Digital Geography

ALOS World 3D V1.1 vs. SRTM1

Some days ago a new version of the ALOS 30m DEM was released: Void pixels due to clouds and snow pixels within 60 deg. of north and south latitudes in Version 1 were complemented by existing DEMs. Out of the areas are same with Version 1 product. As we already compared ALOS with SRTM-1(I saw the ALOS DEM as “the winner”) I am now interested in how this performs in a another setting. We are changing our focus from Mongolia to Germany and check how the new ALOS DEM works compared with SRTM 1.

Short Announcement: QGIS 3.0 is on its way

QGIS 3.0 is the next big release in terms of features and tools. As it is stated in this e-mail chain we could expect this new major release in late 2017 and time is passing fast: retire 2.14 in June 2017 2.18 becomes LTR from June 2017 to 2018 3.0 feature freeze in July 2017 release 3.0 in Sept 2017 release 3.2 as next LTR in release 3.0 + 4 Months (eta June 2018) Yet this timeline is not strict and [was?] under discussion. We might expect a new candidate loaded with some cool and uncool features.

Map your family tree with Gramps and QGIS – how to digitize and visualize genealogy data

As I realized that I have a really huge family I was keen to digitize the current family tree and get into contact to my relatives. For getting things done, I choose the open source genealogy software Gramps to record all offline information about my family members and create a database as base for further investigations, updates and of course spatial visualization. After that, I exported a database view and visualized it with QGIS.

Some ways to produce topographic swath profiles

For a geomorphological study that I am working on I want to produce topographic swath profiles across a mountain range, that is, I want the average elevation along a profile plus the min and max values within a certain distance of said profile. I have used three different methods to achieve that and found some nice resources that I’d like to share with you: GMT – Generic Mapping Tools GMT is a powerful suite of command-line small programs to manipulate all kinds of geographic data (Wessel and Smith, 1998; Wessel et al., 2013). A walk through on how to produce…

QGIS and basemaps: QuickMapServices

To work in QGIS is very often much more convenient if you can use a basemap for your data. In the past we used and promoted OpenLayers plugin quite often but this was not the best out there as you saw often some issues with projections as well as with “lost tiles” in the map composer. So here is the new weapon of choice: the QuickMapServices plugin for QGIS.

Map your CV

Probably everyone at least once in your life was searching for a job and had faced the challenge of creating an interesting resume. But when you start to create a normal list-like cv/resume you will surely say “BORING! Next!”… As I’m a geographer the idea was to create map that is the CV itself.

QGIS 2.16 tutorial: georeferencing images

Since our last tutorial regarding georeferencing images in QGIS is 4 years old, let us have a second look at this task in the current times of QGIS 2.16. For this tutorial we will use a Soviet map of Crewe in England to see changes in city structure with a snapshot from 1957. We will use simple and quite easy affine transformations for this purpose.

PostgreSQL and PostGIS: A brief introduction

You probably seen this already (maybe on your very own PC as well): A folder with shape files. Well we’re living in the 21st century and I do have and use those folders still. After a talk of Sebastian Meier at Maptime Berlin I was convinced and started to work with a databases instead of folders. So let me show you how to install PostgreSQL along with PostGIS on Ubuntu and Windows, how to get data into it, import OSM data and how to connect it with QGIS/ArcGIS.

Import OSM Data Into A PostGIS Database (The Easy Way)

I often find myself in a situation where I want to work with large areas and datasets of OpenStreetMap data. No matter if you want to use them in a QGIS map or create custom map tiles in Tilemill, with the Overpass API you quickly run into performance issues. Imposm is a great tool to overcome that situation, so you can load OSM extracts (worldfiles in pbf format) with a custom data mapping into a PostGIS enabled PostgreSQL database. The downside: It is hard to set up if you are not a database and system admin guru. This is where…

From Cloud to GIS: Getting Weather Data.

Introduction In this post we are going to look at how to get weather forecast data and display it as a layer in a desktop geographical information system (GIS). The tools that you need are: A desktop GIS. I am going to use QGIS (free software) but I have done this with ESRI ArcMap as well A spreadsheet application. I will be using MS Excel but I have also tried this with Softmaker Office and I am sure LibreOffice (free software) will work or indeed any other spreadsheet application The Natural Earth Quick Start data set. This is a collection…