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The hydrologic cycle in Slovakia is determined mainly by three basic components: precipitation (P ), evapotranspiration (E) and runoff (R). The mean annual P total was 747 mm, E sum 476 mm and the mean R was 271 mm in Slovakia in 1951-1980 (E ≈ 0.65P and R ≈ 0.35P ). T increase in 1.6• C and annual P decrease in 24 mm (3.1%) were detected in the 1881-2007 period. Regimes of potential and actual evapotranspiration, soil moisture and R have been changed mainly in the southern Slovakia. A physical model for the estimation of the energy balance equation components (total radiation balance and its components, potential and actual evapotranspiration, sensible heat flux) has been developed. Input data are the air temperature and humidity, cloudiness, the number of days with snow cover and precipitation, all measured in the network of 31 meteorological stations in Slovakia since 1951. The 20-year period 1988-2007 was by 0.9• C warmer than the normal period mean. The observed increase is at the upper limit of all climate change scenarios projected for Slovakia in 1991-2001. Annual P totals have not changed significantly, but substantial changes have been found in the P regime. The scenarios show significant changes in the hydrological cycle not only at river basins balance but also in case of soil water balance, mainly in the southern Slovakia.

An extreme windstorm that took place on 7 December 1868 in the Czech Lands is analysed by means of rich documentary evidence from narrative sources, damage records, forestry journals and newspapers. Early meteorological measurements and a numerical atmospheric reanalysis support the documentary reconstruction. The windstorm reached hurricane‐force over the Czech Lands between 0900 and 1600 of local mean time and was related to the passage of a cold front. The high winds, achieving hurricane‐force, led to loss of human lives and many other casualties, as well as to severe damage to buildings and other structures. In particular, the documentary sources facilitate a quantitative reconstruction of the massive windthrow that occurred in forested areas across the Czech Lands, where the windstorm damaged at least 8 million m3 of timber, which is arguably more than has been lost to any single similar event since. Reasons for the extreme windthrow, apart from wind forces and destabilization arising from wet and thawed soils, were found in increased vulnerability arising out of old, dense and mono‐species conifer stands and inadequate clear‐cutting and thinning measures. For the Czech Lands, this event was the most damaging windstorm in the 19th century. Moreover, damage reports are found from the British Isles, the Netherlands, Belgium and Germany to Austria, the Czech Lands and Poland, documenting its disastrous effects on a (sub‐)continental scale.

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In this paper methods of climate-change scenario projection in Slovakia for the 21st century are outlined. Temperature and precipitation time series of the Hurbanovo Observatory in 1871-2007 (Slovak Hydrometeorological Institute) and data from four global GCMs (GISS 1998, CGCM1, CGCM2, HadCM3) are utilized for the design of climate change scenarios. Selected results of different climate change scenarios (based on different methods) for the region of Slovakia (up to 2100) are presented. The increase in annual mean temperature is about 3°C, though the results are ambiguous in the case of precipitation. These scenarios are required by users in impact studies, mainly from the hydrology, agriculture and forestry sectors.