About Me

Let me introduce myself

That's me!

I am a PhD student in physical oceanography at Niels Bohr Institute, Copenhagen. Although I have been doing geophysics for a while now, I mostly see myself as a “computer guy”. I have a passion for scientific software, modeling, statistics / machine learning, and effective communication / visualization. I live in Malmö, Sweden.

At NBI, I am also responsible for the development of Veros, a high-performance ocean model with a special focus on usability.

My personal interests cover a wide range between Coding and Technology, Science, Art and Design, and Pop Culture (and so does my blog). I am a huge fan of the scientific Python ecosystem, and love experimenting with great libraries such as Numba, Dask, xarray, or scikit-learn.

Code Projects


The versatile ocean simulator: a full-blown, high performance ocean circulation model in pure Python. Fully parallelized on CPU and GPU through coupling to Bohrium - without compromising on accessibility. Developed at Niels Bohr Institute (Copenhagen University). View on GitHub.


An open source package for simulations of animal species based on a model proposed by Botero et al., 2015. View on GitHub.


A numerical solver for the Richards equation (soil water flow in unsaturated media), based on the DUNE framework, and developed at the Institute of Environmental Phyics (Heidelberg University). More information.

Enhanced Botero Model

An open source package for simulations of animal species based on a model proposed by Botero et al., 2015. View on GitHub.

This homepage

This homepage (including the blog) is entirely static (created using Pelican) and hosted on GitHub Pages. My theme is based on molivier‘s “Nest”, but is heavily altered to fit my needs.

If you like, you can have a look at the sources at GitHub. Everything you see here is open-source, so feel free to use it for your own project!




  • Häfner, Dion, et al. “Veros v0.1–a fast and versatile ocean simulator in pure Python.” Geoscientific Model Development 11.8 (2018): 3299-3312. Available online.


  • Veros–High-performance earth system modelling in pure Python” @ EGU General Assembly 2019 in Vienna, Austria. Slides available online.
  • Veros—A High-Performance Ocean Simulator Written in Pure Python” @ AMS 98th annual meeting in Austin, Texas. Abstract and slides available.

My Master's thesis

Master’s thesis

During my Master’s thesis in Physical Oceanography at NBI Copenhagen, I ran ocean simulations using the CESM climate model. I examined the dependence of cross-equatorial flow and the meridional overturning circulation (MOC) on viscosity close to the western ocean boundaries. My work at NBI was an interesting mixture of modeling, data evaluation, and theory.

My finished thesis, along with the LaTeX sources, can be found on GitHub.


Everything else…



I am a huge sucker for indie music. While you’re here, why don’t check out one of my playlists?