TopoToolbox documentation integrated in MATLAB help browser

Posted on Updated on

TopoToolbox version 2.3 will have a better documentation. With the latest commits to our github repository, you are now able to take a glance at our work-in-progress. Just download it, follow the instruction in the readme file, and then type


in the command window. MATLAB’s documentation browser will pop up and the landing page will have a new entry in the section Supplemental Software. The link will bring you to the TopoToolbox documentation.

The MATLAB documentation landing page

The documentation features a Getting Started section, numerous guides, and a function reference (which is, however, not linking to the individual help functions).

The TopoToolbox documentation

Moreover, you can now search the documentation which will hopefully make it much easier to find the right tools.

Search the documentation for the term ‘ksn’.

The documentation is not yet complete. We are still working on including the help sections of each function into the documentation, which will make the functionality even more accessible and browsable.

**** addendum January 15, 2018 ****

After permanently setting the paths, you might need to restart MATLAB in order to be able to view the documentation in the help browser.


4th Summer School funded by the Volkswagen Foundation, Deadline 1 October 2017

Posted on Updated on

This post is written by Martin Trauth who is a professor for paleoclimate dynamics at the University of Potsdam. Consider applying for this summer school. Deadline is soon! It will be a great opportunity to learn a lot in short time and to expand your network. Please find all information below.

We are pleased to announce two fully sponsored consecutive summer school sessions on “Earth Surface Dynamics Understanding Processes at the Earth’s Vulnerable Skin” for 25 doctoral students from geosciences, environmental sciences and related fields such as biology, chemistry and physics. These summer schools funded by the VolkswagenFoundation will be designed for doctoral students, aiming (1) to improve their skills to understand the complex interaction of the processes shaping the Earth’s surface at different temporal and spatial scales, (2) to monitor, model and predict the results of these interactions, and (3) to identify and mitigate risks of natural and human-caused interference in these processes in an interdisciplinary and intercultural environment. The two summer schools each comprise three modules with each module covering a week, taking place at different locations in Germany (Rügen Island, Wandlitz, 2x Potsdam, Neustadt an der Weinstrasse, Garmisch-Partenkirchen/Zugspitze). These locations are representative of typical settings for Earth surface processes, from the coast to lowlands and from continental rifts to high mountains. The FIRST SET OF MODULES will focus on types of signals and noise commonly encountered at the Earth’s surface, and methods of acquiring, processing and analyzing data with non-destructive physical surveying methods. The SECOND SET OF MODULES will be about the examination and modeling of the processes underlying the data collected at the Earth’s surface.

The summer school fellowship covers all costs for transportation, accommodation and meals during the summer school. Full or partial support for travel expenses to/from Potsdam will be granted according to necessity. The fellowship does not cover, though these things are necessary for participation, costs for (1) a computer laptop, (2) hiking boots and clothing, and (3) insurance and medical costs. No daily allowance will be paid.

The intense, multifaceted science training program of the summer school will help participants to acquire knowledge and understanding of the processes shaping the Earth’s vulnerable skin and to define premier research topics to study processes at the Earth’s dynamic surface. Participants in the summer school are expected to form part of a new generation of researchers, practitioners and lecturers with the necessary background and scientific tools to evaluate and mitigate the effects of present-day and future environmental change.

More information and how to apply can be viewed here. There is also a summer school flyer. Please feel free to forward this message to interested people. Please send your questions about the summer school to esd2018@geo.uni-potsdam.de.

Kind regards, Martin

Steepness derived from smoothed river profiles

Posted on

Today, I gave a talk in the weekly seminar of Manfred Strecker’s group at our institute. The talk had the title: Introduction to TopoToolbox and its application in tectonic geomorphology. Among other, I provided an example of how to calculate and plot the steepness of river networks (see the new function ksn) and how the new smoothing function crs (Schwanghart and Scherler 2017) is helpful here. I am providing the code here for the DEM of the Big Tujunga catchment, but you can easily adapt the code to your own needs.

