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The change of the rain factor on the net of stations in the Czech Republic during 1961-2010
Střeštík, Jaroslav ; Rožnovský, J. ; Štěpánek, P. ; Zahradníček, P.
Precipitation totals do not express precisely the humidity conditions in the landscape. Therefore the Lang’s rain factor, constructed from monthly and annual average temperatures and precipitation totals on 267 stations in the Czech Republic during 1961-2010, has been used here. Its values are very different at different stations, the lowest they are at South Moravia and Labe lowlands. Its average for the whole territory displays a slow decrease during the 50 years, supplemented by strong fluctuations. The strongest decrease appears in the Northern boundary mountains. The same factor calculated only for summer displays stronger differences between highlands and lowlands, especially in South Moravian ones. Stronger decrease at North Moravia, especially in mountains, and very weak decrease at other parts takes place.
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Increase of annual and seasonal air temperatures in the Czech Republic during 1961-2010
Střeštík, Jaroslav ; Rožnovský, J. ; Štěpánek, P. ; Zahradníček, P.
Using the monthly means of air temperatures at 267 stations in the Czech Republic, the long-term change has been estimated at each station for the last 50 years. Annual mean temperatures for the whole country show a considerable increase, more pronounced than that for global temperature, however, supplemented by strong fluctuations from year to year. Long-term changes in air temperatures at different stations and in different regions vary. Stronger increase in air temperatures can be seen in Bohemia, whereas in Moravia temperature increase is not so significant. This difference is more pronounced in the winter, whereas in the summer, the differences are smaller and perhaps of opposite nature. This means that the continentality of the climate in Moravia increases, while in Bohemia it very slightly decreases. Long-term changes depend only marginally on the absolute values of annual mean temperatures at the respective station. The increase of autumn temperatures is considerably lower than that of other seasons.
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The change of annual and seasonal precipitation totals in the Czech Republic during 1961-2012
Střeštík, Jaroslav ; Rožnovský, J. ; Štěpánek, P. ; Zahradníček, P.
Using the monthly values of precipitation totals at 267 stations in the Czech Republic a longterm change has been estimated at each station for the last 50 years. Annual totals for the whole country display a slight increase, however, supplemented by a much stronger fluctuations from year to year. Long-term changes in annual totals at different stations and in different regions are different. In southern and western Bohemia precipitation totals increased more, in Elbe lowlands and in a large part of the Moravia, rather a small decrease in rainfall has been observed. Long-term changes depend only slightly on the total rainfall at the respective station or in the region. Summer precipitation totals increased more than annual averages, while spring precipitation totals decreased, at other times seasons the change is negligible. At the same time, the annual variation changes slightly: maximum precipitation has shifted from June to July and August.
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Influence of precipitation and temperature in the period 1961–2100 on the possibilities to grow Picea abies in the Czech Republic
Cudlín, Pavel ; Štěpánek, P. ; Macků, J. ; Kohout, M. ; Rožnovský, J.
For environmental risk estimation of Norway spruce ecosystems under climate change, the space means for each „forest vegetation degree“ in the frame of all so called „natural forest areas“ basic climatic characteristics (above all mean daily diameter, daily precipitation sum) and two climatic extremes (number of days with daily precipitation sum < 1 mm, number of days with maximum temperature > 30 oC) were computed. Aggregate typological units, as“forest type sets” and “management types” in combination with “forest stand types”, were used for environmental risk estimation at „natural forest areas“ and whole Czech Republic levels. Endangered forest stands, occurred in given “forest type set”, „forest vegetation degree“ and „natural forest area“ were estimated using comparison of basic and derived climatic parameters between all 5 time period (1961–2099). Measured data from climatic stations were used for the period A (1961–1990) and B (1991–2009); for periods C (2010–2039), D (2040–2069) and E (2070–2099) the data were modeled by climatic model ALADIN-Climate/CZ. This procedure enabled to distinguish all „natural forest areas“ into “warm” ones, which do not meet requirements for ecological conditions of Norway spruce at present period B and “cold” ones which meet them
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