Questions tagged [antimeridian]
The antimeridian, or 180th meridian, is the meridian which is 180° east or west of the Prime Meridian with which it forms a great circle. It is distinctive among meridians in that it is common to both east longitude and west longitude.
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Vector files in QGIS are very badly deformed in different projection systems [duplicate]
I have a vector file of a world map, a shapefile. I wanted to make a map of the world centered on the Pacific Ocean, so I used EPSG:8859 BUT the Arctic and Antarctic regions will undergo severe ...
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SQL Server WKT crosses antimeridian - sqlgeography looks normal, sqlgeometry does not
I have a WKT that crosses the antimeridian and is stored in SQL Server as a geometry. But when I read it back out it is stretched/skewed. If I take the WKT from the geometry, and create a geography ...
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Seeking global map projection centered on Americas
I currently use EPSG: 4326.
How can I re-project the map so that the blue delineation appears as one continuum, rather than being split into a western and eastern component?
EPSG:3832:
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gdalwarp antimeridian issue
I realise there are similar questions but I could not find the exact same.
Here is what I am trying to do:
gdalwarp -t_srs '+proj=stere +lat_0=YY +lon_0=XX +k=1 +x_0=0 +y_0=0 +a=1737400 +b=1737400 +...
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PostGIS: geometric shapes crossing 180 meridian
How to deal with a problem of intersection of geometry shape (linestring, polygon) and 180 meridian?
I have polygons distributed all over the Earth globe, some of them intersecting 180 meridian.
The ...
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PostGIS - Polygon crossing latitude 0 and longitude 180
I need to find all the couples long/lat (listed in a table) that belong to the area defined by a polygon in PostGIS (version 3.0). My area is defined by the following polygon, which crosses the ...
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Grid of meridians and parallels from South Pole in QGIS print composer
In QGIS 3.16, I'm preparing a map of the emperor penguin colonies in the Antarctica, using the data from the Quantarctica project, but I'm facing a couple of issues with the grid created in the print ...
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Create geo-referenced raster crossing dateline in Python
I am trying to create a geo-referenced raster from data that crosses the dateline. In one example my data runs from 11-69N, 150-210E. I am pretty new to both Python and creating rasters, but have ...
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Minimum Convex Hull Crossing 180 degrees INDL
I've come across several similar posts trying to solve this issue or variations on a theme:
How to build a minimum convex hull crossing the 180 degrees line?
QGIS displaying polygon that is crossing ...
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Reconstructing satellite sensor swath polygon (multiple orbits, antimeridian crossing)
I'm currently working on a project that involves displaying a given satellite's sensor coverage of Earth, with one of the objective being to count how many swaths overlap a given point on Earth over a ...
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Leaflet making ap invisible out of the world's edge
I am working at zoom bounds to my map.
Unfortunately, if I go beyond the min zoom 2.75 I start to see the map beyond the World's edge. I mean, that the world map tends to be repeatable, but without ...
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Leaflet Shiny and polygons across the dateline
I have a Shiny app which maps country characteristics to their SF polygons (from rnaturalearth) using Leaflet. I'm having trouble displaying the polygons around the dateline (antemeridian) in the ...
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Cannot split vector across the 180degree line in QGIS
I am trying to split the vector I imported from geojson across the 180degree line and it gives me an error:
No features were split : If there are selected features, the split tool only applies to ...
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QGIS Vector layer stretched across entire map
I've imported a vector layer with extents between two hemispheres near the antimeridian. Unfortunately, instead of having the geometry split in two, where one part lies east of the antimeridian, and ...
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Reprojecting over the Pacific Ocean with EPSG:3832 gives artefacts
I am trying to center the Natuarl Earth 10m on the Pacific. I have followed instructions from QGIS Tutorial: How to Change the Map Projection to be Centered Over the Pacific Ocean.
When I change ...
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+0-180 degrees of mesh layer are displaying as horizontal lines [QGIS]
I have been trying to display weather data from ECMWF in QGIS on top of a base map, but half of the heatmap rendered from the mesh layer (imported via grib) displays as straight horizontal lines.
