Project Pressure Rwenzori Expedition maps Uganda’s disappearing tropical glaciers

The Rwenzori mountains have three main peaks, Mt. Stanley, Mt. Baker and Mt. Speke. The ice on Rwenzori is the highest and most permanent source of the River Nile and constitutes significant water catchment areas in Uganda—relied upon by five million people.

The Project Pressure team confirmed that the glaciers on Mt. Baker and Mt. Speke have now disappeared. The highest peak, the top of Mt. Stanley reaches 5,109 metres (16,762 ft), and the upper regions are still glaciated, but the ice is melting at alarming rates and will likely disappear in our lifetime.

To learn more, the team led by Klaus Thymann used Trimble geospatial technologies to create the first 3D model of the last remaining glacier on the Stanley Plateau. In particular, the small, lightweight, and easy-to-use Trimble Catalyst GNSS positioning service was key to success. GNSS accesses multiple satellite systems to deliver high-precision points—essential for this complex environment. With the technologies provided by Trimble, precise geolocation points were installed and data was captured at multiple sites—providing the foundational data that underpins the entire 3D photogrammetry model.

This solution was critical in anchoring the high-resolution drone imagery to exact coordinates. Over several days, more than 850 images were captured, including all geolocation points, ensuring the model’s spatial accuracy. Despite challenging mountain conditions, the data collection was successful with support from Solomon Kule and Muhindo Rogers. These are the first high-precision 3D glacier models in the region. To deepen the research, Dr. Heïdi Sevestre conducted ground-penetrating radar surveys of the ice and bedrock—also a first here—with analysis led by Andrea Blindenbacher’s team in Switzerland.

For the Rwenzori’s Bakonzo people, loss of the ice has enormous cultural implications. The Bakonzo hold deep spiritual beliefs that are intricately connected to the natural landscape, particularly the snow-capped peaks. A central belief is that their gods, Kithasamba and Nyabibuya, reside in the ice of Rwenzori. For centuries, this spiritual connection has influenced how the Bakonzo interact with their environment, reinforcing conservation efforts and sustainable use of natural resources, long before colonial or modern times.

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