Identifying robust response options to manage environmental change using an ecosystem approach:a stress-testing case study for the UK

A diverse range of response options was evaluated in terms of their utility for sustaining ecosystem services in the UK. Robustness of response options was investigated by applying a ‘stress-testing’ method which evaluated expected performance against combined scenarios of socioeconomic and climate change. Based upon stakeholder feedback, a reference scenario representing current trends in climate and socioeconomic drivers (‘business-as-usual’) was used as a dynamic baseline against which to compare results of other scenarios. The robustness of response options was evaluated by their utility in different environmental and social contexts as represented by the scenarios, and linked to their adaptability to adjust to changing conditions. Key findings demonstrate that adaptability becomes increasingly valuable as the magnitude and rate of future change diverges from current trends. Stress-testing also revealed that individual responses in isolation are unlikely to be robust meaning there are advantages from integrating cohesive combinations (bundles) of response options to maximise their individual strengths and compensate for weaknesses. This identifies a role for both top-down and bottom-up responses, including regulation, spatial targeting, incentives and partnership initiatives, and their use in combination through integrated assessment and planning consistent with the adoption of an Ecosystem Approach. Stress-testing approaches can have an important role in future-proofing policy appraisals but important knowledge gaps remain, especially for cultural and supporting ecosystem services. Finally, barriers and enablers to the implementation of more integrated long-term adaptive responses were identified drawing on the ‘4 Is’ (Institutions, Information, Incentives, Identity) conceptual framework. This highlighted the crucial but usually understated role of identity in promoting ownership and uptake of responses

Sand, salt, and models : The legacy of Bruno Vendeville

Acknowledgements We are grateful for the support of numerous colleagues who contributed, either materially or simply with encouragement, to putting together this memorial to our friend Bruno. The important task of reviewing and editing manuscripts was carried out by the co-editors along with Jürgen Adam, Ian Davison, Tim Dooley, Carl Fiduk, Pablo Granado, Geoffroy Mohn, Webster Mohriak, Van Mount, Josep Anton Muñoz, Thierry Nalpas, Fabrizio Storti, Gabor Tari, Lei Wu, and 16 reviewers who chose to remain anonymous. And of course, this volume would not have happened without the hard work and persistence of the many authors and coauthors who contributed their manuscripts. We also thank Lorna Stewart and other staff at the Journal of Structural Geology for their help and guidance, as well as Tim Dooley for supplying original versions of the figures used here.Peer reviewe

The Sloan Digital Sky Survey: The Cosmic Spectrum and Star-Formation History

We present a determination of the `Cosmic Optical Spectrum' of the Universe, i.e. the ensemble emission from galaxies, as determined from the red-selected Sloan Digital Sky Survey main galaxy sample and compare with previous results of the blue-selected 2dF Galaxy Redshift Survey. Broadly we find good agreement in both the spectrum and the derived star-formation histories. If we use a power-law star-formation history model where star-formation rate $\propto (1+z)^\beta$ out to z=1, then we find that $\beta$ of 2 to 3 is still the most likely model and there is no evidence for current surveys missing large amounts of star formation at high redshift. In particular `Fossil Cosmology' of the local universe gives measures of star-formation history which are consistent with direct observations at high redshift. Using the photometry of SDSS we are able to derive the cosmic spectrum in absolute units (i.e.$W \AA$^{-1}$Mpc$^{-3}$) at 2--5\AA resolution and find good agreement with published broad-band luminosity densities. For a Salpeter IMF the best fit stellar mass/light ratio is 3.7--7.5$\Msun/\Lsun$in the r-band (corresponding to$\omstars h = 0.0025$--0.0055) and from both the stellar emission history and the H$\alpha$luminosity density independently we find a cosmological star-formation rate of 0.03--0.04 h$\Msun$yr$^{-1}$Mpc$^{-3}$ today.Comment: 17 pages, 11 figures, ApJ in press (April 10th 2003

Influence of overlapping décollements, syn-tectonic sedimentation and structural inheritace in the evolution of contractional system: The central Kuqa fold-and-thrust bely (Tian Shan Mountains, NW China)