I ...
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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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How to reproject data from [-180 180] to [0 360]? [duplicate]
I have both a GeoJSON and shapefile of volcanoes along the Pacific Ring of Fire. The area I want to render in the map is right around the antimeridian, so Leaflet cuts it in half. I initially tried to ...
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Control direction of lines around earth
in QGIS 3.4.14, I am trying to draw a line from Los Angeles to Tokyo. With an XYZ Tile base map turned on, the line goes east from Los Angeles (over Africa) to Tokyo. I would like the line to appear ...
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Changing projection from 0 360 to -180 180 for a simple raster
I'm trying to convert a raster with projections of (0, 360) to (-180, 180), and I've tried various SO solutions such as this, but it gave me a cropped output that doesn't have the western hemisphere.
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GDAL VectorTranslate creates shards/fragments along anti-meridian
I have challenge to take a GeoJSON file and convert the CRS to WGS84/EPSG:4326 and also split the polygons along the anti-meridian. These are both in preparation for presenting the data via mapbox....
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Making XY To Line not give shortest distance in ArcMap
I am creating a very simple map through XY to Line in AcrGIS. However, since the destination is New Zealand and located at the bottom corner of global maps it creates the following.
Is there a way ...
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Removing 180th meridian line on map of Russia?
I'm not sure how to remove the line that represents the 180th meridian (international dateline) on my polygon. I have the "Russia Country Boundary 2017" feature layer added from the Living Atlas. My ...
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Removing a 'non-gap' gap from a polygon that straddles +/- 180 longitude; looking for an R-based, code solution
I am working with a set of polygons from here: http://lme.edc.uri.edu/index.php/digital-data. In the artic, there are several polygons that straddle the +/- 180 longitude line.
These are single ...
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GDALWARP cuts off right edge of image?
I'm reprojecting GFS GRIB files to EPSG:3857 using gdalwarp. Resulting file get little bit shorter to the right so when I zoom in from zoom level 5 and higher, I can see vertical line with missing ...
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Get a bounding box of a geometry that crosses the antimeridian using OGR
I'm trying to get a bounding box of the geometry that crosses the antimeridian using OGR:
from osgeo import ogr
geom = ogr.CreateGeometryFromJson('{"type":"MultiPolygon","...
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PostGIS geography returns area < 0.0
I am trying to convert a geometry column to a geography column and calculate the area using this query:
SELECT dccode,SUM(CAST(St_Area(geom::geography,true) AS NUMERIC)) as Area
FROM schema....
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How to generate a Global Voronoi diagram?
Using arcMap, QGIS and similar software it is easy to create a non-global Voronoi diagram.
The resulting shapefile polygons however are showing weird behavior when crossing the -180 meridian or the ...
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Reproject with shifted central meridian - dateline gap in ArcGIS
I have reprojected a file of global ocean zoning to Winkel III shifting the central meridian to -180 to center it on the Pacific using ArcGIS 10.5. Doing so, a gap at the dateline appears:
In a ...
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Removing lines from a polygon that has been reprojected to cross the antimeridian
I have a polygon file in qgis3.0 representing global tectonic plates. I have reprojected the original file in WGS84 (EPSG:4326) to PDC Mercator (EPSG:3832) using only the features that are needed.
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data reprojection and the antimeridian
I am trying to produce an earthquake map of the south-west pacific ocean area around New Zealand and its surrounding islands.
In order to produce a map which crosses the antimeridian, I took two ...
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Line through polygons spanning 180-degree line
In ArcMap 10.2, I am trying to render a shapefile with polygons in the Pacific Ocean, which span the 180-degree line. The resulting image shows a line going through the polygons at the meridian, and I ...
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Hibernate spatial intersects() over antimeridian
I have a DB full of objects that contain a location (usually a polygon). I have a query defined that uses Hibernate Spatial's intersects() method to find all the objects that are with a box that's ...
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How to display the geojson polygon after 180th meridian in leaflet?
Like the vector grid plugin in the leaflet:
http://leaflet.github.io/Leaflet.VectorGrid/demo-geojson.html
see the above example at zoom level 1 or 2
Is there any way to display geojson, not as a tile ...
