Questions tagged [bathymetry]
Bathymetry is the study of underwater depths
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Stepping artifacts - Merging raster data in ArcGIS Pro
I am working with a large number of raster datasets within multiple geodatabases in ArcGIS Pro. The original source data are imported from ASC format converted from UTM29N to WGS84 (Bilinear ...
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TypeError attempting conversion of txt file to las pointcloud format using pandas & laspy
I'm following this guide - https://pointly.medium.com/how-to-convert-your-point-cloud-data-into-las-laz-434ada0f1e99
Attempting a conversion from a txt file to las
My bathymetry data is in following ...
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Open data downloaded from EMODnet website on QGIS?
I've downloaded some bathymetric data from EMODnet website. The file format is .emo
I know it's possible to open in QGIS, but doesn't work for me. Drag an drop, open raster, open mesh.. nothing works.
...
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simpleKml: Adding polygons with multiple innerboundaries (works for Google Earth, not with Google Maps for Android)
This question is about simpleKml used to create bathymetric maps: On how to write the code to provide multiple inner boundaries for a polygon. And: To organize the kml with multiple innerBoundaryIs ...
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Wrong georeferencing in raster exported form .ovr file
I am working with a bathymetry that has been shared with me in .ovr format, when pulling to QGIS I realize that it has wrong coordinates, it is supposed to be at 20° latitude and it is at 0°.
I have ...
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How to extract contour lines from bathymetry profiles (mainly cross sections)
I need to extract contour lines from surveyed bathymetry profiles.
The profiles are .csv files with multiple points and X, Y and Z coordinates. There are cross sections and a single longitudinal ...
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Cannot show ocean bathymetry contour lines in Google Earth Engine
I am new to Google Earth Engine (GEE). Recently I hope to show the ocean bathymetry contour lines by using the ETOPO1 dataset.
Here is my code:
// Import ETOPO1 bathymetry dataset and choose a band.
/...
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QGIS: Converting Rasters (Bathyemtric ASCII & TIFF) to polygon
Currently using QGIS 3.16.
I essentially want to create a shape file polygon for the extents of bathymetric grids I am currently working with. The grids are high resolution (2m,5m,10m) and come in a ...
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Changing depth colorscale showing the intervals instead of only the minimum and maximum in print layout
I have made a legend with the bathymetry color scale in it
example:
It only shows 0 and -30 while I have made the color scale using 10 meter intervals, so 0, -10, -20, -30.
Does anyone know how to ...
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QGIS Apply Correction to Elevation Datum
I am wanting to apply a blanket correction to a bathymetry layer i.e. add 2m to every DEM cell. I assume I do this in the Raster Calculator but I'm unsure of the command line to use.
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QGIS Merge two DEMs of different resolution
In QGIS I am trying to merge 2 DEMs of different resolutions where there is a slight overlap between the two i.e. merging a bathymetry DEM with a topo DEM across a shoreline. As it is of a higher ...
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In QGIS change DEM elevations values from positive to negative
I have a DEM that currently has positive elevation values for bathymetry and negative values for those above sea level. How can I convert these cell values to negative for bathymetry and positive for ...
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Depth contour line using bathymetry
I am a very basic ArcMap user.loaded an ocean color .nc map in ArcMap, (the units of the map are surface phytoplankton chlorophyll mg m-3) on which i overlaid graduated symbols of some of my data. The ...
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Water depths map layer
Is there any water depths map layer available? I would like to have something like this:
I have tried satellite, but this is not so great to see depths:
var satelliteLayer = new ol.layer.Tile({
...
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How to combine a topographic DEM with an overlapping bathymetry
In QGIS, I had a larger DEM that captured the lake surface and a smaller DEM of the lake bathymetry. I spent a while trying to figure out smart ways to combine the two so as to replace the DEM lake ...
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Extract concontours from S57 features stored in SQLite3 file
I have a table where one of the columns is a set of S57 objects given as a data buffer (FEATURE field):
OBJ_ID CHART_FID FEATURE
0 441153270841366 102714 [, M, _, C, O, V, R, *, ,...
