EGU25-16386, updated on 15 Mar 2025
https://doi.org/10.5194/egusphere-egu25-16386
EGU General Assembly 2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
Major distribution shifts are projected for key rangeland grasses under a high-emission scenario in East Africa at the end of the 21st century
Santos J. González-Rojí1,2,9, Martina Messmer1,2,10, Sandra Eckert3,4, Amor Torre-Marin Rando5, Mark Snethlage5, Kaspar Hurni3, Urs Beyerle6, Andreas Hemp7, Staline Kibet8, and Thomas F. Stocker1,2
Santos J. González-Rojí et al.
  • 1Climate and Environmental Physics, University of Bern, Sidlerstrasse 5, Bern, 3012, Bern, Switzerland.
  • 2Oeschger Centre for Climate Change Research, University of Bern, Sidlerstrasse 5, Bern, 3012, Bern, Switzerland.
  • 3Centre for Development and Environment, University of Bern, Mittelstrasse 43, Bern, 3012, Bern, Switzerland.
  • 4Department of Geography, University of Bern, Hallerstrasse 12, Bern, 3012, Bern, Switzerland.
  • 5Institute of Plant Sciences, University of Bern, Altenbergrain 21, Bern, 3012, Bern, Switzerland.
  • 6Institute for Atmospheric and Climate Science, ETH Zurich, Universitätstrasse 16, Zurich, 8092, Zurich, Switzerland.
  • 7Department of Plant Systematics, University of Bayreuth, Universitätsstrasse 30, 95440 Bayreuth, Germany.
  • 8Land Resource Management and Agricultural Technology Department, College of Agriculture and Veterinary Sciences, University of Nairobi, P.O Box 29053-00625, Nairobi, Kenya.
  • 9Present address: Department of Physics, University of the Basque Country, Barrio Sarriena s/n, 48940, Leioa, Spain.
  • 10Present address: Geoscience and Remote Sensing, Faculty of Civil Engineering and Geosciences, Delft University of Technology, Stevinweg 1, 2628 CN, Delft, The Netherlands.

Grassland landscapes are important ecosystems in East Africa, providing habitat and grazing grounds for wildlife and livestock and supporting pastoralism, an essential part of the agricultural sector. Since future grassland availability directly affects the future mobility needs of pastoralists and wildlife, we aim to model changes in the distribution of key grassland species under climate change. We combine a global and regional climate model with a machine learning-based species distribution model to understand the impact of regional climate change on different key grass species. The application of a dynamical downscaling step allows us to capture the fine-scale effects of the region’s complex climate, its variability and future changes.

Under present-day climate conditions, the arid lowlands of eastern and northern Kenya seem favourable to all studied grassland species. However, future climate change under the high-emission scenario RCP8.5 is expected to alter the distribution and composition of grassland ecosystems. While C. ciliaris and D. milanjiana, show a slight overall increase in habitat suitability, species such as C. dactylon, C. plectostachyus and C. mezianus are projected to experience notable range contractions. The Turkana region, in particular, is expected to be severely impacted, with a near-complete absence of the studied species under the high-emission scenario. These negative effects are likely driven by increased precipitation and seasonal temperature, which create unfavourable conditions for many grass species. Elevated regions present less favourable conditions for some of the considered species under present-day climate conditions. However, the projected higher temperatures will possibly help some of the grasses to conquer these regions. With this study we tried to anticipate the currently still uncertain changes in grass species, key for wildlife and livestock of pastoralists, under climate change. Our results are valuable for assessing the economic potential of the region and the sustainable long-term planning, for example when designing livestock and wildlife corridors or highway crossings.

How to cite: González-Rojí, S. J., Messmer, M., Eckert, S., Torre-Marin Rando, A., Snethlage, M., Hurni, K., Beyerle, U., Hemp, A., Kibet, S., and Stocker, T. F.: Major distribution shifts are projected for key rangeland grasses under a high-emission scenario in East Africa at the end of the 21st century, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-16386, https://doi.org/10.5194/egusphere-egu25-16386, 2025.