdisciplinary fields, opening unprecedented scientific pathways. In this thesis, a novel general engine for eco-evolutionary simulations (gen3sis) is presented. The engine consists of a spatially-explicit modelling framework that enables modular implementation of multiple macroecological and macroevolutionary processes interacting across representative spatio-temporally dynamic landscapes. Applications of gen3sis shed light into long-standing enigmas of global biodiversity patterns, such as: the latitudinal diversity gradient (LDG), the pantropical diversity gradient (PDG) and the life history of cold-adapted floras. Multiple reconstructed paleolandscapes and processes (e.g. environmental filtering, biotic interactions, energetic carrying capacities, dispersal, allopatric speciation, and the evolution of stress tolerance and competitive ability) were used to simulate emergent biodiversity patterns (e.g. ,  and  diversity, past and current species ranges, and phylogenies). Conclusions are based on comparisons of simulated patterns with literature reviews and empirical data (i.e. species ranges, phylogenies and fossils) of multiple faunas and floras. Bridging ecological and evolutionary mechanisms with paleo-environments shaped by plate-tectonic movements, mountain uplifts and deep-time climate changes using gen3sis is shown to be indispensable for reconstructing the formation of many global biodiversity patterns. Energetic carrying capacity was a significant process when concurrently simulating a realistic LDG, species range size frequencies, and phylogenetic tree balance of major tetrapod groups. Differences in paleo-environmental dynamics between continents (e.g. mountain and island formation and habitat fragmentation), combined with weak niche evolution, can explain the PDG by shaping spatial and temporal patterns of species origination and extinction. Simulations matched observed distribution and phylogenetic patterns of tropical plants and animals. Geological and climatological events, combined with species interactions and the evolution of competitive and temperature tolerance traits, provide a remarkable match with observed distributions, fossil records and the phylogenetic nestedness of cold-adapted plants. This thesis moves beyond correlational approaches and provides a novel framework for formalizing and exploring multiple hypotheses and reconstructions associated with the origin of biodiversity. Model comparison with empirical data serves hindcast, which might inform biodiversity trajectories. By advancing our numeric understanding of the physical and biological processes that shape biodiversity, new and interdisciplinary tools such as gen3sis support scientists to piece together key puzzles of the Earth’s astonishing biodiversity.

Global climate change is among the most important and severe challenges the international community has ever faced. Existing evidence shows that climatic changes will have far-reaching repercussions for ecosystems and humans alike. For instance, projections expect climate change to induce mass population movements due to hazards like droughts, sea level rise, or extreme weather events, particularly in low-income countries with limited capacity to protect themselves and adapt to such climatic changes. However, these projections are largely based on extrapolations from the population at risk of experiencing adverse climatic events. The recent literature therefore highlights that projections on climate-related migration should account for the possibility that people can adapt to changing climatic conditions. This is particularly relevant for slow-onset environmental changes such as droughts, salinization, or erosion, which individuals and societies can anticipate and adapt to. This dissertation contributes to a better understanding of whether, when, and how environmental changes lead to human migration. Theoretically, I link environmental changes to individual-level migration decisions by applying the aspirations-capabilities framework. I argue that exposure to environmental changes can increase someone’s aspirations to move away, while such exposure also has the potential of eroding the capability to move. People will move if they have both the aspiration and the capability to move. If one of the two is lacking, people remain immobile. Importantly, this concept also allows to differentiate “involuntary non-migrants” who would like to move away but lack the capability to do so from “voluntary non-migrants” who could move away but do not want to. Empirically, I employ a novel, self-collected panel data set of around 1700 household heads residing along the Jamuna River in northern Bangladesh, an area affected by riverbank erosion and flooding during the yearly recurring monsoon season. Through a multi-stage clustered sampling design, I obtained a sample representative of the rural population in the case study region. In a quasi-experimental approach, I surveyed respondents at a similar baseline risk of being affected before the environmental changes occurred. By re-interviewing both affected and unaffected respondents after the environmental changes have materialized, and both those who migrated and those who stayed, I can link any differences I observe between affected and unaffected respondents to the environmental shocks. This causal link makes a major empirical contribution to the literature on environmental migration that overwhelmingly applies secondary or retrospective data. In the empirical chapter I, I examine how the populations along the Jamuna perceive environmental and climatic changes and I compare these perceptions to objectively measured data. I find that perceptions of long-term temperature changes are more in line with meteorological evidence than those of precipitation. This finding is remarkable given that most of the respondents do not know the term climate change. Further, respondents grossly overestimate the extent of erosion that has occurred in their village in the previous year. Since human behavior is shaped by their perceptions rather than by objective data, this underlines the importance of considering people’s perceptions rather than exclusively relying on natural scientific data. Chapters II and III study how affectedness by riverbank erosion and flooding influences migration aspirations and migration behavior, respectively. The results suggest that riverbank erosion has a significant positive impact on both aspirations and the likelihood of migration. The effect of flood affectedness, by contrast, remains largely insignificant. This can be linked to the important role of flooding for the livelihood cycle of riverine populations, while erosion only has negative and potentially very detrimental effects on livelihoods. Lastly, chapter IV studies immobility in the context of environmental changes. I show that a majority (83%) of those who stay put after the monsoon season qualify as “voluntary/acquiescent non-migrants”, while 17% of the non-migrants can be classified as “involuntary”. Environmental shocks increase the respondents’ migration aspirations while reducing their capability to move. Hence, they might lead to “trapped populations” – a term which describes individuals who would like to move away but cannot. This dissertation provides valuable insights of broader relevance into whether and how societies react, or could react, to slow-onset climatic changes such as sea-level rise, drought, and soil/water salinity. Moreover, the methodology developed in the project can be applied to other cases and thereby inform prediction models of future climate-induced migration. Similarly, the findings could be utilized by institutional actors at local, national, and international levels when seeking to identify policy options to increase the adaptive capacity of populations vulnerable to climatic changes – supporting both those who would like to move and those who prefer to stay put.

Changes in the hydrological cycle are among the aspects of climate change most relevant for human systems and ecosystems. Besides trends in overall wetting or drying, changes in temporal characteristics of wetting and drying are of crucial importance in determining the climate hazard posed by such changes. This is particularly the case for tropical regions, where most precipitation occurs during the rainy season and changes in rainy season onset and length have substantial consequences. Here we present projections for changes in tropical rainy season lengths for mean temperature increase of 1.5 °C and 2 °C above pre-industrial levels. Based on multi-ensemble quasi-stationary simulations at these warming levels, our analysis indicates robust changes in rainy season characteristics in large parts of the tropics despite substantial natural variability. Specifically, we report a robust shortening of the rainy season for all of tropical Africa as well as north-east Brazil. About 27% of West Africa is projected to experience robust changes in the rainy season length with a mean shortening of about 7 days under 1.5 °C. We find that changes in the temporal characteristics are largely unrelated to changes in overall precipitation, highlighting the importance of investigating both separately. Environmental Research Letters, 13 (6) ISSN:1748-9326 ISSN:1748-9318