Creating elevation profiles and other raster cross-sections using GDAL and the two-point equidistant projection +++
Recently I was looking into making some elevation profiles and other types of cross-sections of GeoTIFF files hosted in the cloud. The idea was rather simple, draw a line on a web map and then an elevation profile (or some other thematic cross section about land use, soils, NDVI, etc) would be...
Introducing PostGIS Baselayers: Automatically import Natural Earth, Geonames, GADM, and other popular vector datasets into a PostGIS database +++
This an introductory post about [PostGIS Baselayers](https://github.com/kokoalberti/postgis-baselayers), which is a web application I've been working on that downloads and imports popular vector datasets (Natural Earth, GADM, Geonames, etc) into a PostGIS spatial database with the click of a...
Experiments with the global JAXA ALOS World 30m elevation model on AWS S3 +++
So yesterday I was looking into a global 30m elevation model called the ALOS Global Digital Surface Model (AW3D30). It is from 2016 and produced by the Japanese Aerospace Exploration Agency (JAXA). Supposedly it is a pretty [decent...
GIS data and digital maps for hiking in the mountains of Lapland in Northern Sweden (Kungsleden, Sarek and Padjelanta National Parks) +++
If you've ever done (or plan on doing) any hiking in the Arctic mountains of beautiful Lapland in Northern Sweden, you'll be familiar with the wonderful purple-colored Fjallkartan maps published by Lantmateriet. The hardcopy maps are essential when you're up there, but lately I've found myself...
Hosting and accessing cloud optimized GeoTIFF files on AWS S3 - A practical guide using the EU-DEM elevation model +++
There are lots of great geospatial datasets available online, but accessing this data automatically and at scale is often difficult, and manual access usually takes a bit of work to download and sort it all. You'll have to register for some silly data portal, pick out the tiles that overlap...
First look at Planet imagery of the Brumadinho (Brazil) dam collapse +++
This weekend news hit of a tailings dam collapse at a mine owned by Vale in Brumadinho, Brazil. From the initial reports and photos coming out of the area the damage looked immense.
Because news reports were sparse on geospatial details that show the extent of the disaster, I started looking...
Georeferencing and digitizing old maps with GDAL +++
While cleaning up some old USB drives I found several scanned images of wartime maps of my home town The Hague. I quite like the cartographic style and decided to digitize the maps using GDAL and turn them into a web map. This article explains how to do that, compares some of the different GDAL...
Guide to GeoTIFF compression and optimization with GDAL +++
With the fast ZSTD compression (GDAL 2.3 and above) and Limited Error Raster Compression (GDAL 2.4) becoming available in our favourite geospatial toolkit, I thought it would be interesting to run some benchmarks and write a guide on compressing and optimizing GeoTIFF files using the latest...