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Calculating water depth from ASCII file in QGIS
I downloaded ESRI ASCII file for bathymetry from GEBCO. Now I loaded the file as raster, then I clip the raster file according to my vector images (Image 1), then I did symbology, where I did single ...
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Average depth of linear features in QGIS
I have a shapefile with some linear features that I have drawn on the seafloor with QGIS. How can I calculate the depth of these in the field calculator (or another place)? I am looking for the ...
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Adding a CSV with GPS coordinates points and bathymetry data to Google Earth Engine
I'm trying to construct a bathymetry point map on GEE, and I want to import a CSV that contains bathymetry data.
The CSV that I'm about to import to GEE has the following columns: Latitude, Longitude ...
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How in QGIS to place the signature of the latitude and longitude of the map corner in the layout?
It must be done as in the example.
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Adding more values to legend on print composer tool of QGIS
I am creating a map with a bathymetry layer (raster) on the print composer tool of QGIS. On the legend it only appears the minimum depth and the maximum depth.
Is there a way on QGIS to show more ...
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What is the right geoid for calculating current sea depth from ECEF position and sea depth soundings
Let's say that I have an ECEF position (derived from GNSS, IMU, and barometric data) which is accurate to +-10cm. Let's also say that I have a chart of sea floor soundings, which, as unrealistic as it ...
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TIN interpolation out of extent [closed]
I have a problem with the TIN. I just started using QGIS because I no longer have access to ArcGIS. I want to create a reservoir bathymetry map from depth survey points. I created a polyline and ...
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Creating bathymetry maps using sonar data in SAGA
I am a geologist, however somewhat of a newbie to GIS.
As a personal project, I am looking to create some bathymetric maps of some local fishing lakes.
I am looking to do this using free open source ...
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My bathymetric sounder only exports to XYZ file want to input into GRASS
The export file has long, lat, elevation in a float format i.e. -70.8838319778442, 42.3222159164251, -14.6
The file is over 18 MB and each lat/long/elev is MOSTLY 1.5 meter apart and sometime maybe up ...
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Importing .bag (bathymetry) files into QGIS 3.x
I downloaded bathymetric data from the NOAA Bathymetric Data Viewer website: https://maps.ngdc.noaa.gov/viewers/bathymetry/
I've tried to import and view several .bag files from this website within ...
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Converting River Channel Cross-Section Data to Bathymetry
I have multiple surveyed cross-sections of river channels and need to convert this data into 3D polylines (shapefile) for use in a hydraulic model. The cross-section data is typically supplied in &...
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Problem with importing NONNA-100 bathymetry data into QGIS
Total QGIS newbie.
Tried importing Canadian Hydrographic Service Non-Navigational (NONNA-100) Bathymetric Data found here https://open.canada.ca/data/en/dataset/d3881c4c-650d-4070-bf9b-1e00aabf0a1d
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How to remove slope from DEM to better visualise topographic features of vriver systems in QGIS
I have a DEM of a river channel that i would like to remove the overall slope but retain features such as pools, riffles, bars etc. I have used the River Bathymetry Toolkit (detrending tool https://...
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Wrapping a GeoTIFF over the antimeridian in QGIS
I want to make a map of marine sampling locations for a study, and in this context show some bathymetric profiles. So in my map I have shapefiles from NaturalEarth as well as GeoTIFF bathymetry data. ...
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Creating a greyscale bathymetry map of the world in QGIS
I am looking to create a greyscale bathymetry map of the world in QGIS which I can then output as SVG contour lines. Maybe there is somewhere where I can find and download greyscale vector tiles of ...
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Opening multiple text files into a single .tab file in MapInfo
I am trying to open multiple xyz text files into mapinfo to create a table where i can create a raster image of multibeam bathymetry.
Is there a script which will open each .txt file and merge them ...
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How to count points of a point layer (shp) for each depth class of a bathymetry vector layer
I am using QGIS 2.8.3 but also have 3.4 whatever works better for this issue.
I have a bathymetry shapefile and a point layer. One of the columns of the bathymetry vector gives the maximum depth and ...
