Modeling Effluent Disposal Mixing Zone into the Ocean with OpenFOAM - Tutorial

A right assessment of the effluent mixing zone would require a baseline of sea currents, discharge flows, seawater and effluent density, bathymetry, waves, infraestructure geometry and a tool that can analyse the interaction of the mentioned factors. OpenFOAM is a numerical model for Computational Fluid Dynamics (CFD) modeling capable of modeling fluids with complex geometries, conditions and requirements; with OpenFOAM one can model compressible/uncompressible, single phase / multiphase, flows that mix, non-newtonian flows, etc. OpenFOAM comes with build-in tools for model construction and visualization, and there is Salome Platform for advanced mesh generation.

This tutorial show the entire procedure for the simulation of a effluent of 40 l/s into the ocean that has a current of 0.05 m/s. The model is on transient conditions, model simulation were done under uniform discharge rates, the development of the mixing zone was analyzed with paraView tools and a water chemistry component was introduced into the simulation with some Python scripts. 

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Comparison of IMERG Precipitation with Station Information with QGIS, Python and Pandas - Tutorial

There are tools for temporal data analysis like Python, IPython and Jupyter; there are tools for spatial data analysis like QGIS. But, are there tools for spatio-temporal analysis? Unfortunately no, but there are good approaches to manage spatial data in Jupyter or to run IPython in QGIS3. These approaches aren't a complete ansqwe to the current demands of big data processing in few computational time with simple scripts, but by sure it will help to shape better solutions.

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OpenFOAM Model Local Mesh Refinement with Salome and Python3 - Tutorial

Discretization is the “art” of transforming a continuous media as nature into discrete parts; for numerical models the spatial and temporal discretization have become a key issue in assuring model efficiency, output precision and the overall quality of the modeling work. Flow models are constructed to represent an specific requirement on the surface water/ groundwater flow regime (local scale), however, the model has to represent first the overall flow regimen (global scale). On the general model areas, an efficient spatial discretization criteria rules to keep the mesh elements as big as possible, meanwhile, in the areas of interest the model should be discretized into the smallest parts.

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Direct NASA IMERG precipitation images download in QGIS3 with Python

The new version of QGIS is QGIS3 and it runs with Python 3 which introduces some change on the interaction with webservers with package “requests”. For those that are new to the IMERG images, those are some kind of the new TRMM images with precipitation estimation from multiple passive microwave (PMW) sensors on various precipitation-relevant satellites starting in March 2014. The IMERG images have a pixel resolution of 0.1 degrees and a temporal scale of 30 minutes; on the current panorama of precipitation estimates based on satellite-gauge, the IMERG data product with the highest spatial and temporal resolution available over the last 4 years.

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Massive Operations on Rasters with QGIS3 and Python - Tutorial

There are new available tools and resources to understand climate change, land use dynamics, water cycle and other parts of our physical environment. Many spatial data come on raster format and are available on web servers, those servers have a image register every year, every month, every day, hour, half hour or minute. If we want to assess a physical phenomena we have to be able to analyze large set of data.

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Object / fluid interaction modelling with OpenFOAM - Submarine Case - Tutorial

This tutorial will apply OpenFOAM to simulate the flow effect on submerged object using the simpleFoam solver and the k-epsilon turbulence schema. The tutorial develops the case of a submarine model against a flow current; the velocity and pressure applied on the submarine will be analyzed on the model results and flow paths will be plotted to see the main patterns around the submarine. Model output visualization is performed on Paraview that allows the representation of velocity and pressure vectors over the submarine.

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Energy Dissipator Modelling in Open Channels with OpenFOAM - Tutorial

This tutorial will demonstrate the modelling configuration to simulate a power dissipator in an open channel. The dissipator design is proposed on the Stormwater Drainage Manual from the Drainage Services Department of Hong Kong and  OpenFOAM will be used for the simulation with the interFoam solver since two immiscible and isothermal fluids are involved (water and air). The main variable of interest on the dissipator simulation is flow velocity to assess the efficiency of the dissipator.

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How to download and use the LocClim software to estimate climate - Tutorial

LocClim is a software developed by the Agrometeorology Group of the Food and Agriculture Organization of the United Nations. The software provides an estimate of climatic conditions at different location regardless of the availability of observations. This software is of great importance if you want to know the climatic conditions of certain location and you do not have available observation points. It is possible to modify the stations that provide the data, so you can control the accuracy of the estimates. This tutorial demonstrates how to download the New LocClim software, how to find a location and how to export the resulting data.

