Questions tagged [numerical-modelling]
The numerical-modelling tag has no usage guidance.
71
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Bias correction of CMIP6 projections
Is it always mandatory to perform a bias correction when working with CMIP6 climate projections?
I am working with multiple climate projections from CMPI6 and I'm not sure if this step is necessary, ...
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2
votes
1
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Estimate EPW AMY parameters from HRRR Analysis
I am working to create Energy Plus Weather (EPW) Actual Meteorological Year (AMY) files from NOAA HRRR Model analysis. The provided links detail the 35 parameters required for the AMY model and ...
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13
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Shallow water model for year-round watershed runoff
I have an (maybe not so clever) idea to apply the shallow water model for computing the year-round watershed runoff of a catchment. It means using of real topography with variable slopes and roughness,...
4
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1
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Estimating atmospheric vertical motion from 3D fields in WRF output
I have WRF data on isobaric levels that unfortunately does not contain a z-wind or omega field within the output, and I would like to produce some estimate as to the magnitude of synoptic-scale ...
2
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1
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Understanding Graphs for Velocity and Temperature Solutions for Parallel Sided Slab on Slope Problem
I'm trying to recreate the graphs in Figure 6.2 from this source (page 88). They get these plots by using the following solutions for velocity and temperature (both obtained from solving the basic ...
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Query on the 'namelist.input' file for running WRF-Chem to study aerosol-cloud-climate interaction
I have a small inquiry about the setup of some variables in 'namelist.input' file for running WRF-Chem to study aerosol-cloud-climate interaction. After going through various research papers on ...
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23
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Conservation of mass in Integrated surface water and groundwater models
One of the fundamental principles in fluid mechanics is the conservation of mass - how is this treated in integrated surface water | groundwater models such as MIKE models, say between two river cross-...
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What is the benefit of Priessman Slots in Numerical modeling?
There is no descriptive content on the interneton what Priessman slots are and how they can be used in numerical modeling. What is the benefit of that especially in hydraulic modeling?
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MIKE SHE Lateral inflow outputs and the differences between them
There are four 'Lateral inflow' related variables coming out from the .res1d file
Lateral inflow SHE overland
Lateral inflow SHE saturated zone
Lateral inflow SHE overland drain
Lateral inflow SHE ...
1
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1
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divergence of static stability identical parameters
All,
The static stability of the atmosphere is defined as:
$\sigma =-\dfrac{T}{\theta} \dfrac{d\theta}{dp}= \dfrac{dT}{dp}-\dfrac{R}{c_p} \dfrac{T}{p}$
where:
$T$ is temperature,
$P$ is pressure,
$R$ ...
- 111
2
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0
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44
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US vs EU weather systems commercialization and precision? [closed]
The US and EU have very different government funding systems for weather and space equipment, perhaps as different as the road systems. The US has a higher performing health system on average at a ...
- 1,339
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Are there any online earth science formula/equation libraries?
I'm looking for a formula library like fxSolver but specifically for Earth science formulas. I could rummage through scientific papers like a nerd racoon, but first I want to make sure there isn't a ...
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1
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55
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Can we know if a numerical model will converge or not according to the boundary conditions?
Consider a square 2D domain and a steady-state simulation. According to the geology of the domain, the North, South, West and East limits must be conditions of zero flow (Neumann). The aquifer ...
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4
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How are boundary conditions considered in PDEs?
I'm new to numerical modeling and trying to figure out how things work inside business codes.
Consider a 1D domain divided into small cells of width dx and at the East and West a Neumann conditions ...
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2
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How do academics/institutions run large climate simulations given the computing challenges?
I have been brushing up on numerical methods for PDEs lately, and climate models provide such a rich set of models and ideas to practice with. However, I was a little confused about how academics can ...
