Coastal flooding in Scotland: towards national-level hazard assessment     

Tom Ball  Anton Edwards  Alan Werritty 《Natural Hazards》2014,70(2):1133-1152

This study investigated contributory factors to flood hazard around Scotland. There is a need to develop preliminary assessments of areas potentially vulnerable to flooding for compliance with the European Union Directive on the Assessment and Management of Flood Risks (2007/60/EC). Historical accounts of coastal flood events in Scotland, notably in a storm in January 2005, had shown that estimates of risk based on still water levels required further information to identify sites at which waves and surges could combine. Additionally, it was important to add the effect of future sea-level rise and other drivers from published sources. Analysis of multiple years’ tidal data at seven sites, including estuaries, compared recorded water levels at high-return periods to those derived from a spatially interpolated numerical model contained within a publicly available flood risk map. For gauges with the longest records, increases were seen over time that reflected rises in mean sea level. Exposure to wave energy was computed from prevailing wind strength and direction at 36 stations, related to wave fetch and incident wind direction. Although the highest wave exposure was at open coast locations exposed to the long Atlantic fetch, GIS analysis of coastal rasters identified other areas in or close to estuaries that also had high exposure. Projected sea-level change, when added to the surge and wave analyses, gives a spatially extensive structured variable flood risk assessment for future coastal flood hazard to complement the public flood risk map. Such tools can help fulfil the requirements of the EC Directive and may be a useful approach in other regions with high spatial variability in coastal flood risk related to exposure to waves and wind.  相似文献   

Ice caps existed throughout the Lateglacial Interstadial in northern Scotland     

Tom Bradwell  Derek Fabel  Martyn Stoker  Hannah Mathers  Lanny McHargue  John Howe 《第四纪科学杂志》2008,23(5):401-407

We constrain, in detail, fluctuations of two former ice caps in NW Scotland with multibeam seabed surveys, geomorphological mapping and cosmogenic ¹⁰Be isotope analyses. We map a continuous sequence of 40 recessional moraines stretching from ～10 km offshore to the Wester Ross mountains. Surface‐exposure ages from boulders on moraine ridges in Assynt and the Summer Isles region show that substantial, dynamic, ice caps existed in NW Scotland between 13 and 14 ka BP. We interpret this as strong evidence that large active glaciers probably survived throughout the Lateglacial Interstadial, and that during the Older Dryas period (ca. 14 ka BP) ice caps in NW Scotland were thicker and considerably more extensive than in the subsequent Younger Dryas Stadial. By inference, we suggest that Lateglacial ice‐cap oscillations in Scotland reflect the complex interplay between changing temperature and precipitation regimes during this climatically unstable period (ca. 15–11 ka BP). © Natural Environment Research Council (NERC) copyright 2008. Reproduced with the permission of NERC. Published by John Wiley & Sons, Ltd.  相似文献   

Ion winds in Saturn's southern auroral/polar region     

Tom S Stallard  Steve Miller  Laurence M Trafton  Robert D Joseph 《Icarus》2004,167(1):204-211

We present profiles of the line-of-sight (l.o.s.) ionospheric wind velocities in the southern auroral/polar region of Saturn. Our velocities are derived from the measurement of Doppler shifting of the H₃⁺ν₂Q(1,0⁻) line at 3.953 microns. The data for this study were obtained using the facility high-resolution spectrometer CSHELL on the NASA Infrared Telescope Facility (IRTF) on Mauna Kea, Hawaii, during the night of February 6, 2003 (UT). The l.o.s. velocity profiles finally derived are consistent with an extended region of the upper atmosphere sub-corotating with the planet: the ion velocities in the inertial reference are only 1/3 of those expected for full planetary corotation. We discuss the results in the light of recent proposals for the kronian magnetosphere, and suggest that, in this region, Saturn's ion winds may be under solar wind control.  相似文献   

Star formation and feedback in smoothed particle hydrodynamic simulations – I. Isolated galaxies     

Greg Stinson  Anil Seth  Neal Katz  James Wadsley  Fabio Governato  Tom Quinn 《Monthly notices of the Royal Astronomical Society》2006,373(3):1074-1090

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Intermediate mass black holes in accreting binaries: formation, evolution and observational appearance     

Simon F. Portegies Zwart  Jasinta Dewi  Tom Maccarone 《Monthly notices of the Royal Astronomical Society》2004,355(2):413-423

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Photometric study of new southern SU UMa-type dwarf novae and candidates – III. NSV 10934, MM Sco, AB Nor and CAL 86     

Taichi Kato  Peter Nelson  Chris Stockdale  Berto Monard  Tom Richards  Rod Stubbings  Hitoshi Yamaoka  Bernard Heathcote  Roland Santallo 《Monthly notices of the Royal Astronomical Society》2004,347(3):861-872

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The 6dF Galaxy Survey: samples, observational techniques and the first data release     

D. Heath Jones  Will Saunders  Matthew Colless  Mike A. Read  Quentin A. Parker  Fred G. Watson  Lachlan A. Campbell  Daniel Burkey  Thomas Mauch  Lesa Moore  Malcolm Hartley  Paul Cass  Dionne James  Ken Russell  Kristin Fiegert  John Dawe  John Huchra  Tom Jarrett  Ofer Lahav  John Lucey  Gary A. Mamon  Dominique Proust  Elaine M. Sadler  Ken-ichi Wakamatsu 《Monthly notices of the Royal Astronomical Society》2004,355(3):747-763

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The contribution of faint blue galaxies to the submillimetre counts and background     

Geoff S. Busswell  Tom Shanks 《Monthly notices of the Royal Astronomical Society》2001,323(1):67-74

Observations in the submillimetre (submm) waveband have recently revealed a new population of luminous sources. These are proposed to lie at high redshift and to be optically faint because of their high intrinsic dust obscuration. The presence of dust has been previously invoked in optical galaxy count models which use the Bruzual & Charlot evolution models with an exponential τ =9 Gyr star formation rate (SFR) for spirals, and these fit the count data well from U to K . We now show that by using either a 1/ λ or Calzetti absorption law for the dust and re-distributing the evolved spiral galaxy ultraviolet (UV) radiation into the far-infrared (FIR), these models can account for all of the 'faint' ( 1 mJy) 850-μm galaxy counts, but fail to fit 'bright' ( 2 mJy) sources, indicating that another explanation for the submm counts may apply at brighter fluxes, e.g., quasi-stellar objects (QSOs) or ultraluminous infrared galaxies (ULIRGs). We find that the main contribution to the faint, submm number counts is in the redshift range 0.5< z <3, peaking at z ≈1.8. The above model, using either dust law, can also explain a significant proportion of the extragalactic background at 850 μm, as well as producing a reasonable fit to the bright 60-μm IRAS counts.  相似文献   

Probing the intergalactic medium with the Lyα forest along multiple lines of sight to distant QSOs     

M. Viel  S. Matarrese  H.J. Mo  M.G. Haehnelt  Tom Theuns 《Monthly notices of the Royal Astronomical Society》2002,329(4):848-862

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Cosmic reionization by stellar sources: population III stars     

Aaron Sokasian  Naoki Yoshida  Tom Abel  Lars Hernquist  Volker Springel 《Monthly notices of the Royal Astronomical Society》2004,350(1):47-65

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