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  • Other
    Murray-Watson RJ, Gryspeerdt E, 2024,

    Supplementary material to "Air mass history linked to the development of Arctic mixed-phase clouds"

  • Journal article
    Shi J, Feng X, Toumi R, Zhang C, Hodges KI, Tao A, Zhang W, Zheng Jet al., 2024,

    Publisher Correction: Global increase in tropical cyclone ocean surface waves.

    , Nat Commun, Vol: 15
  • Journal article
    Nielsen PY, Jensen MK, Mitarai N, Bhatt Set al., 2024,

    The Gompertz Law emerges naturally from the inter-dependencies between sub-components in complex organisms.

    , Sci Rep, Vol: 14

    Understanding and facilitating healthy aging has become a major goal in medical research and it is becoming increasingly acknowledged that there is a need for understanding the aging phenotype as a whole rather than focusing on individual factors. Here, we provide a universal explanation for the emergence of Gompertzian mortality patterns using a systems approach to describe aging in complex organisms that consist of many inter-dependent subsystems. Our model relates to the Sufficient-Component Cause Model, widely used within the field of epidemiology, and we show that including inter-dependencies between subsystems and modeling the temporal evolution of subsystem failure results in Gompertizan mortality on the population level. Our model also provides temporal trajectories of mortality-risk for the individual. These results may give insight into understanding how biological age evolves stochastically within the individual, and how this in turn leads to a natural heterogeneity of biological age in a population.

  • Journal article
    Whitmee S, Green R, Belesova K, Hassan S, Cuevas S, Murage P, Picetti R, Clercq-Roques R, Murray K, Falconer J, Anton B, Reynolds T, Sharma Waddington H, Hughes RC, Spadaro J, Aguilar Jaber A, Saheb Y, Campbell-Lendrum D, Cortés-Puch M, Ebi K, Huxley R, Mazzucato M, Oni T, de Paula N, Peng G, Revi A, Rockström J, Srivastava L, Whitmarsh L, Zougmoré R, Phumaphi J, Clark H, Haines Aet al., 2024,

    Pathways to a healthy net-zero future: report of the Lancet Pathfinder Commission.

    , Lancet, Vol: 403, Pages: 67-110
  • Journal article
    Desouza C, Marsh D, Beevers S, Molden N, Green Det al., 2024,

    Emissions from the construction sector in the United Kingdom

    , Emission Control Science and Technology, ISSN: 2199-3637

    The UK national atmospheric emissions inventory estimates of construction industry emissions use a top-down approach, based on fuel consumption and employment. It estimates that the sector is the 2nd largest emitter of PM2.5 (14%) and 4th largest emitter of NOX (7%). In this study, we have adopted a bottom-up approach to assess emissions of NOX from the sector and show that emissions are 39% higher than the existing estimates. By developing a novel fleet turnover model to predict the population and emission standard of construction machinery up to 2025, we demonstrate a significant shift in the quantity and types of machines used. The overall uncertainty of the model was calculated to be 55%. Applying the estimated uncertainties to the model, in 2018, the non-road mobile machinery fleet in the UK emitted 36.6 ± 10.0 kilo-tonnes of NOX, whilst the NAEI estimated 33.2 kilo-tonnes for the same sector. For the subsequent years 2019 and 2020, the NAEI estimate was within the model’s uncertainty prediction—28.0 kilo-tonnes compared with 32.7 ± 8.9 kilo-tonnes for 2019 and 23.2 kilo-tonnes compared with 29.5 ± 8.1 kilo-tonnes for 2020. Overall, the size of the non-road mobile machinery fleet in the UK is predicted to reduce by 4% in 2025 compared to 2018. Furthermore, the introduction of Stages IV and V emission regulations for new machines will lead to a 58% reduction in fleet NOX emissions over the same period. These emission regulations are targeted at the larger, more polluting machines, with smaller machines not required to meet tighter emissions standards under Stage V. As a result, mini-excavators are the most common machines and consequently become the dominant source of NOX emissions from the fleet, contributing 55% in 2025. Therefore, tighter emissions regulations, or the uptake of battery power in the form of electrification, for these small machines would yield significant emissions redu

  • Journal article
    Shi J, Feng X, Toumi R, Zhang C, Hodges KI, Tao A, Zhang W, Zheng Jet al., 2024,

    Global increase in tropical cyclone ocean surface waves.

    , Nat Commun, Vol: 15

    The long-term changes of ocean surface waves associated with tropical cyclones (TCs) are poorly observed and understood. Here, we present the global trend analysis of TC waves for 1979-2022 based on the ERA5 wave reanalysis. The maximum height and the area of the TC wave footprint in the six h reanalysis have increased globally by about 3%/decade and 6%/decade, respectively. The TC wave energy transferred at the interface from the atmosphere to the ocean has increased globally by about 9%/decade, which is three times larger than that reported for all waves. The global energy changes are mostly driven by the growing area of the wave footprint. Our study shows that the TC-associated wave hazard has increased significantly and these changes are larger than those of the TC maximum wind speed. This suggests that the wave hazard should be a concern in the future.

