The Impact of Dimensionality on Barotropic Processes during KWAJEX

Abstract In this study, the 2D and 3D cloud-resolving model simulations of the Tropical Rainfall Measuring Mission (TRMM) Kwajalein Experiment (KWAJEX) are compared to study the impact of dimensionality on barotropic processes during tropical convective development. Barotropic conversion of perturbation kinetic energy is associated with vertical transport of horizontal momentum under vertical shear of background horizontal winds. The similarities in both 2D and 3D model simulations show that 1) vertical wind shear is a necessary condition for barotropic conversion, but it does not control the barotropic conversion; 2) the evolution of barotropic conversion is related to that of the vertical transport of horizontal momentum; and 3) the tendency of vertical transport of horizontal momentum is mainly determined by the covariance between horizontal wind and the cloud hydrometeor component of buoyancy. The differences between the 2D and 3D model simulations reveal that 1) the barotropic conversion has shorter time scales and a larger contribution in the 2D model simulation than in the 3D model simulation and 2) kinetic energy is generally converted from the mean circulations to perturbation circulations in the 3D model simulation. In contrast, more kinetic energy is transferred from perturbation circulations to the mean circulations in the 2D model simulation. The same large-scale vertical velocity may account for the similarities, whereas the inclusion of meridional winds in the 3D model simulation may be responsible for the differences in barotropic conversion between the 2D and 3D model simulations.

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Estimation of Probable Maximum Precipitation (PMP) and Probable Maximum Flood (PMF) Using GSSHA Model (Case Study Area Upper Citarum Watershed)

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/893/1/012023 ◽

2021 ◽

Vol 893 (1) ◽

pp. 012023

Author(s):

Puji R A Sibuea ◽

Dewi R Agriamah ◽

Edi Riawan ◽

Rusmawan Suwarman ◽

Atika Lubis

Keyword(s):

Model Simulation ◽

Hydrologic Model ◽

Model Case ◽

Probable Maximum Precipitation ◽

Maximum Precipitation ◽

Hydrologic Analysis ◽

Probable Maximum Flood ◽

The Mean ◽

The Impact

Abstract Probable Maximum Flood (PMF) used in the design of hydrological structures reliabilities and safety which its value is obtained from the Probable Maximum Precipitation (PMP). The objectives of this study are to estimate PMP and PMF value in Upper Citarum Watershed and understand the impact from different PMP value to PMF value with two scenarios those are Scenario A and B. Scenario A will calculate the PMP value from each Global Satellite Mapping of Precipitation (GSMaP) rainfall data grid and Scenario B calculate the PMP value from the mean area rainfall. PMP value will be obtained by the statistical Hershfield method, and the PMF will be obtained by employed the PMP value as the input data in Gridded Surface Subsurface Hydrologic Analysis (GSSHA) hydrologic model. Model simulation results for PMF hydrographs from both scenarios show that spatial distribution of rainfall in the Upper Citarum watershed will affect the calculated discharge and whether Scenario A or B can be applied in the study area for PMP duration equal or higher than 72 hours. PMF peak discharge for Scenario A is averagely 13,12% larger than Scenario B.

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Regimes of Dry Convection above Wildfires: Sensitivity to Fire Line Details

Journal of the Atmospheric Sciences ◽

10.1175/2009jas3226.1 ◽

2010 ◽

Vol 67 (3) ◽

pp. 611-632 ◽

Cited By ~ 1

Author(s):

Michael T. Kiefer ◽

Matthew D. Parker ◽

Joseph J. Charney

Keyword(s):

Line Shape ◽

3D Model ◽

Three Dimensional ◽

Vertical Wind Shear ◽

Heating Rates ◽

3D Simulations ◽

Complex Phenomena ◽

2D And 3D ◽

The Impact ◽

Dry Convection

Abstract Fire lines are complex phenomena with a broad range of scales of cross-line dimension, undulations, and along-line variation in heating rates. While some earlier studies have examined parcel processes in two-dimensional simulations, the complexity of fire lines in nature motivates a study in which the impact of three-dimensional fire line details on parcel processes is examined systematically. This numerical modeling study aims to understand how fundamental processes identified in 2D simulations operate in 3D simulations where the fire line is neither straight nor uniform in intensity. The first step is to perform simulations in a 3D model, with no fire line undulations or inhomogeneity. In general, convective modes simulated in the 2D model are reproduced in the 3D model. In one particular case with strong vertical wind shear, new convection develops separate from the main line of convection as a result of local changes to parcel speed and heating. However, in general the processes in the 2D and 3D simulations are identical. The second step is to examine 3D experiments wherein fire line shape and along-line inhomogeneity are varied. Parcel heating, as well as convective mode, is shown to exhibit sensitivity to fire line shape and along-line inhomogeneity.