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Downloading and preprocessing Sentinel 2 images using the Semi-Classification Plugin in QGIS 3.0

Sentinel-2 carries an innovative wide swath high-resolution multispectral imager with 13 spectral bands (443–2190 nm) (European Space Agency). Sentinel images have a swath width of 290 km and a spatial resolution of 10 m (four visible and near-infrared bands), 20 m (six red edge and shortwave infrared bands) and 60 m (three atmospheric correction bands) (Satellite Imaging Coorporation).The images are very powerful and are of great relevance for land and water management because analyses can be done from the spectral bands, natural color and false color image can be visualized and spectral indices can be obtained. Therefore, downloading them for free is an incredible opportunity for scientists and analysts to meet their goals. This tutorial demonstrates how to download and preprocess Sentinel 2 images using the Semi-Classification Plugin in QGIS 3.0. In addition, how to install the plugin is explained.

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How to insert a background image in ModelMuse - Tutorial

It is very common that before we start doing the modelling in Model Muse, we first begin with a geographic information system like QGiS where we can see our data and define the information we are going to import into ModelMuse. We usually use background images for a better understanding of where we are located, what we are seeing and how this terrain may be affecting our results. 
It is also useful to have a background image in ModelMuse as we do in QGIS in order to ease the analysis of the simulation results in the software. In this tutorial we will show you how to do this in a very simple way so you can apply it in future models.

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How to model a contaminant plume with ModelMuse and MT3DMS - Tutorial

MT3DMS Is a modular three dimensional transport model that can be coupled with Modflow to simulate the concentration changes of miscible contaminants in groundwater considering different processes like advection, dispersion, diffusion and some chemical reactions.

By studying how the contaminants behave in groundwater we can determine influence areas and use this information in prevention plans to reduce contamination in order to achieve a sustainable management of aquifers.

In this tutorial we will show how to set up a MT3DMS in simple ModelMuse model in order to evaluate the degradation of the contaminant coming from a source.

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Labelling and Clipping using Hydrologic Information of a Basin in QGIS 3.0 - Tutorial

Presenting Geographic Information Systems (GIS) is of great importance to transmit the correct ideas of the analyzed information. QGIS 3.0 is a powerful software to design and present maps. GIS can contain diverse and vast information; however, the analyst should decide what to present and how to present it. Therefore, labelling is a skill that must be developed when creating maps. This tutorial shows how to clip features to the shape of the study area and how to label the features of interest. The study area is a basin within the state of Tlaxcala, Mexico and it has a channel network shapefile and points with the name of the channel network features. The explanation includes how to create an expression to label the features using conditionals and how to change the style of the labels using QGIS 3.0.

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Particle Tracking Simulation with Model Muse and Modpath - Tutorial

MODPATH is a particle tracking post-processing package that computes and displays three-dimensional pathlines based on output from MODFLOW. These pathlines help us to see the expected transport trajectories coming from a specific contaminant source. In addition, we can also use this package to obtain the time that these pathlines will take to reach a particular point. 

In this tutorial, we will show how to set up MODPATH to see the movement of particles over time coming from a  contaminant source and how these can be influenced by factors like the presence of low permeability areas.

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How to obtain a Basin, Channel Network and Flow Accumulation from a Digital Elevation Model with no sinks in SAGA GIS and QGIS 2.18 – Tutorial

A basin is defined as a topographic region in which all water drains to a common area. Identifying basins within a study area can be beneficial for land and water management because priority areas can be defined and the hydrology of the area can be visualized. Delimiting a basin can be done by using Geographic Information Systems such as QGIS and SAGA GIS. To do so, a Digital Elevation Model (DEM) is required since the drainage network is determined by the elevation and slope of the terrain. This tutorial demonstrates how to reproject a DEM raster in QGIS, how to fill the sinks of a DEM, to calculate flow accumulation, to obtain the channel network and the basin limits with SAGA GIS based on the DEM using the Upslope Area interactive tool.

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Downloading a Digital Elevation Model (DEM) from NASA EarthData –Tutorial

The terrain properties of a study area are of great importance due to the vast information they provide for water and land management. The elevation values can be obtained by advanced spaceborn techniques such as the use of remote sensing from satellites. On June 29, 2009, NASA and the Ministry of Economy, Trade, and Industry (METI) of Japan released a Global Digital Elevation Model (GDEM) to users worldwide at no charge as a contribution to the Global Earth Observing System of Systems (METI and NASA, 2011). This tutorial is a demonstration of how to download a Digital Elevation Model (DEM) from the ADVANCED SPACEBORNE THERMAL EMISSION AND REFLECTION RADIOMETER (ASTER) Version 2. In addition, how to merge two DEM rasters and how to change the style of them in QGIS 2.15 will be shown.

