Franco Miglietta

Franco Miglietta est directeur de recherche à l’Institut de Biométéorologie du Conseil National de la Recherche italien. Il s'intéresse depuis trente ans au changement climatique sous le prisme des questions de durabilité, d'adaptation, de mitigation et du rôle joué par la végétation terrestre. Il a coordonné plusieurs projets de recherche nationaux et européens sur ces questions, et collabore avec l'Agence spatiale européenne dans le cadre des missions spatiales Earth Explorer. Il a occupé des postes scientifiques de premier plan sur la scène mondiale et a écrit plus de 150 articles publiés dans des revues internationale.

Projet de recherche à l'IMéRA (en anglais)

Albedo-modifying properties of olive trees in Mediterranean climate: ecological, climate change and water savings implications.

Many Mediterranean schlerophyllous species have peculiar characteristics of their foliage. For instance native as well as cultivated species belonging to the Olea and Quercus genera have leaves that differ substantially in the optical properties of the upper (adaxial) and lower (abaxial) leaf surfaces. The upper surface is normally darker than the lower surface and this is mainly due to the presence of a dense hairy structure in the abaxial surface which reflects more light in the visible region. Under calm conditions (low wind and turbulence) the upper leaf side is exposed to sun while wind gusts that modify the architecture of the tree canopy often expose the lower leaf surface to incoming direct irradiance. As a consequence, windy conditions lead to an increase in the canopy albedo. Wind-driven changes in the spatial arrangement of the leaves can be responsible for a 0.02 change in albedo. Increased reflectance and, hence, reduced radiation absorbance can cause a detectable decrease in the upward longwave emission of the foliage