Detail of plowed soil in a field – illustrative photo.
Větrný Jeníkov (Jihlavsko) – Climate change in the last 20 years has fundamentally changed the shape of agricultural areas in the Czech Republic. The trend has not stopped and is set to continue, which is why the areas will be transformed by the year 2050. Maps in geography textbooks from the turn of the century are not valid today, and the current maps will not be valid in the next 20 years either. Due to the increase in average temperatures and the extension of the growing season, potato, fodder and grain growing areas are disappearing from the Czech Republic, said Zdeněk Žalud, a bioclimatologist from the Global Change Research Institute of the Academy of Sciences of the Czech Republic, at a meeting of the creators and users of the Intersucho project today.
When comparing the conditions from 1961 to 2000 and from 2001 to 2020, it is obvious that the maize and beet growing areas, typical of warmer regions, have significantly expanded, and the conditions have enabled the creation of the vineyard area. The formerly cooler Bohemian-Moravian Highlands gradually became a warmer area, where it is increasingly advantageous to grow crops that thrived mainly in South Moravia or Polabí in the last century. The once most fertile areas of the Czech Republic are drying up, and if there is not enough rain in them, yields are often lower than in the Highlands.
“Last year's average temperature of 9.2 degrees fits right into a trend that's been evident since the 1960s,” Žalud said. Since then, it's been warming decade after decade, with the second decade of the century warming even faster than the previous. In 60 years, the average temperature has increased by 2.2 degrees. On the other hand, the annual average precipitation has not changed significantly, which does not mean that the water in the landscape is the same. “Colleagues calculated that the increase in temperatures means that 100 millimeters more water than before,” said Žalud. Areas that have been affected by drought before are thus even more threatened by drought.
However, compared to the past, water is not missing only because of evaporation. Taking a closer look, meteorologist and climatologist Pavel Zahradníček from the same institution found that, statistically, precipitation significantly decreases in April to June and, on the contrary, increases in July to September. Which is a problem for agriculture, because water can be absent in the spring and, on the contrary, remains in the summer, when it is not needed as much during the harvest. “Moreover, there are often intense to extreme rainfalls in the summer, which quickly drain away from the landscape,” said Zahradníček. The long-term trend is also a decrease in snowfall, more rain in winter, which further reduces the water supply for the start of vegetation in spring.
The number of days in the growing season when the soil is dry increases more and more. “As long as it was 15 days a year, it was tolerable and normal, but when there are 50, you need to adapt to it,” said Zahradníček.