Pionowe gradienty temperatury powietrza w Sudetach

The paper presents the calculation of the vertical air temperature gradients for the free atmosphere within the mountainous area of the southern part of Poland (separately for the Carpathians and the Sudety Mts.) and the northern slope of the Karkonosze Mts., the highest part of the Sudety Mts. The gradients were determined on the basis of the analysis of the aerological diagrams with the least squares technique and the method of differential quotient between the air temperature values noted at the neighbouring weather stations. The average annual gradient of air temperature - irrespective of the method applied and the spatial scale - was equal 0.5°C/100 m of altitude. The gradients calculated feature the typical - for the moderate latitudes - annual course, with the lowest values in the cooler part of the year (0.4°C/100m), and the highest - in the months of the warmer half-year (0.6°C/100m). This is the result of the annual changes in the radiation balance: in the winter months the longwave out-radiation from the active surface dominates, leading to the decrease of the gradient values, white in the summer months the heating of the earth's surface dominates, entailing the increase of the air temperature differences in the vertical profile of the boundary layer of the atmosphere. Each of the methods of calculation of the vertical gradients of air temperatures gives the correct image of the directions and range of temperature changes corresponding to the increase of the altitude above the sea level. These methods, though, serve different purposes, since they define the properties of the thermal conditions existing in the free atmosphere (aerological gradients) and in the so-called mountain atmosphere. In the second case the geographical gradients define the features of the macroclimate, while the hypsometric ones - of the climate associated with the influence of the mesoforms of the surface relief. A comparison of the geographical or hypsometric gradients with the aerological ones gives the opportunity of developing the description of the influence exerted by the earth's surface on air temperature field observed in the free atmosphere.