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Determine whether a polygon crosses the antimeridian
I'm working on a system that uses bounding boxes as a fast first check for a point-in-polygon filter. My current naive implementation (just taking the min/max lat and lng for all points) fails on ...
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Does exist a Python library to generate polygons avoiding antimeridian issues?
If I need to generate a polygon that crosses the anti-meridian, does it exists a Python library that treat such cases (partitioning such polygon and generate a multipart polygon)?
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Is there an inverse operation to ST_Shift_Longitude in PostGIS < 2.3?
ST_Shift_Longitude(geom) (renamed to ST_Shift_Longitude in PostGIS 2.2) adds 360 to longitudes below 0, thereby (for lon-lat coordinates like WGS84) moving the part of the world "left" (west) of the 0-...
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Is it possible to wrap date line with gdal.VectorTranslate()?
I use '-wrapdateline' option in ogr2ogr to split the polygons at the anti meridian. But in ogr2ogr Python port bWrapDateline is hardcoded to False.
Is there a way to pass 'wrapdateline' option to ...
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Transforming a shapefile from EPSG:3338 to EPSG:4326?
I'm trying to transform this shapefile from EPSG:3338 (Alaska Albers) to EPSG:4326.
When I display the file in EPSG:3338 in QGIS it looks as you'd expect:
But when I display it in EPSG:4326 I see ...
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Define polygon across the 180 meridian in DotSpatial
I am new to DotSpatial and I try to define a polygon that crosses the 180 meridian by following:
FeatureSet fs = new FeatureSet(FeatureType.Polygon);
Coordinate[] coord = new ...
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Un-splitting data that crosses antimeridian in ArcMap?
I'm working with a set of points in ArcMap that crosses the antimeridian (180°). I need to convert the points to a line but doing so creates a line that doubles back and forth across the globe to ...
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Shapely polygons crossing the antimeridian
Sample data
Consider the following WKT Polygon, crossing the international dateline (antimeridian):
POLYGON((176 49,-65 49,-65 11,176 11,176 49))
And the following points:
POINT(-140 32) # Inside the ...
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Use map projections to find closest point over dateline
I want to identify closest points to a polygon over the dateline in an OGR/Python script. I found this workaround for PostGIS but I'm not 100% certain about the applicability in my case. This may be ...
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How to use postgis to reproject 900913 to a different bounding box
The OSM data is in 900913. I need to get 4326, but so that the longitude's range is NOT -180..180, but rather some other, shifted range, based on a parameter. This way, if I need to draw an object ...
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GeoJSON<->TopoJSON roundtrip breaks leaflet on antimeridean
For Wikipedia, I'm writing a service that extracts polygons of a country by a given ID, simplifies them, and produces GeoJSON. The PostGIS query produces this GeoJSON:
{"type":"MultiPolygon","...
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xarray slicing across the antimeridian
I'm just starting with using xarray for working with n-dimensional NetCDF datasets. I particularly like the techniques for slicing using both indexes and labels (isel and sel):
import xarray as xr
ds ...
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Unwanted display of 180 meridian in map [duplicate]
When I use the WGS 84 CRS the Chukotka peninsula east of the 180 meridian is shown on the left of the map. If I project (on-the-fly) the map using a Lambert Azimuth projection, the Chukotka peninsula ...
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Best-practices for databases and APIs with geographic data spanning the antimeridian
What is the best-practice for storing geographic features (lines, polygons and their multipart equivalents) when these features span the antimeridian (±180° longitude), and need to be sent to and ...
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How can I convert PostGIS geography to geometry and split polygons that cross the antimeridian
I have a PostGIS 2.2 table that stores polygons as geography type. The table contains several polygons that cross the antimeridian. I would like to split these polygons at the antimeridian and ...
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Polygons across international dateline [-180..+180 longitude]
I'm trying to generate polygons for satellite orbital swaths.
So far I have a method to generate two lines which represent the edge of each swath in [lat,long]. Some of the swath's cross the ...
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