Soil shrinks as it desiccates, and the magnitude of shrinkage can be large for clayey
soils. The drying of soil leads to cracks formation, causing high suctions to develop within.
Cracks expose the deep soil and more evaporation can be expected in dry periods. To illustrate
the effect of cracking, a numerical model of soil-atmosphere interaction has been developed
taking into account the thermo-fluid coupling of an unsaturated clay soil. The model is used to
simulate the evolution of evaporation during the drying process. The main results show a
significant influence of the presence of cracks on the evaporation. This study also offers a simple
method for taking into account the presence of cracks in the soil-atmosphere exchange