First, load the DEM and derive flow directions and the stream network. In addition, calculate a flow accumulation grid that we need for calculating ksn.

DEM = GRIDobj('srtm_bigtujunga30m_utm11.tif');
FD = FLOWobj(DEM,'preprocess','carve');
A = flowacc(FD);

We then extract the stream network for a threshold upstream area of 1 sqkm.

S = STREAMobj(FD,'minarea',1e6,'unit','map');
S = klargestconncomps(S,1);

To hydrologically correct and smooth the river profile, we use the function crs:

zs = crs(S,DEM,'K',6,'tau',0.1);

And finally, we plot it all

imageschs(DEM,[],'colormap',[1 1 1],'colorbar',false,'ticklabels','nice');
hold on
hx = colorbar;
hx.Label.String = 'k_{sn}';
Map of ksn values in the Big Tujunga catchment.

Which parameter values should be used to smooth the stream profile? The values depend on the amount of scatter in the profiles, their spatial resolution, and the amount of smoothing. Visual cross-checking of the results is thus advisable. In this lecture, I presented the tool crsapp that let’s you identify a suitable set of parameter values. A screenshot of the tool can be seen below.

The crsapp GUI let’s you interactively choose the right parameters for smoothing river profiles.


Schwanghart, W., Scherler, D., 2017. Bumps in river profiles: the good, the bad, and the ugly. Earth Surface Dynamics Discussions 1–30. [DOI: 10.5194/esurf-2017-50]

Summer School 2018 on Earth Surface Dynamics

Posted on

The VolkswagenFoundation funds a series of two summer schools entitled “Earth Surface Dynamics – Understanding Processes at the Earth’s Vulnerable Skin” led by apl. Prof. Dr. Martin H. Trauth, together with nine instructors from Germany, United Kingdom, and Ethiopia. The application is now open, and the deadline is 1 October 2017. Download the summer school 2018 flyer.

Here is the program:

Please find additional information on location and time of the summer school and on how to apply on Martin’s blog:

Hope to see you there!

Best regards, Wolfgang


Finishing course on high resolution topography

Posted on Updated on

DCOPlAIUQAAao8J.jpg large
TopoToolbox magic is just a system of linear equations…

Today was the last day of the Strategy course ‘Advancing understanding of geomorphology with topographic analysis emphasizing high resolution topography‘ that more than 20 international students and researchers attended. Ramon Arrowsmith (Arizona State University), Bodo Bookhagen (University of Potsdam), Chris Crosby (UNAVCO) and I provided guidance to the analysis of digital elevation models. Obtaining fluency in writing MATLAB- and TopoToolbox-code was among the major aims of the course. The enthusiasm and steep learning curve of the participants demonstrate that we probably reached this goal. Thanks to all participants and colleagues that this course was such a success!

For those who were unable to attend: Here is the link to the course website on opentopography.org that hosts a number of slides and code snippets.


New Master’s Degree Program at the University of Potsdam

Posted on

The University of Potsdam has a new Master’s degree program “Remote Sensing, geoInformation and Visualization”. This English-language program focuses on the gathering, processing, analysing, and presentation of geoscientific spatial data by using remote-sensing technologies and data-processing methods. The program uses models and theories to assess geoinformation, and then to prepare and communicate our findings with modern means of visualization.

The new program provides a great opportunity to improve your skills in a rapidly evolving research field that also has broad applicability outside academia. If you are interested, please see this site here for further details on the program and the application for enrollment. See you in Potsdam!

Geomorphometry Short Course at the EGU 2017, Vienna

Posted on


Only few days left until the EGU begins, the largest European annual geoscience meeting in Vienna. In case you attend you should consider to participate the short course in geomorphometry: Getting the most out of DEMs of Difference. The course is organized by Tobias Heckmann, Paolo Tarolli and me and will be on Wednesday, 26 April, 13:30-15:00 in Room N1.

Please see here for further details on the course’s aims and scope.