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The objective of this paper is to present time and space analysis of drought occurrence in the agricultural regions in Slovakia. It considers the most important natural environment factors influencing the occurrence, duration and intensity of this phenomenon. The analysis of the occurrence of meteorological and agronomic drought was performed for the period 1961 - 2014. The results detect the importance of dealing with the problem of drought in Slovakia. Drought occurred every year during investigated period except in 1965 and 2010 at least in a part of Slovakia. The performed analyses identify the increased intensity of drought. The paper compares two approaches to drought identification. From the results obtained it could be evaluated, that there exist various limitations, when drought (especially agricultural drought) is evaluated using climatic indices (Standard Precipitation Index was used in this paper) and much more comprehensive results were gained using the DAISY agro-ecological model, which also considers soil properties and the water requirements of plants. [ABSTRACT FROM AUTHOR]

The significant increase of precipitation in Slovakia after the long dry period 1981-1994 has a direct relation to the incidence of floods after 1996. Over the past 10 years (2000-2010), the amount of precipitation in Slovakia was by almost 150 mm higher than in 1981-1990. The year 2010 was the wettest one during the last century. The aim of this paper is to briefly summarize the historical floods that occurred in Slovakia. The systematic instrumented hydrological observations were initiated mostly in the second half of the 20th century. The available relatively short time series of water stages or discharge can provide an insight into neither extreme floods with long return periods, nor the significant changes in their frequency and changes in the intra-annual distribution of runoff. Such information may be of importance for risk assessment of both - floods and droughts. Therefore, it is necessary to reach for other data sources as well. The evaluation of the design values (N-year flood) from the series of annual discharge maxima from the instrumented era resulted in an underestimation of the flood risk. Data on floods before the instrumented era can be obtained by analyzing related natural data - so called paleofloods, or various documents and historical sources (flood signs, annals of the cities and villages) - so called historical floods. From our analysis confirms that the flood of 1813 was one of the most significant floods on the territory of Slovakia over the past 250 years. [ABSTRACT FROM AUTHOR]

Droughts rank first among all natural hazards when measured in terms of the number of people affected. Drought is the most complex but least understood of all natural hazards. It is broadly defined as "severe water shortage". Northern Africa is one of the most arid areas of the world, with rainfalls that vary widely in terms of both temporal and geographical distribution. Libya just like most parts of North Africa is facing drought. Statistical analysis for time series can reveal possible trends in time. For drought risk analysis it is very important to study the historical climate parameters (temperature and precipitation) to know if there is a trend, downward or upward. The aim of this paper is an investigation of the trends by using statistical methods, exactly non-parametric Mann-Kendall test, in these parameters because they have a strong correlation and are related with drought. [ABSTRACT FROM AUTHOR]

Droughts rank first among all natural hazards when measured in terms of the number of people affected. Northern Africa is one of the most arid areas of the world, with rainfalls that vary widely in terms of both temporal and geographical distribution. Libya just like most parts of North Africa is facing drought. Statistical analysis for time series can reveal possible trends in time. For drought risk analysis it is very important to study the historical climate parameters (temperature and precipitation) to know if there is a trend, downward or upward. The aim of this paper is an investigation of the trends by using statistical methods, exactly non-parametric Mann-Kendall test, in these parameters because they have a strong correlation and are related with drought. [ABSTRACT FROM AUTHOR]

Daily precipitation data measured in 38 meteorological stations during all months of the year in the period (1960 - 2009) are sorted looking for consecutive days with precipitation. The used 38 points are approximately uniformly located on the territory of the country (19 in North Bulgaria and 19 in South Bulgaria) and represent in fact the basic (synoptic) stations in the meteorological network of the National Institute of Meteorology and Hydrology. Fifteen cases of extreme number of consecutive days with precipitation (>15 days) are revealed on the territory of the country during the examined 50-years period. These cases represent exceptionally rare events with a great return period and form a relatively small but obtained through a sort of an enormous volume of data sample that is a good basis for an interesting and significant analysis of the examined rare phenomenon. The obtained results concerning the distribution of the revealed extreme cases over territory, during the years, by seasons and months, and according to the precipitation type amount are summarized in the paper together with the common features of the corresponding synoptic situations. The proposed investigation is a part of a greater research aiming to reveal the spatial - temporary regime of the number of consecutive days with precipitation over Bulgaria and the corresponding typical synoptic situations together with the eventual climatic variations of this regime and their relation to the drought events in the country. [ABSTRACT FROM AUTHOR]