Nowadays, in literature there are a lot of indices and factors designed to assess drought periods and water needs. Indices are presented in different spatial and temporal scale, from regional to global and chiefly are dedicated to agriculture and economy for making decision. Their application mainly depends on target and data availability. Such application imposes methodological approach; it means that obtained results should be comparable for different regions. Therefore drought indices are express as single number related to selected region. Some of them, especially the ones that are simple to calculate, are based only on one feature - precipitation for instance as a difference between total precipitation from investigated period and established norm from multiyear data. Others indices are based on more features as temperature, snow-cover, surface water and groundwater supply etc. Although it is hard to select a prori which index is the most effective, for each region the one that matches the best local environment and climatic conditions should be appointed. The paper presents a survey of indices for drought assessment and the results obtained for selected indices in Nysa Klodzka basin. ...
Preliminary Flood Risk Assessment (PFRA) aims at assessing the scale of flood risk for river basin areas. Furthermore, it focuses on identifying the risk of flooding in these areas. The areas subject to flood risk have been indentified on the basis of inventory works carried out at national, provincial and local level. The inventory covered information on the borders of flood hazard areas, hydrographic maps, spatial management plans and information on the condition of flood control structures. The inventory was based on questionnaires. The collected material was grouped and presented hierarchically depending on the type of flood. Then, it was reduced to a single frame of reference and a uniform scale. The gathered data is the basis for indicating sections of rivers for which flood hazards maps and flood risk maps will be developed. The Preliminary Flood Risk Assessment (PFRA) was developed under the project 'Global Monitoring for Environment and Security' (GMES). It is a part of the fulfillment of the obligations of Poland towards UE in implementing the first phase of Flood Directive. The paper presents the development of PFRA for the upper and middle Odra River. ...
