#05 2023

Off to the USA for the 14th Annual Flux Course

By Amukelani Maluleke, PhD Candidate, EFTEON

After almost 30 hours of travel, I landed in Denver, Colorado just in time for the 14th Annual Flux Course, a prestigious two-week early-career workshop which focuses on the foundations of land-atmosphere flux measurement, modelling and synthesis. It is held annually at the University of Colorado Mountain Research Station at Niwot Ridge, northwest of Boulder, in an amazing subalpine forest located about 2 900 metres above sea level. 

About 27 course attendees from 18 countries were present, representing a host of institutions and universities predominantly from North America, followed by Europe, South America and Africa.

The course agenda was split into broad themes for each week, with activities run by instructors from AmeriFlux, the Integrated Carbon Observation System (ICOS), the National Ecological Observatory Network (NEON) as well as the National Center for Atmospheric Research (NCAR). Also in attendance there were technical representatives from LI-COR and Campbell Scientific.

The first week’s activities ranged from the theory of photosynthesis to gas exchange measurement across different scales. This focused primarily on the theory of eddy covariance (a micrometeorological technique to measure the continuous exchanges of CO2, latent and sensible heat between ecosystems and the atmosphere directly), which included the setting up of eddy covariance flux towers, learning about instrument capabilities, processing data and learning about the associated corrections performed in measuring ecosystem scale fluxes.

The second week had a particular focus on the “handshake” between measurements and models as well as integrating data from satellite observations. This included lectures, modelling and synthesis activities as well as group projects focusing on terrestrial biosphere modelling.

Niwot Ridge Flux Tower

Apart from the long hours spent in the Megaron (the main lecture room), there was also a fun hike up the mountain to about 3 000 metres above sea level to visit the Niwot Ridge Flux Tower, which has been in operation for 25 years. This 30-metre station measuring carbon and water fluxes in the subalpine forest is part of the AmeriFlux network and has surrounding heavily instrumented sites as part of the Long Term Ecological Research Network. Having been actively participating in the operation of two Expanded Freshwater and Terrestrial Earth Observation Network (EFTEON) flux towers at the Benfontein Nature Reserve during my PhD, this was a wonderful opportunity to exchange ideas about best practices and challenges in operating eddy covariance towers in completely different ecosystems.

As I am nearing the completion of my PhD, it was important to associate with other students from different global institutions and continue building a network of colleagues and friends who share similar interests. Importantly, being able to share a room with field experts such as Professor Dennis Baldocchi, Professor Dario Papale and Professor Marcy Litvak was a privilege for all the students as it promoted accessibility to knowledge as a continued necessity to build expertise in the field of eddy covariance. Their ability to turn complex materials into easily consumed bits is testament to their dedication.


I would like to thank the organisers, Professors Dave Moore and Kim Novick, for their selection of people from different backgrounds, gathering us all together for a memorable two weeks of learning and having us fall in love with ecology and measurements all over again. I would also like to thank SAEON and the National Research Foundation for their continued financial and student support in making this trip a possibility.

Niwot Ridge eddy covariance tower (Photo: Amukelani Maluleke)

Attendees of the 14th Annual Flux Course held in Denver, Colorado (Photo: Ngoc Nguyen)

Students during a lecture in the Megaron (with Amukelani in the bottom left corner) (Photo: Dave Moore)

Students setting up an open-path eddy covariance station (Photo: Amukelani Maluleke)

View from the top of the Niwot Ridge flux tower (Photo: Amukelani Maluleke)