The researchers compared aerodynamic characteristics in different types of forests. They found that tree density affects how air moves through the forest, with denser stands having higher displacement. The roughness of the forest floor decreases with tree height. The amount of leaves in the forest also plays a role in how air flows through it. In cooler forests, the air movement changes with the seasons, especially when leaves fall in autumn. However, the models used to predict these changes underestimated the actual effects in the forests.