  • Journal article
    Jagtap SS, Childs PRN, Stettler MEJ, 2024,

    Performance sensitivity of subsonic liquid hydrogen long-range tube-wing aircraft to technology developments

    , International Journal of Hydrogen Energy, Vol: 50, Pages: 820-833, ISSN: 0360-3199

    Liquid hydrogen (LH2) may enable the decarbonisation of long-haul aviation. However, its low volumetric energy density and subsequent tank space and weight requirements could penalise an aircraft's specific energy consumption (SEC, MJ/tonne-km). We evaluate the impacts of developments in four technology areas – aerodynamics, structures, cryo-tank gravimetric index (η), and overall efficiency (ηo) – on the design-point performance of a large subsonic tube-wing LH2 aircraft. We characterise the critical value of η, which must be exceeded to enable a given design range. For a design range of 14,000 km, η must exceed 0.52 today but only 0.35 with expected 2030 airframe and engine efficiency improvements. Using the most optimistic technology development estimates we observe that SEC could reduce by ∼25% via improvements in ηo and aerodynamics and by 33% via improvements in all four areas. Developments in technologies to improve ηo and reduce drag are critical to enabling zero-carbon long-haul air travel.

  • Book
    Zimmerman RW, Paluszny A, 2024,

    Fluid Flow in Fractured Rocks

    , ISBN: 9781119248019

    “The definitive treatise on the subject for many years to come” (Prof. Ruben Juanes, MIT) Authoritative textbook that provides a comprehensive and up-to-date introduction to fluid flow in fractured rocks Fluid Flow in Fractured Rocks provides an authoritative introduction to the topic of fluid flow through single rock fractures and fractured rock masses. This book is intended for readers with interests in hydrogeology, hydrology, water resources, structural geology, reservoir engineering, underground waste disposal, or other fields that involve the flow of fluids through fractured rock masses. Classical and established models and data are presented and carefully explained, and recent computational methodologies and results are also covered. Each chapter includes numerous graphs, schematic diagrams and field photographs, an extensive reference list, and a set of problems, thus providing a comprehensive learning experience that is both mathematically rigorous and accessible. Written by two internationally recognized leaders in the field, Fluid Flow in Fractured Rocks includes information on: Nucleation and growth of fractures in rock, with a multiscale characterization of their geometric traits Effect of normal and shear stresses on the transmissivity of a rock fracture and mathematics of fluid flow through a single rock fracture Solute transport in rocks, with quantitative descriptions of advection, molecular diffusion, and dispersion Fluid Flow in Fractured Rocks is an essential resource for researchers and postgraduate students who are interested in the field of fluid flow through fractured rocks. The text is also highly suitable for professionals working in civil, environmental, and petroleum engineering.

  • Journal article
    Boulton SJ, Rodés Á, Fabel D, Alçiçek MC, Whittaker ACet al., 2024,

    Complex erosional response to uplift and rock strength contrasts in transient river systems crossing an active normal fault revealed by <sup>10</sup>Be and <sup>26</sup>Al cosmogenic nuclide analyses

    , Earth Surface Processes and Landforms, ISSN: 0197-9337

    Understanding the influence of bedrock lithology on the catchment-averaged erosion rates of normal fault-bounded catchments and the effect that different bedrock erodibilties have on the evolution of transient fluvial geomorphology remain major challenges. To investigate this problem, we collected 18 samples for 10Be and 26Al cosmogenic nuclide analysis to determine catchment-averaged erosion rates along the well-constrained Gediz Fault system in western Türkiye, which is experiencing fault-driven river incision owing to a linkage event ~0.8 Ma and has weak rocks overlying strong rocks in the footwall. Combined with existing cosmogenic data, we show that the background rate of erosion of the pre-incision landscape can be constrained as <92 mMyr−1, and erosion rates within the transient reach vary from 16 to 1330 mMyr−1. Erosion rates weakly scale with unit stream power, steepness index and slip rate on the bounding fault, although erosion rates are an order of magnitude lower than slip rates. However, there are no clear relationships between erosion rate and relief or catchment slope. Bedrock strength is assessed using Schmidt hammer rebound and Selby Rock Mass Strength Assessments; despite a 30-fold difference in erodibility, there is no difference in the erosion rate between strong and weak rocks. We argue that, for the Gediz Graben, the strong lithological contrast affects the ability of the river to erode the bed, resulting in a complex erosional response to uplift along the graben boundary fault. Weak covariant trends between erosion rates and various topographic factors potentially result from incomplete sediment mixing or pre-existing topographic inheritance. These findings indicate that the erosional response to uplift along an active normal fault is a complex response to multiple drivers that vary spatially and temporally.

  • Journal article
    Tsui EYL, Chan PW, Toumi R, 2024,

    Boundary layer profile of decaying and non-decaying tropical storms near landfall

    , Atmospheric Science Letters, Vol: 25, ISSN: 1530-261X

    The vertical profile of the wind structure of translating tropical cyclones, including the associated azimuthal asymmetry, has been the subject of existing theoretical and observational studies using dropsondes. Most of these studies are based on data collected from relatively strong cyclones over the Atlantic. Here we explore the tropical cyclone boundary layer wind profile of mainly relatively weak landfalling cyclones near Hong Kong. We find that decaying tropical storms have a much larger mid- to low-level inflow angle than those that are intensifying or in steady-state. The inflow angles of intensifying, steady-state and decaying tropical storms converge towards the top of the boundary layer. The wind speed reduces through the boundary layer in a similar way in all three cases. The combination of these factors means that decaying tropical storms have stronger inflow than intensifying and steady-state ones. We attribute these local effects to remote enhanced surface friction over land when the storms are weakening.

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