Description: The steel industry is responsible for eight per cent of global CO2 emissions. As more than seven out of ten of today's coal-fired blast furnaces are due to be refurbished or replaced in the 2020s, there is a key window of opportunity to shift to low-emission production methods before the end of this decade. The analysis by Agora Industry, Wuppertal Institute and Lund University assesses eight potential breakthrough technologies in terms of their market readiness, cost and impact on emissions. The methods analysed include the use of hydrogen to produce direct reduced iron, scrap-based electric arc furnaces, electrolysis and the implementation of carbon capture in existing coal-fired facilities. While some of these technologies can already be deployed today to kick-start the market for green steel, others will take more time to reach technological maturity, but show promise in the long-term. A third group may never turn into adequate solutions for decarbonising the steel sector. In their analysis, the scientists conclude that scrap and hydrogen-based methods hold the biggest promise for companies aiming to make the switch this decade. By contrast, retrofitting existing coal-based facilities with carbon capture and storage (CCS) technology entails the biggest economic and environmental risk, the authors find. Regardless of the technologies chosen, appropriate regulatory frameworks, international cooperation, and targeted incentives are necessary to boost demand for green steel and promote its production. At the same time, such measures can help steer manufacturers away from costly technological dependencies.

Description: Tropical coastal benthic communities will change in species composition and relative dominance due to global (e.g., increasing water temperature) and local (e.g., increasing terrestrial influence due to land-based activity) stressors. This study aimed to gain insight into possible trajectories of coastal benthic assemblages in Raja Ampat, Indonesia, by studying coral reefs at varying distances from human activities and marine lakes with high turbidity in three temperature categories (〈31 °C, 31–32 °C, and 〉32 °C). The benthic community diversity and relative coverage of major benthic groups were quantified via replicate photo transects. The composition of benthic assemblages varied significantly among the reef and marine lake habitats. The marine lakes 〈31 °C contained hard coral, crustose coralline algae (CCA), and turf algae with coverages similar to those found in the coral reefs (17.4–18.8% hard coral, 3.5–26.3% CCA, and 15–15.5% turf algae, respectively), while the higher temperature marine lakes (31–32 °C and 〉32 °C) did not harbor hard coral or CCA. Benthic composition in the reefs was significantly influenced by geographic distance among sites but not by human activity or depth. Benthic composition in the marine lakes appeared to be structured by temperature, salinity, and degree of connection to the adjacent sea. Our results suggest that beyond a certain temperature (〉31 °C), benthic communities shift away from coral dominance, but new outcomes of assemblages can be highly distinct, with a possible varied dominance of macroalgae, benthic cyanobacterial mats, or filter feeders such as bivalves and tubeworms. This study illustrates the possible use of marine lake model systems to gain insight into shifts in the benthic community structure of tropical coastal ecosystems if hard corals are no longer dominant.

Description: The evolution of the Pontocaspian lakes and seas (Caspian Sea, Black Sea, Aral Sea) is characterised by major changes in water levels, which developed into a pulsating system of connected and isolated basins. During the late Quaternary (Late Pleistocene and Holocene), these basins have hosted a unique endemic biodiversity that experienced species turnover events. There are indications that the Pontocaspian species diversity is now in demise because of anthropogenic modifications of the ecosystem, such as habitat alteration, poaching, pollution and invasive species. Little data is available on faunal changes and resilience of Pontocaspian species to help discerning the effect of natural drivers and anthropogenic drivers on the endemic fauna, which is of direct relevance for conservation strategies. \nThis thesis aims to characterize species richness and abundance of fossil faunas to establish a baseline for comparison with the changing biodiversity of today. Mollusc species are used as the study group as they easily fossilize and are abundant in the geological record. They inform us about the composition of communities and how they change, and enable us to reconstruct environments (\xe2\x80\x98habitats\xe2\x80\x99). This is necessary in order to compare biodiversity through different time intervals and establish whether comparable habitats existed as those of today. A baseline of Pontocaspian mollusc faunas was achieved by analysing snapshots from the Caspian Sea basin and the Black Sea basin. Caspian mollusc assemblages are analysed from late Pleistocene (corresponding to the late Khazarian, Hyrcanian, early Khvalynian and late Khvalynian regional stages) and pre-20th century Holocene (Novocaspian) assemblages. Black Sea assemblages from the late Neoeuxinian and late Holocene are described. They are both compared with modern day assemblages. \nThis study shows clear indications of a Pontocaspian mollusc diversity crisis. Overall, in the 20th\xe2\x80\x9321st century, Pontocaspian molluscs have experienced a severe decline in species richness and abundance: a strong turnover towards invasive species in the Caspian basin, a strong habitat decline in parts of the Black Sea basin and a total obliteration in the Aral basin. The late Quaternary mollusc fauna snapshots demonstrate that endemic species dominated the Caspian communities with minor contributions of native species until the late Holocene. The Pontocaspian mollusc species richness in the Caspian Sea basin is higher than in the Pontocaspian habitats of the Black Sea basin, or the Aral Sea basin. Throughout the Late Quaternary, the strong natural fluctuations of Caspian Sea level affected shallow water bivalve species of the genus Didacna, but barely changed the overall composition of the mollusc faunas. Late Quaternary mollusc fauna snapshots of the Black Sea basin show very little change in the Pontocaspian species community since humans impacted the habitats. However, the Black Sea Pontocaspian mollusc communities are currently under severe threat of habitat deterioration and destruction. \nThis research indicates that the Caspian Sea could act as a source for Pontocaspian biota, hence conservation efforts are imperative there. The deeper parts (〉50 m water depth) possibly present a (partial) refuge, and urgent research is required to assess these habitats and their faunas. Future research should focus on improving the taxonomic framework to elucidate the identity of some Pontocaspian cryptic and sister species. We need more distribution and ecological data of current Pontocaspian species and more detailed biodiversity time series coupled with detailed environmental proxies to assess the nature of the Pontocaspian biodiversity crisis more comprehensively and plan conservation actions accordingly.

