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Updated: May 27, 2026
13:27
Exploring the Effects of Atmospheric Forcings on Evaporation: Experimental Integration of the Atmospheric Boundary Layer and Shallow Subsurface
Published on: June 8, 2015
Effects on evaporation rates from different water-permeable pavement designs
P Starke1, P Göbel, W G Coldewey
1Department of Applied Geology, University of Münster, Corrensstrasse 24, 48149 Münster, Germany.
Summary
Water-permeable pavements (WPPs) improve urban climate through increased evaporation. While sub-base layers and color impact evaporation, grass pavers significantly boost evapotranspiration more than pervious concrete.
Area of Science:
- Environmental Science
- Urban Planning
- Civil Engineering
Background:
- Urbanization alters natural water balance and increases heat island effect.
- Water-permeable pavements (WPPs) offer a sustainable solution for stormwater management and urban climate mitigation.
- Evaporation from pavements significantly influences the urban thermal environment.
Purpose of the Study:
- To investigate the impact of different WPP designs on evaporation rates.
- To identify factors influencing pavement evaporation for improved urban climate regulation.
- To compare the evaporative performance of various WPP materials and structures.
Main Methods:
- Comparative evaporation measurements of different WPP designs.
- Analysis of sub-base composition (grain size, twin-layer vs. homogeneous).
- Evaluation of surface properties (color) and vegetation integration (grass pavers).
Main Results:
- Sub-base grain size had no significant effect on evaporation rates.
- A twin-layer sub-base reduced evaporation by 16% compared to a homogeneous one.
- Changing paving stone color increased evaporation by 19%.
- Grass pavers demonstrated over threefold higher evapotranspiration rates than pervious concrete.
Conclusions:
- WPPs enhance urban climate through increased evaporation, with design choices significantly impacting performance.
- While pervious concrete offers broad applicability, grass pavers provide superior evapotranspiration benefits.
- Optimizing WPP design, considering factors like color and vegetation, is crucial for effective urban climate mitigation.
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