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Using Multi-Sensory and Multi-Dimensional Immersive Virtual Reality in Participatory Planning

Urban Science ◽

10.3390/urbansci4030034 ◽

2020 ◽

Vol 4 (3) ◽

pp. 34

Author(s):

Mahbubur Meenar ◽

Jennifer Kitson

Keyword(s):

Virtual Reality ◽

Focus Group ◽

Spatial Planning ◽

3D Model ◽

Emotional Responses ◽

Digital Technologies ◽

Participatory Planning ◽

Immersive Virtual Reality ◽

Model Simulations ◽

The Impact

In the last two decades, urban planners have embraced digital technologies to complement traditional public participation processes; research on the impact of smarter digital instruments, such as immersive virtual reality (IVR), however, is scant. We recruited 40 focus group participants to explore various formats of spatial planning scenario simulations in Glassboro, NJ, USA. Our study finds that the level of participation, memory recalls of scenarios, and emotional responses to design proposals are higher with multi-sensory and multi-dimensional IVR simulations than with standard presentations such as 2D videos of 3D model simulations, coupled with verbal presentations. We also discuss the limitations of IVR technology to assist urban planning practitioners in evaluating its potential in their own participatory planning efforts.

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Numerical modeling of seismically-induced slope displacements: a comparison between 2D and 3D finite difference models and Newmark-Displacements

10.5194/egusphere-egu2020-4186 ◽

2020 ◽

Author(s):

Gisela Domej ◽

Céline Bourdeau

Keyword(s):

Finite Difference ◽

Cross Section ◽

3D Model ◽

3D Models ◽

Southern Spain ◽

Longitudinal Cross Section ◽

Landslide Body ◽

Mesh Grid ◽

2D And 3D ◽

2D Model

The majority of numerical landslide models are designed in 2D. In particular, models based on finite difference methods (FDM) are time-consuming and &#8211; as a result &#8211; in most cases also cost-intensive. 3D models, therefore, increase the processing time significantly. Another contributing factor to long processing times in the context of modeling of seismically-induced displacements is the fact that mesh grid increments must be small due to the necessity of correct wave propagation through the material. The larger the frequency range of the applied seismic signal should be, the smaller has to be the mesh grid increment. 3D models are, however, considered as more realistic.In this work, we present a comprehensive study on numerical 2D and 3D models of the Diezma Landslide, Southern Spain. The Landslide is represented in its shape as it appeared at the time of the main rupture on 18th of March in four model layouts: (1) a simplified model in 3D that outlines the landslide body with planar triangular tiles, (2) a longitudinal cross section through this simplified 3D model representing the simplified 2D model, (3) a smooth model in 3D that envelops the landslide body according to the main topographic features, and (4) a longitudinal cross section through this smooth 3D model representing the smooth 2D model.On both the simplified and the smooth 2D models, a series of 11 seismic scenarios was applied as SV-waves assuming a source sufficiently far for vertical incidence at the model bottoms in order to produce horizontal shear inside the landslide body with respect to the underlying bedrock. All 11 signals are characterized by different frequency contents, Arias Intensities from 0.1 to 1 m/s, moment magnitudes from 5.0 to 7.0 and peak ground accelerations from 0.8 to 1.2 m/s&#178;, and therefore correspond to scenarios that represent the local seismicity in Southern Spain. Because of time-related limitations, only four of these signals were respectively applied to the simplified and smooth 3D model. Newmark-Displacements were calculated using all 11 signals with the classic Newmark-Method that approximates the landslide body in 2D by a rigid block on an inclined plane, and with Newmark&#8217;s Empirical Law as spatial information covering the landslide area across the slope in regular intervals.We present a systematic comparison of all models and obtained displacements, showing that the Newmark-Methods deliver very similar results to the maximum displacements obtained by FDM. Moreover, we discuss on a particular example that &#8211; although seeming more accurate in the layout &#8211; smooth models lead not necessarily to realistic results.