Description: In the energy sector, few topics, if any, are more hyped than hydrogen. Countries develop hydrogen strategies to provide a perspective for hydrogen production and use in order to meet climate-neutrality goals. However, in this topical field the role of water is less accentuated. Hence, in this study, we seek to map the interrelations between the water and wastewater sector on the one hand and the hydrogen sector on the other hand, before reflecting upon our findings in a country case study. We chose the Hashemite Kingdom of Jordan because (i) hydrogen is politically discussed not least due to its high potentials for solar PV, and (ii) Jordan is water stressed - definitely a bad precondition for water-splitting electrolyzers. This research is based on a project called the German-Jordanian Water-Hydrogen-Dialogue (GJWHD), which started with comprehensive desk research mostly to map the intersectoral relations and to scope the situation in Jordan. Then, we carried out two expert workshops in Wuppertal, Germany, and Amman, Jordan, in order to further discuss the nexus by inviting a diverse set of stakeholders. The mapping exercise shows various options for hydrogen production and opportunities for planning hydrogen projects in water-scarce contexts such as Jordan.

Description: Direct air capture (DAC) combined with subsequent storage (DACCS) is discussed as one promising carbon dioxide removal option. The aim of this paper is to analyse and comparatively classify the resource consumption (land use, renewable energy and water) and costs of possible DAC implementation pathways for Germany. The paths are based on a selected, existing climate neutrality scenario that requires the removal of 20 Mt of carbon dioxide (CO2) per year by DACCS from 2045. The analysis focuses on the so-called "low-temperature" DAC process, which might be more advantageous for Germany than the "high-temperature" one. In four case studies, we examine potential sites in northern, central and southern Germany, thereby using the most suitable renewable energies for electricity and heat generation. We show that the deployment of DAC results in large-scale land use and high energy needs. The land use in the range of 167-353 km2 results mainly from the area required for renewable energy generation. The total electrical energy demand of 14.4 TWh per year, of which 46% is needed to operate heat pumps to supply the heat demand of the DAC process, corresponds to around 1.4% of Germany's envisaged electricity demand in 2045. 20 Mt of water are provided yearly, corresponding to 40% of the city of Cologne's water demand (1.1 million inhabitants). The capture of CO2 (DAC) incurs levelised costs of 125-138 EUR per tonne of CO2, whereby the provision of the required energy via photovoltaics in southern Germany represents the lowest value of the four case studies. This does not include the costs associated with balancing its volatility. Taking into account transporting the CO2 via pipeline to the port of Wilhelmshaven, followed by transporting and sequestering the CO2 in geological storage sites in the Norwegian North Sea (DACCS), the levelised costs increase to 161-176 EUR/tCO2. Due to the longer transport distances from southern and central Germany, a northern German site using wind turbines would be the most favourable.

Description: The development of digital technologies is accelerating, enabling increasingly profound changes in increasingly short time periods. The changes affect almost all areas of the economy as well as society. The energy sector has already seen some effects of digitalization, but more drastic changes are expected in the next decades. Besides the very positive impacts on costs, system stability, and environmental effects, potential obstacles and risks need to be addressed to ensure that advantages can be exploited while adverse effects are avoided. A good understanding of available and future digital applications from different stakeholders' perspectives is necessary. This study proposes a framework for the holistic evaluation of digital applications in the energy sector. The framework consists of a combination of well-established methods, namely the multi-criteria analysis (MCA), the life cycle assessment (LCA), and expert interviews. The objective is to create transparency on benefits, obstacles, and risks as a basis for societal and political discussions and to supply the necessary information for the sustainable development and implementation of digital applications. The novelty of the proposed framework is the specific combination of the three methods and its setup to enable sound applicability to the wide variety of digital applications in the energy sector. The framework is tested subsequently on the example of the German smart meter roll-out. The results reveal that, on the one hand, the smart meter roll-out clearly offers the potential to increase the system stability and decrease the carbon emission intensity of the energy system. Therefore, the overall evaluation from an environmental perspective is positive. However, on the other hand, close attention needs to be paid to the required implementation and operational effort, the IT (information technology) and data security, the added value for the user, the social acceptance, and the realization of energy savings. Therefore, the energy utility perspective in particular results in an overall negative evaluation. Several areas with a need for action are identified. Overall, the proposed framework proves to be suitable for the holistic evaluation of this digital application.

