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As of mid-2017, there were ~7500 metric tons of mass in orbit around the Earth, of which about 95% concentrated in almost 6700 intact spacecraft and orbital stages. Among them, nearly 80% were abandoned and more than 90% could not be maneuvered. The intact objects abandoned in LEO above ~650 km, i.e. with a typical residual lifetime of more than 25 years, represent the main potential mass reservoir for the generation of new detrimental orbital debris in case of mutual collisions with the existing debris environment. A practicable strategy to assess the latent long-term environmental impact of an orbiting object is to devise a ranking scheme based on simplified and reasonable inferences. Several ranking schemes have been proposed by different authors during the last decade. Various "criticality indexes" have been devised by us (at ISTI-CNR) in the last few years, and they have been applied to evaluate the environmental impact of many families of rocket bodies and selected spacecraft. A couple of the most complete indexes formulated by us are herein applied to assess the potential criticality of the most massive objects abandoned in LEO.

Under global warming, extreme events have been increasing in the last decade and are projected to increase in the future with every increment of global warming. The potential increase in compound drought and hot events may induce a complex web of impacts on societies, ecosystems, and economies, including crop failure, wildfires, and water scarcity. This is particularly concerning for Brazil, where it has been demonstrated to be vulnerable to recent extreme climate events. Using an ensemble of CORDEX-CORE simulations over Tropical Brazil, we investigate changes in compound events inresponse to changes in radiative forcing and their impact on climate extreme events, including drought and extreme heat. The simulations are conducted at a 25 km horizontal grid spacing using lateral and lower boundary forcing from three Coupled Model Intercomparison Project Phase 5 (CMIP5) climate models. Each model covers the period from 1980 to 2100 under two Radiative Concentration Pathways (RCP2.6 and RCP8.5) in the 21st-century projection period. We used observed data from the Brazilian Daily Weather Gridded Data (BR-DWGD) to evaluate the simulations and perform a quantitative assessment of areas affected by these compound events during the present day. The study finds a generally good agreement between RCM simulations and observed data, with moderate to high correlation coefficients for precipitation, though the strength of these correlations varies across different regions and seasons. The analysis emphasizes the prevalence of compound climate events during the Austral summer season and projects a significant increase in both extreme heat and drought events in the coming decades. These findings underscore Brazil’s vulnerability to compound climate events, highlighting the need for adaptive strategies and policy interventions to mitigate the socio-economic and environmental impacts across various sectors. Fil: Bettolli, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Instituto Franco-Argentino sobre Estudios del Clima y sus Impactos; Argentina Fil: Pereira Llopart, Marta. Universidade Estadual Paulista Julio de Mesquita Filho; Brasil Fil: Feldman Firpo, Mári Ândrea. Instituto Nacional de Pesquisas Espaciais; Brasil Fil: Chimborazo Guerron, Oscar V.. State University of New York; Estados Unidos Fil: Muniz Alves, Lincoln. Instituto Nacional de Pesquisas Espaciais; Brasil Fil: Avilés Añazco, Alex. Universidad de Cuenca; Ecuador Fil: Hasson, Shabeh. Universitat Hamburg; Alemania

The potential impacts of climate change on human health in sub-Saharan Africa are wide-ranging, complex, and largely adverse. The region's Indigenous peoples are considered to be at heightened risk given their relatively poor health outcomes, marginal social status, and resource-based livelihoods; however, little attention has been given to these most vulnerable of the vulnerable. This paper contributes to addressing this gap by taking a bottom-up approach to assessing health vulnerabilities to climate change in two Batwa Pygmy communities in rural Uganda. Rapid Rural Appraisal and PhotoVoice field methods complemented by qualitative data analysis were used to identify key climate-sensitive, community-identified health outcomes, describe determinants of sensitivity at multiple scales, and characterize adaptive capacity of Batwa health systems. The findings stress the importance of human drivers of vulnerability and adaptive capacity and the need to address social determinants of health in order to reduce the potential disease burden of climate change.