Contractional deformation in the Kuqa fold‐and‐thrust belt (southern foreland of the Tian Shan Mountains, NW China) is recorded by well‐preserved syntectonic continental sequences. In addition, its structural evolution was strongly controlled by synorogenic salt (Eocene in age) and presalt décollements with varying spatial distribution. We present a balanced and sequentially restored cross section across the central part of this fold‐and‐thrust belt that provides a new interpretation of the structure beneath the evaporites, in which Paleozoic and Mesozoic strata are deformed by a thrust stack involving (i) a thin‐skinned thrust system detached on Triassic‐Jurassic coal units and (ii) an ensemble of south‐directed basement thrusts. The latter formed from the inversion of Mesozoic extensional faults such as those preserved both in the Tarim foreland basin and beneath the frontal part of the Kuqa fold‐and‐thrust belt. The constructed section shows a total shortening of 35 km from the Late Cretaceous to the present. The restoration depicts a three‐stage evolution for the Kuqa fold‐and‐thrust belt: (i) minor Mesozoic extension, (ii) an early compressional stage (Late Cretaceous to early Miocene) with low shortening and syntectonic sedimentary rates, and (iii) a later compressional stage (late Pliocene‐Pleistocene) characterized by a greater and progressively increasing shortening rate and rapid deposition. Our results are discussed in light of previous analogue and numerical modeling studies and demonstrate the control exerted by the interplay between syntectonic sedimentation, the inversion of inherited basement structures, and the nature and extent of Triassic/Jurassic and Eocene décollements

Simulations of the star-forming molecular gas in an interacting M51-like galaxy: cloud population statistics

To investigate how molecular clouds react to different environmental conditions at a galactic scale, we present a catalogue of giant molecular clouds resolved down to masses of $\sim 10$~M$_{\odot}$ from a simulation of the entire disc of an interacting M51-like galaxy and a comparable isolated galaxy. Our model includes time-dependent gas chemistry, sink particles for star formation and supernova feedback, meaning we are not reliant on star formation recipes based on threshold densities and can follow the physics of the cold molecular phase. We extract giant molecular clouds at a given timestep of the simulations and analyse their properties. In the disc of our simulated galaxies, spiral arms seem to act merely as snowplows, gathering gas and clouds without dramatically affecting their properties. In the centre of the galaxy, on the other hand, environmental conditions lead to larger, more massive clouds. While the galaxy interaction has little effect on cloud masses and sizes, it does promote the formation of counter-rotating clouds. We find that the identified clouds seem to be largely gravitationally unbound at first glance, but a closer analysis of the hierarchical structure of the molecular interstellar medium shows that there is a large range of virial parameters with a smooth transition from unbound to mostly bound for the densest structures. The common observation that clouds appear to be virialised entities may therefore be due to CO bright emission highlighting a specific level in this hierarchical binding sequence. The small fraction of gravitationally bound structures found suggests that low galactic star formation efficiencies may be set by the process of cloud formation and initial collapse.Comment: 22 pages, 26 figures, 2 tables. Properties of the clouds in the catalog are provided as a supplementary fil

Simulations of the star-forming molecular gas in an interacting M51-like galaxy : cloud population statistics

Funding: They also acknowledge funding from the European Research Council in the ERC Synergy Grant ‘ECOGAL – Understanding our Galactic ecosystem: From the disk of the Milky Way to the formation sites of stars and planets’ (project ID 855130). RJS gratefully acknowledges an STFC Ernest Rutherford fellowship (grant ST/N00485X/1).To investigate how molecular clouds react to different environmental conditions at a galactic scale, we present a catalogue of giant molecular clouds (GMCs) resolved down to masses of ∼10 M⊙ from a simulation of the entire disc of an interacting M51-like galaxy and a comparable isolated galaxy. Our model includes time-dependent gas chemistry, sink particles for star formation, and supernova feedback, meaning we are not reliant on star formation recipes based on threshold densities and can follow the physics of the cold molecular phase. We extract GMCs from the simulations and analyse their properties. In the disc of our simulated galaxies, spiral arms seem to act merely as snowplows, gathering gas, and clouds without dramatically affecting their properties. In the centre of the galaxy, on the other hand, environmental conditions lead to larger, more massive clouds. While the galaxy interaction has little effect on cloud masses and sizes, it does promote the formation of counter-rotating clouds. We find that the identified clouds seem to be largely gravitationally unbound at first glance, but a closer analysis of the hierarchical structure of the molecular interstellar medium shows that there is a large range of virial parameters with a smooth transition from unbound to mostly bound for the densest structures. The common observation that clouds appear to be virialized entities may therefore be due to CO bright emission highlighting a specific level in this hierarchical binding sequence. The small fraction of gravitationally bound structures found suggests that low galactic star formation efficiencies may be set by the process of cloud formation and initial collapse.Peer reviewe

