Termiczny okres wegetacyjny w Polsce - zróżnicowanie przestrzenne i zmienność czasowa

Spatial differentiation of mean dates of beginning and end and duration of thermal vegetative period as well as mean duration of it in Poland (years 1951-2000) is presented in this paper. Time-dependent characteristics of the growing season are analysed. Mean square deviations of average values of the characteristics of vegetative period in Poland (51 meteorological stations) were taken as indicators of dispersion of analysed sequences. There is essential linear trend showing that the vegetative period in years 1951-2000 trends to begin earlier in the course of the year. To an anomaly year 1990 is pointed out with abnormally early beginning of the growing season as well as long duration of it.