Desert Pavements: Assessing their Modulating Role in the Atmospheric Dust Cycle

• Applicants: Professor Dr. Alexander Brenning; Professorin Dr. Kerstin Schepanski
• Subject Area: Physical Geography
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 554051995

Desert pavements are global phenomena in arid environments and represent one of the most extensive geomorphological systems on Earth. In essence, desert pavements are a desert surface covered with densely packed clasts the size of pebbles or cobbles. Because of their surface-covering nature, desert pavements play an important role in current landscape dynamics, ultimately determining the interplay of key processes occurring at the surface–atmosphere interface. In particular, by covering desert surfaces and potential dust sources, desert pavements modulate dust emission by inhibiting wind erosion. Similarly, desert pavements affect the aerodynamic roughness length of the soil surface, which ultimately stimulates dust deposition on the surface. Thus, desert pavements are supposedly modulating dust emission and deposition fluxes, ultimately affecting regional atmospheric dust concentrations and dust aerosol associated feedbacks – a relevant theme in Earth system science due to its global repercussions for the nutrient and water cycles and radiation balance. Despite their abundance and strong links to key elements of the Earth system, the general understanding of the role of desert pavements in the Earth system in general and the atmospheric dust cycle in particular is still somewhat uncertain. In this research project, we will assess the spatial distribution and characteristics of desert pavements in Namibia and investigate their modulating role in the atmospheric dust cycle. We will combine machine learning approaches applied to remote-sensing and geomorphometric data with numerical modelling using an aerosol-atmosphere model. Overall, we expect this research to fundamentally change the way in which desert environments are represented in aerosol-atmosphere models through a suitable representation of desert pavements, and we anticipate that this will allow us to quantify and better understand the role of desert pavements in the atmospheric dust cycle.

• DFG Programme: Research Grants