Author Index     

Andrew L. Macumber  R. Timothy Patterson  Lisa A. Neville  Hendrik Falck 《Journal of Paleolimnology》2003,29(4):511-511

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Limiters in Third-Generation Wind Wave Models     

Hendrik Tolman 《Journal of Atmospheric & Ocean Science》2002,8(1):67-83

Third-generation ocean wave models include a so-called limiter in the integration of the source terms to guarantee numerical stability at economical numerical time steps. The original limiter has previously been associated with the sensitivity of model results to the numerical time step. More recent limiters appear to remove this sensitivity by eliminating the numerical convergence from the resulting integration scheme. This is contrary to rudimentary numerical principles as well as the underlying philosophy of third-generation wave models. The present study investigates the effects of limiters and large model time steps using time-limited wave growth test. It is shown that the conventional limiter results in stable model results even if the numerical time step violates the time scales of wave growth. Contrary to common belief, its impact is not necessarily limited to the equilibrium range of the spectrum, and the limiter systematically enhances growth rates in the intermediate stages of wave growth. Particularly initial growth errors increase significantly with increasing maximum discrete spectral frequency f max . Relaxation of the limiter is shown to reduce initial growth errors, but does so at the expense of notable errors in the spectral shape. In the present paper the limiter was relaxed by introducing a new asymmetric limiter that retains full convergence. Initial results obtained with this limiter are similar to those of the advocated nonconvergent limiters. Although this limiter still needs rigorous testing and further development, its initial results suggest that there is no justification for using nonconvergent limiters.  相似文献   

Sequence stratigraphic and genetic aspects of the Tournaisian "Liegender Alaunschiefer" and adjacent beds     

Hendrik Siegmund  Jörg Trappe  Wolfgang Oschmann 《International Journal of Earth Sciences》2002,91(5):934-949

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Echo sounding on suspended particulate matter in the elbe estuary     

Jobst Hülsemann  Hendrik Eden  Klaus Ricklefs 《Ocean Dynamics》1995,47(1):23-45

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Silver eel mortality during downstream migration in the River Meuse, from a population perspective     

Winter  Hendrik V.; Jansen  Henrice M.; Breukelaar  Andre W. 《ICES Journal of Marine Science》2007,64(7):1444-1449

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Migration history of North Sea houting (Coregonus oxyrinchus L.) caught in Lake IJsselmeer (The Netherlands) inferred from scale transects of 88Sr:44Ca ratios     

Jost Borcherding  Carola Pickhardt  Hendrik V. Winter  J. Sabine Becker 《Aquatic Sciences - Research Across Boundaries》2008,70(1):47-56

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Could alluvial knickpoint retreat rather than fire drive the loss of alluvial wet monsoon forest,tropical northern Australia?          下载免费PDF全文

Annegret Larsen  Jan‐Hendrik May  Patrick Moss  Jorg Hacker 《地球表面变化过程与地形》2016,41(11):1583-1594

Drainage rejuvenation through headward migration of alluvial knickpoints is common in ephemeral semi‐arid streams, but has not yet been described for tropical rivers. In the Australian monsoon tropics (AMT), wet monsoon forests have an important ecological function, and are present along many alluvial valleys and springs within a eucalypt‐savanna dominated landscape. Using a combination of LiDAR, remote sensing and field evidence, we observe the ongoing destruction of wet monsoon forest through hydro‐geomorphic feedbacks, along with the headward retreat of an alluvial knickpoint at Wangi Creek in Litchfield National Park, Northern Territory. Due to the highly transmissive shallow aquifer along the lower Wangi Creek, this knickpoint retreat leads to a downstream drop in in‐channel water level, which in turn drives a decrease in the local groundwater table. The lowered groundwater level causes the shallow anabranches and formerly water saturated peaty floodplain soil to desiccate, which results in a reduction of vegetation density. The resulting dry surface conditions allow annual to bi‐annual high frequency low‐intensity fires to affect the monsoon forest, while wet rainforest upstream of the knickpoint remains intact. In this paper, we argue that such hydro‐geomorphic feedbacks may cause the initial destabilization of the forest, which then provides the necessary conditions for the impact of fire. This scenario thus challenges the prevalent view that fire is a first‐order control on the spatial extent of wet monsoonal rainforest in the study area, and provides a new and testable hypothesis for further studies in the AMT. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

Sediment recycling and adjustment of deposition during deglacial drowning of a low-accumulation shelf (NW Iberia)     

Hendrik Lantzsch  Till J.J. HanebuthRüdiger Henrich 《Continental Shelf Research》2010

Based on a well-established stratigraphic framework and 47 AMS-¹⁴C dated sediment cores, the distribution of facies types on the NW Iberian margin is analysed in response to the last deglacial sea-level rise, thus providing a case study on the sedimentary evolution of a high-energy, low-accumulation shelf system.  相似文献   

Space time structures     

Hendrik Van Dam 《Celestial Mechanics and Dynamical Astronomy》1986,38(4):389-389

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Carbon in olivine single crystals analyzed by the ¹²C(d,p)¹³C method and by photoelectron spectroscopy     

Gert Oberheuser  Hendrik Kathrein  Guy Demortier  Horst Gonska  Friedemann Freund 《Geochimica et cosmochimica acta》1983,47(6):1117-1129

Carbon subsurface concentration profiles in olivine single crystals from San Carlos, Arizona, and the Sergebet Island. Red Sea, containing total carbon between 60–180 wt.-ppm, were analyzed by means of the ¹²C(d. p)¹³C nuclear reaction and by x-ray induced photoelectron spectroscopy (XPS) in combination with acid etching and with Ar⁺ ion sputtering respectively, between 200–930 K. The (d, p) analysis reveals equilibrium subsurface C profiles extending 1–2 μm or more into the bulk. Their steepness is a function of temperature. Typical mean C concentrations at 300 K in the resolvable layers, 0–0.6, 0.6–1.2, and 1.2–1.8 μm. are 1.8, and 0.6 wt.-%, corresponding to enrichment factors over the mean bulk C concentration of the order of 100, 40 and 30 respectively. In the topmost atomic layers analyzed by XPS the carbon is enriched by a factor of the order of 1000, decreasing with increasing temperature. The results suggest that the carbon is in a truly dissolved state and highly mobile, subject to a reversible subsurface segregation. Most probably local lattice strain associated with the solute C species provide the driving force for this diffusional process. The C diffusion coefficient was determined from the (d, p) data below 300 K: D= 10^?13 exp(?7.8/RT) [m²· sec^?1; KJ · mole^?1] and from XPS data between 450–925 K: D = 10^?14 exp(-6/RT) [m² · sec^?1; KJ · mole^?1] The estimated error of the preexponential factors is ± one order of magnitude, that of the activation energies ±3.5 and ±2 KJ mole^?1 respectively.  相似文献