The effect of changing spatial resolution in global dynamic wave models

Abstract A new procedure is introduced to downscale low-spatial-resolution inundation extents from Global Inundation Extent from Multi-Satellites (GIEMS) to a 3-arc-s (90 m) dataset (known as GIEMS-D3). The methodology is based on topography and hydrography information from the HydroSHEDS database. A new floodability index is introduced and an innovative smoothing procedure is developed to ensure a smooth transition, in the high-resolution maps, between the low-resolution boxes from GIEMS. Topography information is pertinent for natural hydrology environments controlled by elevation but is more limited in human-modified basins. However, the proposed downscaling approach is compatible with forthcoming fusion of other, more pertinent satellite information in these difficult regions. The resulting GIEMS-D3 database is the only high-spatial-resolution inundation database available globally at a monthly time scale over the 1993–2007 period. GIEMS-D3 is assessed by analyzing its spatial and temporal variability and evaluated by comparisons to other independent satellite observations from visible (Google Earth and Landsat), infrared (MODIS), and active microwave (synthetic aperture radar).

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Applicability of Kinematic, Noninertia, and Quasi-Steady Dynamic Wave Models to Unsteady Flow Routing

Journal of Hydraulic Engineering ◽

10.1061/(asce)0733-9429(2003)129:8(613) ◽

2003 ◽

Vol 129 (8) ◽

pp. 613-627 ◽

Cited By ~ 54

Author(s):

Christina W. Tsai

Keyword(s):

Unsteady Flow ◽

Flow Routing ◽

Wave Models ◽

Unsteady Flow Routing ◽

Dynamic Wave

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Nonlinear dynamic wave models of gas-liquid flows in technical systems

Automation Telemechanization and Communication in Oil Industry ◽

10.30713/0132-2222-2018-8-42-47 ◽

2018 ◽

pp. 42-47

Author(s):

R.A. Gasumov ◽

◽

V.A. Tolpaev ◽

K.S. Akhmedov ◽

A.M. Kravtsov ◽

...

Keyword(s):

Nonlinear Dynamic ◽

Technical Systems ◽

Wave Models ◽

Liquid Flows ◽

Dynamic Wave

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Sensitivity of Offshore Tropical Cyclone Wave Simulations to Spatial Resolution in Wave Models

Journal of Marine Science and Engineering ◽

10.3390/jmse6040116 ◽

2018 ◽

Vol 6 (4) ◽

pp. 116 ◽

Cited By ~ 2

Author(s):

Xuanyu Chen ◽

Isaac Ginis ◽

Tetsu Hara

Keyword(s):

Tropical Cyclone ◽

Spatial Resolution ◽

Fast Moving ◽

Wind Field ◽

Spatial Smoothing ◽

Wavewatch Iii ◽

The Mean ◽

Wave Models ◽

Storm Characteristics ◽

Coarse Grids

This study investigated and quantified the sensitivity of tropical cyclone (TC) wave simulations in the open ocean to different spatial resolutions ( 1 / 3 ∘ , 1 / 6 ∘ , 1 / 12 ∘ and 1 / 24 ∘ ) using two wave models, WAVEWATCH III (WW3) and Simulating WAves Nearshore (SWAN). Six idealized TCs of different radii of maximum winds (25 km and 50 km), and of different translation speeds (3 m/s, 6 m/s and 9 m/s) were prescribed to force these two wave models. Results from both models show that the coarsest resolution ( 1 / 3 ∘ ) introduces significant errors in both the significant wave height (SWH) and the mean wavelength. Moreover, results reveal that sensitivity to spatial resolution strongly depends on storm characteristics. Waves simulated under the small (25 km) and fast moving (9 m/s) TC show the largest sensitivity to the coarse spatial resolutions. With the 1 / 3 ∘ resolution, maximum SWH can be underestimated by as much as 6% in WW3 and 16% in SWAN compared to those with the 1 / 24 ∘ resolution. These findings from the idealized TC simulations are further confirmed by wave simulations under a historical storm. Our analysis also demonstrates that spatial smoothing of the input wind field with coarse grids is not the only reason for the errors in wave simulations.

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Applicability of Kinematic, Diffusion, and Quasi-Steady Dynamic Wave Models to Shallow Mud Flows

Journal of Hydrologic Engineering ◽

10.1061/(asce)he.1943-5584.0000881 ◽

2014 ◽

Vol 19 (5) ◽

pp. 956-965 ◽

Cited By ~ 13

Author(s):

Cristiana Di Cristo ◽

Michele Iervolino ◽

Andrea Vacca

Keyword(s):

Wave Models ◽

Dynamic Wave

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Evaluation of the Simplified Dynamic Wave, Diffusion Wave and the Full Dynamic Wave Flood Routing Models

Earth Science Research ◽

10.5539/esr.v7n2p14 ◽

2018 ◽

Vol 7 (2) ◽

pp. 14 ◽

Cited By ~ 4

Author(s):

John Perdikaris ◽

Bahram Gharabaghi ◽

Ramesh Rudra

Keyword(s):

Wave Model ◽

Ease Of Use ◽

Flood Routing ◽

Diffusion Wave ◽

Event Simulation ◽

Wave Diffusion ◽

Wave Models ◽

Accuracy Of Prediction ◽

Routing Models ◽

Dynamic Wave

The accuracy of prediction and ease of use of the three popular flood routing models; simplified dynamic Wave, diffusion wave, and full dynamic wave were evaluated. The models were evaluated along a reach of the Credit River Watershed, in Southern Ontario, Canada. The simplified dynamic wave model showed better accuracy and easier formulation when compared against the diffusion wave and the full dynamic wave models. Indicating that the simplified dynamic wave model can be applied to reaches where the diffusion wave and the full dynamic wave models may not be applicable. The principle novel contributions of the paper are (a) the extension of the flood routing formulations by Keskin and Agiralioglu, (b) the use of a prismatic channel and floodplain with varying top-widths, (c) the validation of the methodology through the application of an event simulation to an actual river reach, and (d) comparison of the modeling results to those obtained using the full dynamic wave model and the diffusion wave models.