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Why are all the variables ( DRY_DEP_FLUX and WET_DEP_FLUX) zero in a wrf model output in all the time steps
I am working on WRF_GHG, I would like to calculate dry and wet deposition in the dry and wet seasons for CO2 and CH4 gases. However, when I check the wrf output, I see that all the variables (...
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Calculating Love numbers (tidal deformation) for non-homogeneous planets
I have a question about planetology. I'm not sure if it belongs here, but the astronomy stack exchange seemed a bit odd, too.
I would like to enhance my understanding of Love numbers. Love numbers ...
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ESMF installation error "error: no match for ‘operator==’ "
I need to install ESMF-5.2.0rp3 version. I have downloaded it from https://github.com/esmf-org/esmf/releases/tag/ESMF_5_2_0rp3. Also I installed the following prerequisites: Fortran95, GCC & C++ 7....
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131
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wrf_chemi file with 30 time steps
I creat wrfchemi file for my wrf-chem, my wrfchemi file has 30 time step,
frames_per_auxinput5 = 30, 30,
auxinput5_inname = "wrfchemi_d",
auxinput5_interval_m = 60, 60,
...
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Is there a modelling of Wave Rock (Hyden Rock) formation?
I'm interested in the visualization of the formation process of "strange" objects like Wave Rock (flared slope). I've found articles describing hypotheses of the rock formation but I cannot ...
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How to install ESMF and ESMFPy in Ubuntu using gfortran, gcc, python?
I am trying to regrid some of my latitude-longitude grid files to tripolar ocean grid and found that ESMF can be useful. However, I am finding it hard to install the same.
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How to de-stagger (or unstagger) WRF wind fields?
I am trying to calculate wind speed from the U and V wind components of a Weather Research and Forecasting (WRF) simulation. However, I came to realize that some ...
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How to convert the units of specific cloud liquid water from ERA5 (kg/kg) to kg/m2?
I am trying to initialize my model with the cloud liquid water data from ERA5. My model IITM-ESM which evolved from CFSv2 takes in the cloud liquid water information in $\small\mathsf{kg/m^2}$. ...
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Model relating reservoir releases with downstream temperature
Are there any statistical/numerical models developed relating release from reservoirs with the downstream river temperatures? I know of complicated hydrodynamic models such as CE-QUAL-W2 etc. but I am ...
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Discrete distribution of daily rainfall [closed]
How can I estimate the rainfall rate every ten minutes during a day having the total amount of rainfall during that day ?
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1
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557
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How to determine the orientation of coastline from NetCDF file
I have a NetCDF file (gridded data) with a landsea mask. I would like to determine, for the coastal grid-cells, what the orientation of the coastline is. I need to do this in order to calculate the ...
- 607
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3
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Temperature Advection using finite differences with gridded data
Advection of a scalar quantity, such as temperature (T), by the horizontal wind, is defined as follows:
$-\textbf{U}\cdot\nabla T$
where $\textbf{U}$ is the horizontal wind vector, $\textbf{U}=(u,v)$...
- 607
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How to control output precision when running WRF?
I am very new in this area and wondering if anyone can answer my following questions:
I am running WRF (4.0.3, ideal) to study rounding and truncation. I use the NCL (6.5.0) print command to access ...
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271
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python generate 3d unstructured grid
I would like to create a 3d unstructured grid based on data points with xyz and property. Can Python do this and what tools?
My question is quite generic but i can provide more details: the data has ...
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Statistical dependence of mean annual soil evaporation and mean annual precipitation globally
I am studying a simple dynamical system that represents a plant and water system, similar to Klausmeier. In Klausmeier model the mean annual precipitation and the soil evaporation are introduced as ...
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Difference between model parameter and observable parameter
In Inverse problem theory, what is meant by "results of the measurements of observable parameter"?
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106
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WRF: minimal list of variables required by coupling a land surface model to the whole system
We are trying to couple our land surface model into WRF. As a first step, we'd like to know what is the minimal list of variables required by such coupling?
