Climate security assessment of countriesClimate security assessment of countries Peer-Reviewed Journal Publication Δημοσίευση σε Περιοδικό με Κριτές 2019-09-122018enClimate change has repercussions on national security. Yet, no widely accepted definition of climate security exists to date. In this paper, we present a mathematical model that defines and assesses climate security as a function of 37 indicators of exposure, sensitivity, and adaptive capacity. The model combines the indicators using statistical methods and fuzzy logic which encapsulates the subjective part of the assessment, to derive an overall climate security score from 0 to 1, and then rank 187 countries. A sensitivity analysis points to those indicators with the highest potential to improve climate security and indicates regional priorities for action. It turns out that globally the highest priorities are the economy which is necessary for climate adaptation, population growth which should be contained, political rights, renewable energy use, and sea level rise. Although several results such as the high ranks of Scandinavian countries are intuitive, the model uncovers unexpected facts such as the higher rank of Uruguay than Denmark and Japan or the higher rank of Costa Rica than Italy. However, a closer look at the intermediate results reveals that Uruguay and Costa Rica are far superior to Denmark, Japan, and Italy in the areas of water and energy.http://creativecommons.org/licenses/by/4.0/Climatic Change1481-225-43 Phillis Yannis Φιλλης Ιωαννης Chairetis Nektarios Χαιρετης Νεκταριος Grigoroudis Evaggelos Γρηγορουδης Ευαγγελος Kanellos Fotios Κανελλος Φωτιος Kouikoglou Vasilis Κουϊκογλου Βασιλης Springer Nature [academic journals on nature.com] Climate change Climate security Sensitivity analysis