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The Impact of Milankovitch Solar Radiation Variations on Sea-Ice and Air Temperature in a Coupled Energy-Balance Climate-Sea-Ice Model

Annals of Glaciology ◽

10.3189/s0260305500008454 ◽

1990 ◽

Vol 14 ◽

pp. 144-147 ◽

Cited By ~ 1

Author(s):

Tamara Shapiro Ledley

Keyword(s):

Solar Radiation ◽

Sea Ice ◽

Air Temperature ◽

Energy Transport ◽

Model Simulation ◽

Surface Air Temperature ◽

Ice Thickness ◽

Sea Ice Thickness ◽

The Mean ◽

The Impact

The sensitivity of thermodynamically-varying sea-ice and surface air temperature to variations in solar radiation on the 104 to 105 time scales is examined in this study. Model simulation results show the mean annual sea-ice thickness is very sensitive to the magnitude of midsummer solar radiation. During periods of high midsummer solar radiation between 115 ka B.P. and the present the sea ice is thinner, producing larger summer time leads and longer periods of open ocean. This has an effect on the mean annual sea-ice thickness, but not on the mean annual air temperature. However, the changes in sea ice are accompanied by similar variations in the summer surface air temperature, which are the result of the variations in the solar radiation and meridional energy transport.

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The Impact of Milankovitch Solar Radiation Variations on Sea-Ice and Air Temperature in a Coupled Energy-Balance Climate-Sea-Ice Model

Annals of Glaciology ◽

10.1017/s0260305500008454 ◽

1990 ◽

Vol 14 ◽

pp. 144-147 ◽

Cited By ~ 5

Author(s):

Tamara Shapiro Ledley

Keyword(s):

Solar Radiation ◽

Sea Ice ◽

Air Temperature ◽

Energy Transport ◽

Model Simulation ◽

Surface Air Temperature ◽

Ice Thickness ◽

Sea Ice Thickness ◽

The Mean ◽

The Impact

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The Monash Simple Climate Model Experiments (MSCM-DB v1.0): An interactive database of mean climate, climate change and scenario simulations

10.5194/gmd-2018-143 ◽

2018 ◽

Author(s):

Dietmar Dommenget ◽

Kerry Nice ◽

Tobias Bayr ◽

Dieter Kasang ◽

Christian Stassen ◽

...

Keyword(s):

General Circulation ◽

Climate Model ◽

Model Simulation ◽

Co2 Concentration ◽

General Circulation Models ◽

Simple Climate Model ◽

Model Simulations ◽

Sensitivity Experiments ◽

The Mean ◽

Mean Climate

Abstract. This study introduces the Monash Simple Climate Model (MSCM) experiment database. The model simulations are based on the Globally Resolved Energy Balance (GREB) model. They provide a basis to study three different aspects of climate model simulations: (1) understanding the processes that control the mean climate, (2) the response of the climate to a doubling of the CO2 concentration, and (3) scenarios of external CO2 concentration and solar radiation forcings. A series of sensitivity experiments in which elements of the climate system are turned off in various combinations are used to address (1) and (2). This database currently provides more than 1,300 experiments and has an online web interface for fast analysis of the experiments and for open access to the data. We briefly outline the design of all experiments, give a discussion of some results, and put the findings into the context of previously published results from similar experiments. We briefly discuss the quality and limitations of the MSCM experiments and also give an outlook on possible further developments. The GREB model simulation of the mean climate processes is quite realistic, but does have uncertainties in the order of 20–30 %. The GREB model without flux corrections has a root mean square error in mean state of about 10 °C, which is larger than those of general circulation models (2 °C). However, the MSCM experiments show good agreement to previously published studies. Although GREB is a very simple model, it delivers good first-order estimates, is very fast, highly accessible, and can be used to quickly try many different sensitivity experiments or scenarios.

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Assessment of the local mechano-electrochemical effect on pipeline defects by 2D and 3D finite element models

CORROSION ◽

10.5006/3774 ◽

2021 ◽

Author(s):

Zhuwu Zhang ◽

Jiuhong Zhang ◽

Jinchang Wang ◽

Y. Frank Cheng

Keyword(s):