Waste management contributes to sustainable development since waste can be transformed into valuable resources and commodities. Moreover, it helps resolve the concerns related to the limitation and scarcity of natural resources. Improving waste management means carrying out activities such as prevention, reuse, recycling and recovery, in the perspective of circularity, to minimize waste. Some methodologies and indicators may support sustain and monitor waste, such as the material flow and cost accounting, the life cycle assessment, and the carbon and water footprint.

Abstract Mediterranean islands have the advantage of favourable climatic conditions to use different marine renewable energy sources. Remote sensing can provide data to determine wind energy production potential and observational activity to identify, assess and detect suitable points in large marine areas. In this paper, a new combined model has been developed to integrate wind speed assessment, mapping and forecasting using Sentinel 1 satellite data through images processing and Adaptive Neuro-Fuzzy Inference System and the Bat algorithm. Synthetic Aperture Radar (SAR) satellite images from the Sentinel 1 satellite have been used in order to detect offshore and nearshore wind potential. Particularly, Sentinel 1 images have been analysed by means of the SNAP software. Then, to extract data about wind speed and direction, a GIS software for mapping the wind climate has been used. This new methodology has been applied to the North-Central coasts of Sardinia Island and then focused on six main small islands of La Maddalena archipelago. Furthermore, ten Hot Spots (HSs) have been identified as interesting because of their high-energy potential and the possibility to be considered as sites for future implementation of Wind Turbine Generators (WTGs). Finally, the ten identified HS have been used as input data to train and test the proposed forecast model.

L’articolo affronta gli aspetti generali della riqualificazione energetica degli edifici esistenti, mettendo in luce come le politiche di incentivazione e la strutturazione di alcuni percorsi tecnologici abbiano prodotto un circolo vizioso del retrofit, che agisce come un freno alla diffusione delle riqualificazioni energetiche. La prima parte si focalizza sulla letteratura internazionale, isolando alcune dimensioni utili alla ricostruzione dello stato dell’arte in Italia; la seconda parte analizza le politiche nel contesto italiano, i meccanismi che ne depotenziano gli effetti e le motivazioni della assenza di interventi di riqualificazione su scala medio-grande nelle città italiane; la terza parte affronta il tema dal punto di vista dei percorsi tecnologici, mettendo in luce alcuni aspetti inerenti la difficile strutturazione del campo organizzativo del retrofit energetico e la perdurante incertezza attorno ai dispositivi di efficienza e risparmio. Nelle conclusioni vengono fornite alcune indicazioni di policy, mettendo in luce come le politiche urbane agiscano in modo più marcato sull’efficienza energetica che sul risparmio energetico, depotenziando i sistemi di incentivazione adottati su scala nazionale.

In the present work, the supercritical water gasification (SCWG) of biomass is analyzed with a view to outlining the possible thermodynamic constraints that must be taken into account to develop this new process. In particular, issues concerning the formation of solid carbon and the process heat duty are discussed. The analysis is conducted by means of a two-phase non-stoichiometric thermodynamic model, based on Gibbs free energy minimization. Results show that char formation at equilibrium only occurs at high biomass concentrations, with a strong dependence on biomass composition. As regards the process heat duty, SCWG is mostly endothermic when biomass concentration is low, although a very small amount of oxidizing agent is able to make the process exothermic, with only a small loss in the heating value of the syngas produced.

Doubly-fed induction generators (DFIGs) are widely used in wind turbine systems. Traditionally, they rely on the grid voltage to operate. However, the increasing penetration of renewables necessitates wind turbines that can contribute to grid stability, and grid-forming control (GFM) has emerged as an attractive solution. Traditionally, the GFM control of DFIGs has been proposed as a single-loop control of the rotor flux magnitude and orientation, while double-loop schemes based on virtual impedance or virtual admittance have been scarcely investigated. This paper analyzes the operation and small-signal stability of a virtual-impedance-based dual-loop GFM control for DFIG. The small-signal impedance-model is derived and used to analyze the system stability in case of strong and weak grid connection. Electromagnetic transient simulations on a 1.5 MW wind turbine system are presented to validate the analysis.