The main objective of the CLIMHYDEX project is to improve our knowledge in understanding of complex mechanisms controlling the variability of the most important climate extremes and associated hydrological events in Romania at various time scales, through a comprehensive approach using advanced modelling techniques, a wide range of indices describing the climate extremes (more than 20) and high resolution data set. New high quality and high resolution climate data will be for the first time produced by integrating observed data from in-situ network with satellite and radar products using state-of- the- art tools (e. g. GIS techniques). This project offers, for the first time in Romania, an interdisciplinary approach on the analysis of climate and hydrological extremes.

CLIMHYDEX will address the major challenge in managing the climate change impact on hydrological extremes on basin scale by improving our knowledge of processes on small scale and subbasins, to find solutions for their quantification on one hand and to test the capacity of the hydrological models to represent the dominant processes in streamflow on the other hand. This is a new contribution in the CLIMHYDEX project, bringing results of experiments at small scale of representative basin to improve modelling and description of hydrological extreme indices and to provide adaptation measures.

Uncertainty associated to changes in climate extremes in Romanian for two future periods (2021-2050, 2071-2100) will be for the first time addressed in this project by projection of climate change scenarios under various IPCC emission scenarios derived from various state-of-the-art available global models (GCMs), using 4 types of statistical downscaling models (SDMs) developed in this project, combined with the values obtained directly from various regional climate models (RCMs). The uncertainties related to emission scenario, GCMs driving SDMs /RCMs as well as downscaling technique will be presented for the first time. The ENSEMBLES GCMs/RCMs will be used within the project. On hydrological basin scale, a novelty in this project refers to developing a conditional stochastic model on high spatial and temporal resolution.

To reach the proposed objectives, CLIMHYDEX brings together scientists from a wide range of expertise engaged in an interdisciplinary research. CLIMHYDEX has therefore assembled a consortium of three institutions with expertise in remote sensing, local meteorological and hydrological observations, climate and hydrological modelling, theoretical aspects of the climate systems and validation of global and regional climate models.