Salt tectonics and controls on halokinetic-sequence development of an exposed deepwater diapir: The Bakio Diapir, Basque-Cantabrian Basin, Pyrenees

This work evaluates growth strata adjacent to the Bakio Diapir in the Basque Pyrenees, aiming to discuss the application of halokinetic-sequence concepts, mainly developed in shallow-water to subaerial environments, to deepwater depositional settings. This is one of the few exposed passive diapirs developed in deepwater environments, with both synkinematic carbonate and siliciclastic strata. Thus, considering that large hydrocarbon producing areas are located in salt provinces developed in deepwater environments, this study is of interest not only to researchers in salt tectonics, but also to industry geoscientists focusing on hydrocarbon exploration and production. We present a 3D analysis of this outstanding salt structure by integrating detailed geological cartography, high-resolution bathymetry, seismic, and well data. The resulting reconstruction enables us to trace the extent of the diapir offshore and decipher its evolution from its formation as a salt wall developed above the overlap of two basement-involved faults until its squeezing during the Pyrenean compression. But more significantly, it allows us to discern the roles played by bathymetry, subsidence, and sedimentation type in the configuration of halokinetic sequences developed in deepwater environments. Thus, our study shows that: 1) the geometry of halokinetic sequences is defined by the thickness of the roof edges, the dip of the salt-sediment interface in the limbs of the active drape fold, and the onlap angle of the synkinematic sediments over the salt; 2) the roof thickness is controlled not only by the ratio between salt-rise and regional sediment-accumulation rate, but also by the water depth of the diapir roof and the depositional environment that can promote vertical aggradation of a supra-diapir carbonate buildup; and 3) high surface slopes and consequent debrites are not exclusive to, and characteristic of, hook halokinetic sequences and tabular composite halokinetic sequences

Influence on preexisting salt diapirs during thrust wedge evolution and secondary welding: insights from analogue modeling

Salt lithologies are mechanically weaker than other sedimentary rocks. Salt horizons usually act as décollements and precursor salt bodies preferentially deform early during contraction, concentrate deformation, and impact the structural style and kinematics during mountain building. Focusing on shortened isolated-diapir provinces, our analog modeling program investigates the influence of two salt walls on folding and thrusting. High resolution topographic scans and particle image analysis show that the presence of precursor diapirs impacts the layer parallel shortening patterns and presumably the stress field at the onset of contraction. Shortening concentrates on diapirs, leading to roof arching, crestal extension and salt extrusion. This sequence of events occurs earlier on thinner salt- sediment sequences including diapirs having well-developed pedestals, particularly when proximal to the deformation front. Folds and thrusts nucleate at salt walls if they feature a well-developed pedestal. Further shortening results in secondary welding as evidenced by the collapse of uplifted roof domes, cessation of indentation and reverse faulting nucleated at the secondary welds. Meanwhile, and depending upon the processes occurring on the diapir closer to the backstop, the deformation of the distal salt wall is discontinuous. Our modeling results are compared with experimental works and natural examples from the Fars (Zagros Mountains)

sígame v3: Gas Fragmentation in Postprocessing of Cosmological Simulations for More Accurate Infrared Line Emission Modeling

We present an update to the framework called Simulator of Galaxy Millimeter/submillimeter Emission (SÍGAME). SÍGAME derives line emission in the far-infrared (FIR) for galaxies in particle-based cosmological hydrodynamics simulations by applying radiative transfer and physics recipes via a postprocessing step after completion of the simulation. In this version, a new technique is developed to model higher gas densities by parameterizing the probability distribution function (PDF) of the gas density in higher-resolution simulations run with the pseudoLagrangian, Voronoi mesh code AREPO. The parameterized PDFs are used as a look-up table, and reach higher densities than in previous work. SÍGAME v3 is tested on redshift z = 0 galaxies drawn from the SIMBA cosmological simulation for eight FIR emission lines tracing vastly different phases of the interstellar medium. This version of SÍGAME includes dust radiative transfer with SKIRT and high-resolution photoionization models with CLOUDY, the latter sampled according to the density PDF of the AREPO simulations to augment the densities in the cosmological simulation. The quartile distributions of the predicted line luminosities overlap with the observed range for nearby galaxies of similar star formation rate (SFR) for all but two emission lines: [O I]63 and CO(3–2), which are overestimated by median factors of 1.3 and 1.0 dex, respectively, compared to the observed line–SFR relation of mixed-type galaxies. We attribute the remaining disagreement with observations to the lack of precise attenuation of the interstellar light on sub-grid scales (200 pc) and differences in sample selection