Description: The demand for metals from the entire periodic table is currently increasing due to the ongoing digitalization. However, their use within electrical and electronic equipment (EEE) poses problems as they cannot be recovered sufficiently in the end-of-life (EoL) phase. In this paper, we address the unleashed dissipation of metals caused by the design of EEE for which no globally established recycling technology exists. We describe the European Union's (EU) plan to strive for a circular economy (CE) as a political response to tackle this challenge. However, there is a lack of feedback from a design perspective. It is still unknown what the implications for products would be if politics were to take the path of a CE at the level of metals. To provide clarification in this respect, a case study for indium is presented and linked to its corresponding recycling-metallurgy of zinc and lead. As a result, a first material-specific rule on the design of so-called "anti-dissipative" products is derived, which actually supports designing EEE with recycling in mind and represents an already achieved CE on the material level. In addition, the design of electrotechnical standardization is being introduced. As a promising tool, it addresses the multi-dimensional problems of recovering metals from urban ores and assists in the challenge of enhancing recycling rates. Extending the focus to other recycling-metallurgy besides zinc and lead in further research would enable the scope for material-specific rules to be widened.

Description: Food and nutrition systems are linked to all Sustainable Development Goals (SDGs), which makes their transition toward social-ecological behavior patterns crucial for an overarching sustainability transformation. The perspective of (urban) logistics is of special interest. It couples the production and consumption physically and virtually. In this context, we shed light on the design of the turnover point of food in urban areas from the supply chain toward consumers and contribute to an overarching systemic perspective toward establishing a sustainable multilevel food system. We describe current patterns in urban food systems and propose several principles for sustainable design of (urban) food systems based on concepts such as (regional) collaboration and food literacy. Using these principles, we provide four design scenarios that concretely imagine future urban food consumption and production patterns titled "slow stock supply service," "deliver into the daily walk," "central district food depot," "super food action place." With this work we provide a starting for reflecting whether certain combinations of principles actually lead to patterns of daily life that are feasible, acceptable, or desirable. Moreover, we provide an initial qualitative assessment to stimulate further research that explores scenario pathways and incorporates additional indicators regarding the impact on social-ecological. We open up various research questions with regard to the overarching question of how urban food logistics should be designed to be consistent with the SDGs.

Description: A clear understanding of socio-technical interdependencies and a structured vision are prerequisites for fostering and steering a transition to a fully renewables-based energy system. To facilitate such understanding, a phase model for the renewable energy (RE) transition in the Middle East and North Africa (MENA) countries has been developed and applied to the country case of Jordan. It is designed to support the strategy development and to serve as a guide for decision-makers. The analysis shows that Jordan has taken essential steps towards a RE transition. According to the MENA energy transition phase model, Jordan can be classified as being in a transitional stage between the first phase, "Take-Off Renewables", and the second phase, "System Integration". However, fossil fuels continue to play a dominant role in the Jordanian energy sector, and the fluctuating world market prices for fossil fuels impact the economy. The expansion of domestically produced RE could significantly contribute to reducing Jordan's high imports of fossil fuels. This simultaneously increases energy security and reduces the trade deficit. To move towards a sustainable energy system, Jordan needs to embrace comprehensive flexibility measures. These include developing storage options, improving load management, upgrading the existing grid infrastructure, enhancing energy efficiency, exploring the electrification of end use sectors, and creating strong cooperation between stakeholders.

Description: The food system faces a multitude of challenges, including high greenhouse gas emissions, threats to biodiversity, increased diet-related diseases due to unbalanced diets, and socially problematic complex supply chains. This requires not only a transformation of the agricultural economy but also a change in the diet and lifestyles of all consumers. Developing and using digital and technological innovations can help to solve these challenges. In this context, the study provides impulses on how digitalisation can contribute to transforming production and consumption and which prerequisites have to be given to achieve this. The study describes the approaches for digitalisation along the value chain. These include optimising the use of resources in agriculture - for example with the help of smart farming - and supporting consumers with digital tools and assistance systems - such as apps designed to support grocery shopping. In addition, new business models and a better connection between production and consumption processes are also possible. This includes, for example, new digital sales channels or tracking and communicating sustainability indicators such as CO2 emissions across all steps of the value chain in order to enable all stakeholders to take reliable action.