Deposition patterns around buildings at the beach: Effects of building spacing and orientation

Cellular automaton modelling of the effects of buildings on aeolian bedform dynamics

“…At smaller building spacings, airflow and sediment transport through the gaps between buildings is limited, as wind and sand are predominantly diverted around the building group (Thiis and Jaedicke, 2000;Yen and Liu, 2011;Luo et al, 2014). As shown by the scale experiments at the beach (Poppema et al, 2022c), this creates downwind deposition tails at the outside of the building group that are larger than the deposition tails behind the gaps. If building spacing increases, wind and sand increasingly flow through the gaps instead of around the building group.…”

“…Different building configurations and wind directions are examined in these scenarios (Table 1). To study the effect of building geometry, different building sizes are tested, with building widths (perpendicular to the wind) of 4, 8 and 12 m, and building lengths and heights of 4 and 8 m. To study the effect of building spacing, the set-up of the field experiment (Poppema et al, 2022c) was implemented in the model. Triplets of buildings are placed in a row perpendicular to the wind and building spacing is varied per triplet.…”

“…Comparison of the effect of gap width on the downwind deposition pattern around rows of buildings in the field experiment (Poppema et al, 2022c) and in the CA model. experiment (Fig.…”

“…Existing studies on the morphological effects of buildings have focused on the local effects in a uniform flat environment, using scaled field experiments at the beach (Poppema et al, 2021;Poppema et al, 2022c) or in wind tunnel experiments (Iversen et al, 1990;Luo et al, 2012;McKenna Neuman et al, 2013;Luo et al, 2014;McKenna Neuman and Bédard, 2015;Luo et al, 2016). However, deserts and beach-dune systems are dynamic environments that exhibit strong bedform dynamics.…”

“…We develop new CA rules for the effects of buildings on local sediment transport. To test the performance of these rules, CA results of scenarios with buildings are compared to results of field experiments with individual scale models of various sizes (Poppema et al, 2021; data available as Poppema et al, 2022b) and scale model groups of various building spacings (Poppema et al, 2022c; data available as Poppema et al, 2022a). Longer-term model scenarios (up to decadal time scale) are used to explore interactions between self-organized bedform dynamics and building-induced deposition and erosion.…”