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Spatial resolution of X-ray microanalysis in thin foils

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109860 ◽

1978 ◽

Vol 36 (1) ◽

pp. 544-545

Author(s):

R. Hutchings ◽

I.P. Jones ◽

M.H. Loretto ◽

R.E. Smallman

Keyword(s):

Spatial Resolution ◽

Electron Probe ◽

Beam Divergence ◽

Inelastic Interaction ◽

Specimen Thickness ◽

High Current ◽

Beam Spreading ◽

X Ray ◽

Thin Foils ◽

Complex Calculation

There is increasing interest in X-ray microanalysis of thin specimens and the present paper attempts to define some of the factors which govern the spatial resolution of this type of microanalysis. One of these factors is the spreading of the electron probe as it is transmitted through the specimen. There will always be some beam-spreading with small electron probes, because of the inevitable beam divergence associated with small, high current probes; a lower limit to the spatial resolution is thus 2αst where 2αs is the beam divergence and t the specimen thickness.In addition there will of course be beam spreading caused by elastic and inelastic interaction between the electron beam and the specimen. The angle through which electrons are scattered by the various scattering processes can vary from zero to 180° and it is clearly a very complex calculation to determine the effective size of the beam as it propagates through the specimen.

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Precipitation in silicon: Microanalysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100104431 ◽

1988 ◽

Vol 46 ◽

pp. 474-475

Author(s):

R.W. Carpenter

Keyword(s):

Transition Metals ◽

Spatial Resolution ◽

Thin Foil ◽

Precipitation Reaction ◽

High Current ◽

Reaction Products ◽

Carbon And Nitrogen ◽

Dielectric Layers ◽

Precipitation Processes ◽

Areas Of Interest

Interest in precipitation processes in silicon appears to be centered on transition metals (for intrinsic and extrinsic gettering), and oxygen and carbon in thermally aged materials, and on oxygen, carbon, and nitrogen in ion implanted materials to form buried dielectric layers. A steadily increasing number of applications of microanalysis to these problems are appearing. but still far less than the number of imaging/diffraction investigations. Microanalysis applications appear to be paced by instrumentation development. The precipitation reaction products are small and the presence of carbon is often an important consideration. Small high current probes are important and cryogenic specimen holders are required for consistent suppression of contamination buildup on specimen areas of interest. Focussed probes useful for microanalysis should be in the range of 0.1 to 1nA, and estimates of spatial resolution to be expected for thin foil specimens can be made from the curves shown in Fig. 1.

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High spatial resolution x-ray microanalysis of interfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100137793 ◽

1995 ◽

Vol 53 ◽

pp. 284-285

Author(s):

J. R. Michael

Keyword(s):

Spatial Resolution ◽

Electron Probe ◽

Solid Angle ◽

Collection Efficiency ◽

Spatial Scales ◽

Energy Dispersive Spectrometer ◽

X Rays ◽

X Ray ◽

Probe Size ◽

Brightness Field

X-ray microanalysis in the analytical electron microscope (AEM) refers to a technique by which chemical composition can be determined on spatial scales of less than 10 nm. There are many factors that influence the quality of x-ray microanalysis. The minimum probe size with sufficient current for microanalysis that can be generated determines the ultimate spatial resolution of each individual microanalysis. However, it is also necessary to collect efficiently the x-rays generated. Modern high brightness field emission gun equipped AEMs can now generate probes that are less than 1 nm in diameter with high probe currents. Improving the x-ray collection solid angle of the solid state energy dispersive spectrometer (EDS) results in more efficient collection of x-ray generated by the interaction of the electron probe with the specimen, thus reducing the minimum detectability limit. The combination of decreased interaction volume due to smaller electron probe size and the increased collection efficiency due to larger solid angle of x-ray collection should enhance our ability to study interfacial segregation.

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Scanning x-ray fluorescence microscopy and principal component analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100133394 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1752-1753

Author(s):

Brian Cross

Keyword(s):

Principal Component Analysis ◽

Fluorescence Microscopy ◽

Spatial Resolution ◽

High Speed ◽

Image Acquisition ◽

Principal Component ◽

Fluorescence Microscope ◽

Acquisition Rate ◽

X Ray ◽

Speed Up

A relatively new entry, in the field of microscopy, is the Scanning X-Ray Fluorescence Microscope (SXRFM). Using this type of instrument (e.g. Kevex Omicron X-ray Microprobe), one can obtain multiple elemental x-ray images, from the analysis of materials which show heterogeneity. The SXRFM obtains images by collimating an x-ray beam (e.g. 100 μm diameter), and then scanning the sample with a high-speed x-y stage. To speed up the image acquisition, data is acquired "on-the-fly" by slew-scanning the stage along the x-axis, like a TV or SEM scan. To reduce the overhead from "fly-back," the images can be acquired by bi-directional scanning of the x-axis. This results in very little overhead with the re-positioning of the sample stage. The image acquisition rate is dominated by the x-ray acquisition rate. Therefore, the total x-ray image acquisition rate, using the SXRFM, is very comparable to an SEM. Although the x-ray spatial resolution of the SXRFM is worse than an SEM (say 100 vs. 2 μm), there are several other advantages.

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