Digital Geography

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…

Some ways to produce high-res DEMs – tools and data

Many of us use digital elevation models (DEMs) for a whole bunch of different applications. There are some standard products which everyone should know, like SRTM1, SRTM3, ASTER, GLOBE or ETOPO1 for the land surface or GEBCO for bathymetry. However, they have a relatively low resolution and are therefore not suitable for all purposes. During the last few years there has been a huge progress in producing much better DEMs, especially local ones, using a wide range of techniques like LiDAR, photogrammetry, image correlation, structure-from-motion (SFM) etc. Some of these techniques make use of powerful, but expensive equipment (e.g., LiDAR),…

Open Data in the UK

The Ordnance Survey is UK’s mapping agency and frequently releases free datasets. Their OpenData policy is quite progressive compared to Germany’s and they’ve recently published some fresh datasets that anyone can use. All you need to do is to register and to acknowledge them. The new datasets are: OS Open Map – Local; OS Open Names; OS Open Rivers; and OS Open Roads. They include data on urban and rural features, an index for all the location names in the UK, a generalised open water network, UK’s connected road network and much more. All this adds up to their existing…

Google Earth Pro is now for free!

Google recently made an announcement that left me very happy: Google Earth Pro, the enhanced version of the world’s most popular digital globe, is now available for free. The software comes with some additional features compared to classical GoogleEarth and used to be $400 per year – actually many users paid because the benefit was huge. Now all you have to do is to register, get a free key, and download the software. If registration doesn’t work for you, don’t worry and don’t give up. It didn’t work for me when I tried first, the next day I tried again…

Mapping earthquake environmental effects

In contrast to magnitude, which describes the energy release of an earthquake, the intensity of a seismic event describes its effects. Obviously, the intensity value depends on the location of the observer, on the earthquake parameters, but also on what is used to ascribe earthquake effects. Many scales exist. Most macroseismic intensity scales are based on earthquake damage to buildings and infrastructure. The MM and, especially in Europe, the EMS-98 scales are widely used.  All these scales that take into account damage to man-made structures have at least four problems in common: It is hard to compare building types world…

Peakfinder – identify the hills around you

Peakfinder.org is a fascinating website. It’s not new, but I just came across it few days ago by a recommendation of @callanbentley. It appears very simple, very clever and very beautiful. The site allows you to find peaks (mountains and hills) in your surroundings or wherever you want. Basically, it draws a simple line sketch of the horizon as you see it from your current position and names all the peaks in your sight. I could spend hours on this.  The website’s layout is amazing. It’s calm, pure and perfectly organized. Some options include searching for peaks from a database and…

short announcement – Digital Landscapes session @EGU2014, Vienna

At the EGU2014 in Vienna (27 April – 2 Mai, 2014) a session on Digital Landscapes (GM2.1) will be convened by J.K. Hillier, P. Tarolli and S. Conway. The session “aims to bring together ‘users’ analysing digital landscapes to exhibit the best quantitative methods and computational techniques, cross-fertilize best practice, and illustrate what can be achieved and what challenges remain.” (http://meetingorganizer.copernicus.org/EGU2014/session/14779) The conveners especially invite Early Career Researchers (ECRs) to participate. This session is also a PICO session – Presenting Interactive COntent. So if you go to EGU, consider submitting an abstract there (until 16 January!) and don’t forget to…

Analog Geography – German soil of the year 2014 is the vineyard soil

Sometimes you need to replace bits and bytes with dirt and soils, and today’s news are really pushing me to leave the desk and to go for a walk. Every year, the Deutsche Bodenkundliche Gesellschaft (German Pedological Society) announces the Soil of the Year. Next year’s soil is the Vineyard Soil! It’s not only one, but a whole group of soils known for their high fertility and their anthropogenic, mineral rich R-horizons. In Germany, those R-horizons formed as early as in Roman times in some regions, since the Romans brought the civilization wine to Germany. Currently, I am feeling a…

GPS Visualizer – a great online tool for GPS, GoogleMaps and GoogleEarth issues

I looked for a program to draw circles of a pre-defined radius around some points on earth I had the coordinates from. A quick search returned the website GPS Visualizer, and I absolutely love it! It is not only a great free website to convert GPS data in formats that can be used in GoogleMaps, GoogleEarth, jpgs and many other formats, it also allows you to customize maps very easily. Plus, you can use a large number of different maps as base data layer. It looks like the site has been created to deal with tracks and waypoint data, but…

short announcement: The Mercator Puzzle

A lot of articles here at Digital Geography deal with maps and projections. You may have wondered how wrong the different map projections are or let’s say, what they lead us to think how big some areas on earth might be. Well, I can not tell you exactly, but the Mercator Puzzle gives you an idea on the errors that we need to deal with. Plus, it’s fun. Drag the outlines and fit them to countries: The Mercator Puzzle by Google. (To be honest, I expected myself to perform better…)

Vehicle tracking now also available for the trains of the German DB

I have to admit that I don’t know since when the Zugradar (train radar) of the Deutsche Bahn (DB) is online, but I found it per accident and I think it’s fun to play around with it. The DB commonly has a bad reputation because of the many delays, so here you can now see how many trains are actually moving and how fast they (sometimes) are. It’s possible to display long-distance trains (IC and ICE) as well as regional trains. Check out the high-speed train from Frankfurt Airport to Cologne, which goes with 300 km/h over almost the entire…

A great visualization of InSAR data by the ESA – ups and downs at the East African Rift

InSAR (Interferometric Synthetic Aperture Radar) is one of the greatest remote sensing tools for everyone interested in crustal movements. The principle is simple: A satellite equipped with a radar device is constantly measuring the topography of the Earth while orbiting. When it crosses the same area a second time, the two datasets can be compared and the changes in altitude can be measured. The fascinating thing is that these changes may be as small as < 1 cm, using the interferometric effect! Repeated measurements allow creating time series and monitoring areas with crustal deformation. Such deformation can be caused by…

Rainfall and weather data on GoogleEarth

On Saturday, some villages near my hometown suffered heavy rains. Up to 100 l/m² arrived during the afternoon and evening in Kirchhasel and other places in central Thuringia. Small streams became rivers and flash flooding occurred, damaging houses, roads, and cars. The local newspaper has an impressive pic dump. Locals say this have been the worst flooding for at least 40 years, so pretty much excitement here, we are not really used to this despite the river Saale caused some heavy floodings in the past. Now it looks like thunderstorms will arrive again: So I had a reason to think…

How to find geospatial data for Spain

In some countries, such as the USA and Spain, there is a very nice law that makes life easy for geoscientists. This law guarantees free access to a broad range of geospatial data like DEMs, satellite imagery, aerial photographs, ground use data, hydrological information and so on. In most cases, these data are made public via web-based GIS applications. These are generally rather slow, but allow to display a lot of different datasets. I did both my diploma thesis and my PhD in Spain and I really needed to find out about all the data available. I knew that they…