Predicted climate change may have negative impact on many environmental components including vegetation by increase of evapotranspiration and reduction of available water resources. Moreover, a growing global population and extensive use of water for irrigation and industry result in increasing demand for water. Facing these threats, quantitative and qualitative protection of water resources requires development of tools for drought assessment and prediction to support effective decision making and mitigate the impacts of droughts. Therefore, the Institute of Meteorology and Water Management, National Research Institute has developed and implemented a set of tools for the operational drought hazard assessment. The developed tools cover drought indices estimation, assessment of sensitivity to it formation and drought hazard prediction. They are streamlined into an operational scheme combined with data assimilation routines and products generation procedures.
A drought hazard assessment scheme was designed to be implemented into the platform of a hydrological system supporting the operational work of hydrological forecast offices. The scheme was launched to run operationally for the selected catchments of the Odra River and the Wisla River basins. The crucial resulting products are presented on the website operated by IMWM-NRI: POSUCH@ (Operational System for Providing Drought Prediction and Characteristics) (http://posucha.imgw.pl/). The paper presents the scheme and preliminary results obtained for the drought event which began in August 2011.
Drought is an extreme event that causes great economic and environmental damage. The main objective of this study is to evaluate sensitivity, characterization and propagation of drought in the Upper Blue Nile. Drought indices: standardized precipitation index (SPI) and the recently developed standardized reconnaissance drought index (RDIst) are applied for five weather stations from 1980 to 2015 to evaluate RDIst applicability in the Upper Blue Nile. From our analysis both SPI and RDIst applied for 3-, 6-, 12 month of time scales follow the same trend, but in some time steps the RDIst varies with small-er amplitude than SPI. The severity and longer duration of drought compared with others periods of meteorological drought is found in the years 1984, 2002, 2009, 2015 including five weather stations and entire Upper Blue Nile. For drought rela-tionships the correlation analysis is made across the time scales to evaluate the relationship between meteorological drought (SPI), soil moisture drought (SMI), and hydrological drought (SRI). We found that the correlation between three indices (SPI, SMI and SRI) at different time scales the 24-month time scale is dominant and are given by 0.82, 0.63 and 0.56.