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This paper aims to update our understanding of the carbon cycle in the Himalayas, the most intense collisional orogeny globally, by providing new insight into its impact on Cenozoic climate cooling through the use of isotopic variations in both organic and inorganic carbon and an isotopic mass balance model. Our results from 20 selected hot springs show that the relative contributions of dissolved carbon from the mantle, metamorphic decarbonization, aqueous dissolution, and soil organic matter are approximately 2%, 82%, 6%, and 10%, respectively. Approximately 87% ± 5% of CO2 generated in the deep crust precipitates as calcite, while approximately 5.5% ± 1% of this carbon is converted to biomass through microbial chemosynthesis at depths less than 2 km. Our random forests approach yielded a metamorphic carbon flux from the entire Himalayan orogenic belt of approximately 2.7 ∼ 4.5 × 1012 mol/yr. The minor CO2 released into the atmosphere (2.5 ∼ 4.2 × 1011 mol/yr) is comparable to the carbon consumption driven by Himalayan weathering. This paper provides new insights into deep carbon cycling, notably that approximately 93% of deeply sourced carbon is trapped in the shallow crust, rendering orogenic processes carbon neutral and possibly acting as one of the major triggers of long‐term climate cooling in the Cenozoic. Plain Language Summary: Large‐scale deep metamorphic decarbonization and CO2 release into the atmosphere during continental collision orogenesis worldwide have had significant impacts on Cenozoic global climate change. However, the carbon sources and sinks and the mechanisms underlying their impacts on climate change are not fully understood. This paper reports the chemistry of aqueous solutions, carbon isotopic compositions of dissolved inorganic carbon (DIC) and dissolved organic carbon (DOC), and helium and carbon isotopic compositions of free gases from hot springs in southern Tibet. The carbon isotope fractionation model between gas and aqueous solutions revealed that the carbon released from depth underwent six different stages. Based on the random forests machine learning algorithm, we estimated the metamorphic carbon flux across the Himalayan orogenic belt. Furthermore, only a small fraction (7%) of deep carbon is eventually released into the atmosphere, and this volume is the same magnitude as the amount of carbon absorbed by silicate weathering on the Tibetan Plateau. This paper emphasizes that the carbon sequestration process in the upper crust may have resulted in nearly carbon‐neutral geological bodies in the Himalayan orogenic belt, thus playing a critical role in Cenozoic climate cooling. Key Points: Approximately 87% of deeply sourced carbon precipitates as calcite, while approximately 5.5% is sequestered as biomass in the shallow crustThe carbon flux across the Himalayan orogenic belt was estimated by the random forests approachCrustal thickening has attenuated long‐term deep carbon emissions from the Himalayas [ABSTRACT FROM AUTHOR]

Summary: The dedication of the international anaesthetic community to reducing the environmental impact of healthcare is important and to be celebrated. When this is underpinned by robust science, it has the potential to make a real difference. However, volatile anaesthetic agents have been widely promoted in the medical literature as damaging to the climate, leading to a drive to remove them from clinical practice. This is based on notional 'CO2‐equivalent' values created using the simple emission metric known as the global warming potential. Here, we assert that when proper consideration is given to the science of climate change, volatile anaesthetic gas emissions cannot be simply equated to real carbon dioxide emissions, and that their climate impact is vanishingly small. This paper gives anaesthetists a framework to make informed choices founded on climate science and calls for attention to be refocused on the urgent need to reduce the real carbon dioxide emissions associated with healthcare. [ABSTRACT FROM AUTHOR]

In recent years, the amount of the photovoltaic (PV) system has been rapidly increasing from the viewpoint of carbon neutral. There are concerns about voltage rises and grid congestion in the electrical distribution network because of large‐scale PV increases. In order to address these issues, we focused on the control of water supply pumps in the water distribution system, which is infrastructure equipment for consumers. By controlling the start/stop of the water pump, it is expected to contribute to the power distribution system by increasing Demand Response (DR) and reduce CO2 emission from the electricity used by the pump. In this paper, with the aim of constructing an optimal operation planning method for water pumps that can evaluate DR and CO2 reduction effects, the optimal operation plan is formulated as a mixed integer linear programming problem. We numerical evaluated impact of water pump operation for CO2 emission and electrical distribution network. © 2023 The Authors. IEEJ Transactions on Electrical and Electronic Engineering published by Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

The marine biological carbon pump (BCP) stores carbon in the ocean interior, isolating it from exchange with the atmosphere and thereby coregulating atmospheric carbon dioxide (CO2). As the BCP commonly is equated with the flux of organic material to the ocean interior, termed "export flux," a change in export flux is perceived to directly impact atmospheric CO2, and thus climate. Here, we recap how this perception contrasts with current understanding of the BCP, emphasizing the lack of a direct relationship between global export flux and atmospheric CO2. We argue for the use of the storage of carbon of biological origin in the ocean interior as a diagnostic that directly relates to atmospheric CO2, as a way forward to quantify the changes in the BCP in a changing climate. The diagnostic is conveniently applicable to both climate model data and increasingly available observational data. It can explain a seemingly paradoxical response under anthropogenic climate change: Despite a decrease in export flux, the BCP intensifies due to a longer reemergence time of biogenically stored carbon back to the ocean surface and thereby provides a negative feedback to increasing atmospheric CO2. This feedback is notably small compared with anthropogenic CO2 emissions and other carbon‐climate feedbacks. In this Opinion paper, we advocate for a comprehensive view of the BCP's impact on atmospheric CO2, providing a prerequisite for assessing the effectiveness of marine CO2 removal approaches that target marine biology. [ABSTRACT FROM AUTHOR]

This paper examines how global trade shapes and intensifies disasters. Juxtaposing three basic, everyday consumer goods – a t‐shirt, a brick, and a tea bag – with disasters manifesting in their respective global supply chains, it highlights how climate change, local environmental degradation, and carbon emissions are dynamically shaped by consumption. Analysis of data collected in South and Southeast Asia reveals that local environmental degradation linked to international trade interacts with global climate change and the policies intended to mitigate it, influencing how and where disasters manifest. Underpinning this analysis is the physical and conceptual presence of the container. With more and more of the natural environment packaged and redistributed for global trade, the container thinking that underpins these logistics is increasingly imbricated in environmental processes. Indeed, as this paper aims to show, the container logic that frames analysis of these processes – linked to and drawn from the logistics of global trade – serves as both obfuscator and actor in the global landscape of environmental risk. [ABSTRACT FROM AUTHOR]

In near future, the main challenge is to reduce the use of fossil fuels that currently emit the bulk of global CO2 emissions, responsible of the global warming and climate change. Hydrogen, as a future fuel candidate, would play a significant role for net‐zero emission requirements. As a matter of fact, new hydrogen tank design is needed to bring this technology to the readiness level. This paper aims to investigate on the impact resistance of a hybrid aluminum‐composite hydrogen tank. In particular, the paper presents the development of two finite element (FE) models for the simulation of two impact scenarios experimentally investigated and proposed in literature. The models provided acceptable levels of accuracy with consequent benefits in supporting designers in the certification process of such device type. [ABSTRACT FROM AUTHOR]