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Getting data from Humminbird ChartSelect .bin file [closed]
I purchased some lake bathymetry data from humminbird chartselect. I can see those data using their applications such as FishSmart or also using the humminbird sonar module. But I would like to read ...
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Opening Lowrance .at5 files in Mac/Linux/Windows
I have some bathymetry data in Lowrance .at5 format. I would like to read those data to my computer and process it (convert it into point cloud etc). Is there any software available to do so? Or is ...
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Mean lower low water (MLLW) for tidal correction
I am estimating water depth (bathymetry) using satellite data over a US water. I have obtained tidal values (datum is MLLW) as at the time of satellite overpass to correct my satellite-derived ...
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Integrating sea level curve data in a bathymetric grid
I am attempting to apply these data recording where sea-level was in the Gulf of Mexico (in meters below mean sea level) over the past 20,000 calendar years at a 500-year resolution in ArcMap:
What ...
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Pictures with isobaths to a 3D Model in a Browser
I have pictures of lakes with isobaths (*). The result should be a 3D model in a browser.
I tried to make a vector image, but this results in a SVG. I can not import it.
How do I make a layer of the ...
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Combining Bathymetric and Elevation Data using R?
Here is some elevation data of some islands.
I wish to add depth info to the water. With the generous help of @Spacedman at Overlaying elevation data and bathymetry data in R? I get:
To resolve the ...
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Overlaying elevation data and bathymetry data in R?
I have two layers that cover approximately, but not exactly, the same area.
One is land elevation of some islands. The other is the depth of the water around the islands. I can resolve the vertical ...
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How to Loading BAG file format in QGIS
I need to load a BAG file (Bathymetry attributed grid) in QGIS (3.4) according to the supported file page https://www.gdal.org/formats_list.html it is supported, but is not compiled by default and ...
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How do I compare multiple years worth of geomorph changes in a river while drawing one profile line?
I have many years worth of DEMs of a river I'm studying.
I'm very, very new to ArcGIS (think one intro class), and learned how to use the 3D analyst tool.
What I'd like to be able to do, is to draw ...
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Reading bathymetry for coordinate with Python? [closed]
I need the water depth at specific coordinates and my geoscientist are offering me a dataset in either TIFF or XYZ/txt format with data points each 2km.
I will typically be extracting about 1000000 ...
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How to correct depth values with tide data? [closed]
We are trying to derive bathymetry using sentinel images using QGis 2.18.
The training data is from a boat gps track taken in 2 days. The depth value captured needs to be corrected for tidal ...
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How to separate or cut the elevation from bathymetry raster TIFF file with vector layer coastline in QGIS 3.4.3?
I have a raster GeoTIFF file downloaded from GEBCO 2014 which contains bathymetry and elevation.
I need to split in 2 layers the raster GeoTIFF file (layer: Bathymetry and layer: Elevation) using ...
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How can I change the elevation of a lake on a DEM so I show the lake bottom contours?
I'm studying the drainage of a lake and I have a DEM of the lake and the surrounding area. I already identified the shorelines of ancient lake levels at higher elevations, but I would like to keep ...
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Getting bathymetric contours confined only within river banks using QGIS?
I have bathymetric survey data in the form of XYZ. X and Y are coordinates while Z is river bed level (elevation) from a datum. These are about 14000 irregularly located points within a river. Now I ...
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Measuring distance from gridsquares to contours of a shapefile
I have a baselayer (.shp file), with bathymetric contours. I want to measure the distance from each grid square in a grid, to the nearest nominated depth (so was hoping to have a way to also nomate ...
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Trying to interpolate depth measurements of a pond
We have taken depth measurements across a pond, and have a CSV file with each location's GPS coordinates and depth in meters. We are trying to create a map of this pond showing where the channel is ...
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SRTM/DEM 1m resolution (batymetri) to point [closed]
I have bathymetry data (1 huge data) =
SRTM/DEM/FGDBRaster (0,9818m resolution pixel, floating, 32 bit, 45 GB size)
and an alternative data (split into small pieces data) =
same data but with 1m ...
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