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How to export MODFLOW Results from Model Muse and import them into QGIS - Tutorial

ModelMuse is a versatile software that helps us with the creation of MODFLOW input files, running the model and the visualization of simulation outputs. These results give us a valuable amount of information that, by analyzing it correctly, can be used to take management decisions regarding the sustainable use of aquifers. These analysis encompass many different types of information which complement the groundwater modeling results.

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Groundwater Modeling as an Example of Modeling As A Product (MAAP) - Advantages and Limitations

On a conversation with a colleague we have discussed the potential of selling groundwater modeling through the Internet. The idea (that is not so new) to develop groundwater models from remote areas optimizing the human resources, logistics and time involved on the evaluations its kind of the next step in numerical modeling but it has some arguments to be discussed for its implementation. From the management point of view, if we focus on mass production from and if we take into account theoretical concepts of business administration the idea of outsourcing tasks can be ideal for the success of a company or industry; however from the hydrogeological point of view there are serious complexities on the groundwater flow regime analysis, limitations on the input data and skills deficiencies that put the hydrogeological evaluation in risk if we work a groundwater model online.

In a global world we can make video call to almost anywhere for a reasonable price and our need/disponibility of broadband is always increasing but our ideas are not well conected and the group ideas are more distant than religion beliefs, therefore the method of developing a groundwater model could be of great importance in the quality of the groundwater evaluation through numerical modeling. This article discuss some key aspects of developing a groundwater model as a product (MAAP) and review its advantages and limitations.

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How to insert Topography Data from a Digital Elevation Model into Model Muse - Tutorial

When studying the groundwater flow, one of the main factors that influence its behaviour is the topography. Nowadays, we can obtain this topography information from several sources, being GeoTiff one of the most popular elevation models format file.

Model Muse is a versatile MODFLOW graphical user interface (GUI) where it is possible to insert many boundary conditions and terrain characteristics in order to represent the real conditions of the groundwater flow in an accurate way.

In this tutorial, you will be able to learn how to import digital elevation model data into Model Muse so it can be assigned as the topography of the area and take part into the simulation.

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Arid Zone Determination on Global Scale with IMERG Imagery and QGIS 3 - Tutorial

An arid region is defined as a land that has little to no rain and it is too dry to support extensive vegetation. Arid regions are common in our planet and those are located on specific latitudes as a product from the atmospheric global circulation, topography and other factors. Even tough arid regions are too dry, it doesn't mean that an extensive amount of people do live in these arid regions or their economical activities depend on those areas.

As zones located close to rivers are vulnerable to flooding, the arid zones and its water resources are vulnerable to global warming. Changes on the spatial and temporal precipitation distribution with an increase on temperature can lead to drastic changes on the surface flow rates and the groundwater flow regime.

As a deeper introduction to the existence of arid regions, there is a animation from the NASA's Global Precipitation Measurement mission that unifies the precipitation measurements of 12 satellites and integrates them into a Integrated Multisatellite Retrievals for GPM data product (IMERG). The animated data visualization is from April though September 2014 and shows the global distribution of precipitation as rain (liquid) or snow (frozen). 

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How to decrease the Raster Resolution in QGIS3 - Tutorial

A raster is a rectangular pattern of rows and columns with a spatial georeferentiation. On a raster each cell contains a value that is uniform in the cell geospatial extension and its the most used spatial data model when we deal and analyze spatially distributed values as land cover, precipitation or population density.

Spatial analysis on raster deals with raster resolution or cell size. As smaller the cell size, the result from the analysis will be finer however the raster file size will be much larger; if we use coarse cells, the raster file sizes will be smaller but the results could be poor for the objectives of the analysis. An equilibrium in between the raster resolution and the raster file size has become a topic to have in mind for beginner GIS users as well as for experienced GIS users.

QGIS is a free and powerful Geographical Information Software (GIS) software. QGIS comes with a variety of tools to manage vector and raster spatial data and its capabilities can be increased when it couples with Grass, SAGA GIS, OTB and its plugins. This tutorial show the simple procedure to change the raster resolution in QGIS 3.

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