Implementing Crop Evapotranspiration in RDI for Farm-Level Drought Evaluation and Adaptation under Climate Change Conditions

Agricultural drought is a natural hazard, often leading to significant crop yield losses and jeopardising food security. Climate change is anticipated to increase the duration and the magnitude of drought events, augmenting also their adverse effects. Recent studies, as well as policy initiatives, emphasise the need of proper farm-level management, for efficient mitigation of drought effects and adaptation to climate change. Towards this objective, robust, practical and comprehensible tools should be employed to support decision making process. In this paper, the Crop Reconnaissance Drought Index (CRDI) is introduced, aiming at assisting in agricultural drought analyses, focusing on specific crops. The proposed CRDI is an adjustment of the widely used Reconnaissance Drought Index (RDI), in which the utilised parameter of reference evapotranspiration is replaced by crop evapotranspiration. Along with this amendment, other issues regarding the calculation of CRDI are discussed, such as the selection of appropriate reference periods and methods of crop evapotranspiration assessment. The significance and the advantages of CRDI are illustrated through an application, considering different crops under Mediterranean conditions, in three regions of Greece.