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Simple and realistic data for glacier modeling
I'm programming the nonlinear Stokes problem (with a finite element method),
$$\operatorname{div}(\mu(u)\nabla u+pI)=f$$
where $\mu(u)$ is the Glen's power flow law (typical for glaciers). I want to ...
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Calculate the number of model grid cells covering a specific country
What is the best method of calculating the number of model grid cells (e.g. of climate models) covering a specific country? For example, if I wanted to know how many 2 degree grid cells are in the ...
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How do spectral methods work in the context of numerical weather prediction models?
I am broadly familiar with the concept of numerical weather prediction models using various finite methods to solve the primitive equations used in these models, but how do spectral methods work, ...
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Why RBF is gridless and kriging is not?
I read about it somewhere in a paper. Why is kriging not gridless if I can krig points in space? Whats is the big difference from RBF?
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542
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correct way to calculate transport through a section in an ocean numerical model
Suppose that I want to calculate the transport across a certain transect (green line) from the outputs of an ocean numerical model. The model has the $u$ values at the center of the grids (crosses) ...
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Reasons for choosing LES in stead of RANS models?
In oceanography, is there any particular reason why choosing large eddy simulations in stead of RANS (regardless of the type of flow)? In both cases, 2d simulations would be used (shallow water model)....
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What is the equivalent of CFL criterion when using spectral models?
I would like to know what the equivalent of the CFL criterion is for atmospheric models based of spectral grids. In other words, how do you find the necessary horizontal resolution in meters for ...
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Visually Realistic Supercell Modeling
Are there any published descriptions of simple equations governing the formation, evolution, and decay of severe storms? Specifically, I am interested in equations that are able to produce tornadoes ...
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Effect of urbanization on weather events
At what stage is the studies on effect of urbanization on weather events (eg: Rainfall, Temperature, UHI) are now? There has been a number of observational and modelling studies around the world and ...
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Determining rotation of a bending detachment fault system
I would like to obtain the angle of rotation (𝛿θ) of a detachment fault (or oceanic core complex) after X meters of rock displaced during spreading at a mid-ocean ridge.
I have a differential ...
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Does hydroxyl radical chemistry in air quality models create numerical stability problems?
Atmospheric mixing ratios of the hydroxyl radical have relatively short lifespans (on the order of microseconds). When modeling air quality or the weather, the time step is usually much larger than ...
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Computing Isentropic Potential Vorticity from Hybrid Sigma Pressure levels
My task is to compute isentropic potential vorticity on a grid.
All data (ECMWF ens) are given on a hybrid sigma pressure grid.
Since I really cannot find reference, I assume (!) that relative ...
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Which equations describe complete (or near complete) behaviour of magma moving through rocks?
Yes this is a bit broader question but I want to know which processes play their role in movement of magma. If one wants to model magma movement through rocks, which processes should one not miss at ...
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Formula for numerical model for sustained warming in marine sediment?
I have been reading this paper and found simple numerical formulations to model the time duration, affected depth and amount of warming of marine sediments. The author uses a rudimentary estimate of ...
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Why should dynamical downscaling of meteorological data be made incrementally?
When downscaling meteorological data by using limited area models, many support forums recommended you to downscale incrementally in small steps. For example let's assume that your input data is on a ...
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How to set up a domain from namelist in WRF?
I'm fairly inexperienced with WRF and was wondering if anyone could point me in the direction of any helpful resources for it.
The task I have is to make a simple 9 km domain, but I'm having trouble ...
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What's the prospect of air quality forecasting based on machine learning?
Air quality forecasting models which are useful for atmospheric scientist and government can be built based on numerical theory or statistic theory.
The first approach outline the basic physics ...
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Numerical methods for solving shallow-water equations with a source
What are the numerical methods used for solving shallow water equations (PDEs) with a mass source, at the synoptic scales of the atmosphere, if I have a finite east-west boundary (may be periodic wave ...
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