Finite Element ◽

3D Model ◽

Local Stress ◽

Anodic Current Density ◽

Defect Center ◽

Zone Length ◽

3D Finite Element ◽

2D And 3D ◽

2D Model ◽

Anodic Zone

Local corrosion at a defect on a pipeline was assessed using both 2-dimensional (2D) and 3D finite element (FE) models under mechano-electrochemical (M-E) interaction. While the M-E interaction increases corrosion activity at the defect, the assessment of M-E interaction would have different results using 2D and 3D models. Compared with the 3D model, the 2D model produces a greater local stress, a higher local plastic strain, a more negative corrosion potential and a higher anodic current density at the defect, and thus, a lower threshold internal pressure causing local yielding. The 3D model is more conservative for corrosion rate prediction of corroded pipelines. A new concept, rAZ (the ratio of the anodic zone length to defect length in the 2D model, or the ratio of the anodic zone area to the defect area in the 3D model), is proposed to define growth mode of the corrosion defect. There is a smaller rAZ produced in 2D model. At specific internal pressures, the 2D model predicts an ellipsoidal defect center area experiencing accelerated corrosion and potentially resulting in pipeline leaking.

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Slope Stability Comparatively Analyzed with 2D and 3D FEM

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.220-223.2908 ◽

2012 ◽

Vol 220-223 ◽

pp. 2908-2911

Author(s):

Jie Qun Liu ◽

Jin Long Liu

Keyword(s):

Slope Stability ◽

Safety Factor ◽

3D Model ◽

Model Analysis ◽

Stability Factor ◽

Surface Load ◽

3D Fem ◽

The Stability ◽

2D And 3D ◽

2D Model

A typical slope has been comparatively analyzed with 2D and 3D FEM, it is showed that the length of surface load at top surface of slope shorted, the stability factor of slope of 3D model increased, which is far more than that of 2D model. In a certain degree, the safety factor got by 3D model is bigger than that of 2D model, so the safety factor of slope is underestimated by 2D model analysis sometimes.

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Constraints and biases in a tropospheric two-box model of OH

10.5194/acp-2018-798 ◽

2018 ◽

Cited By ~ 1

Author(s):

Stijn Naus ◽

Stephen A. Montzka ◽

Sudhanshu Pandey ◽

Sourish Basu ◽

Ed J. Dlugokencky ◽

...

Keyword(s):

Hydroxyl Radical ◽

3D Model ◽

Model Simulation ◽

Box Model ◽

Surface Measurement ◽

Model Parameters ◽

Ch4 Emissions ◽

Wide Range ◽

The Impact ◽

Bias Corrections

Abstract. The hydroxyl radical (OH) is the main atmospheric oxidant and the primary sink of the greenhouse gas CH4. In two recent studies, constraints on the hydroxyl radical (OH) were derived using a tropospheric two-box model of methyl chloroform (MCF) and CH4. When OH variations as derived in this set-up were propagated to the CH4 budget, the constraints on OH from MCF still allowed for a wide range of CH4 emission scenarios. This is important, because global CH4 emissions are generally considered best constrained by the global lifetime of CH4, which is determined mainly by OH. Here, we investigate how the use of a tropospheric two-box model in these studies can have affected derived constraints on OH, due to the simplifying assumptions inherent to a two-box model. First, instead of prescribing fixed model parameters for interhemispheric transport, chemical loss rates and loss to the stratosphere, we derive species- and time-dependent quantities from a full 3D transport model simulation. We find significant deviations between the magnitude and time-dependence of the parameters we derive, and the assumptions commonly reported and adopted in literature. Moreover, using output from the 3D model simulations, we investigated differences between the burden seen by the surface measurement network of the National Oceanic and Atmospheric Administration and the true tropospheric burden. Next, we accounted for these biases in a two-box model inversion of MCF and CH4, to investigate the impact of the biases on OH constraints. We find that the sensitivity of interannual OH anomalies to the biases is modest (1–2 %), relative to the significant uncertainties on derived OH (5–8 %). However, in an inversion where we implemented all four bias corrections simultaneously, we did find a shift to a positive OH trend over the 1994–2015 period. Moreover, the magnitude of derived global mean OH and by extent that of global CH4 emissions are affected much more strongly by the bias corrections than their anomalies (∼ 10 %). In this way, we identified and quantified direct limitations in the two-box model approach that can possibly be corrected for when a full 3D simulation is used to inform the two-box model. This derivation is, however, an extensive and species-dependent exercise. Therefore, a good alternative would be to move the inversion problem of OH to a 3D model completely. It is crucial to account for the limitations of two-box models in future attempts to constrain the atmospheric oxidative capacity, especially because though MCF and CH4 behave similarly in large parts of our analysis, it is not obvious that this should be the case for alternative tracers that potentially constrain OH, other than MCF.

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