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Content available Termiczne pory roku w Hornsundzie (SW Spitsbergen)
In the studies on climate and its changes in the polar regions it is essential to determine climatic seasons which can be based on thermal, circular and phenological criteria but also according to different types of weather. The aim of this research is to determine thermal seasons, to characterize their structure and general regularities, which may make the more detailed environmental monitoring of these areas possible. According to many authors, a climatic characterization of a given area should be presented through defining its seasonal structure. This article attempts to find natural thermal periods in the polar climate, which differ from the conventional, fixed monthly or quarterly periods: spring III-V, summer VI-VIII, autumn IX-XI, winter XII-II; often accepted by many scientists in order to make the characterization of the course of selected meteorological elements easier. The analysis of the seasonal structure of the climate of Hornsund is based on the data from the period of 1990-1999. The indices that characterize the initial and final dates, the overall duration of the thermal seasons, and estimation of the seasons? changeability in thermal terms have been taken into consideration. Calendar boundaries have been set according to the method proposed by Kosiba (1958), in which the date that begins the period of the domination of days with the daily average air temperature (Ti) typical for a given season is accepted as the season?s boundary. As the quite significant changeability of the daily average air temperature complicates the choice of initial and final dates of seasons, additional criteria are used: the number of days proper for thermal season (w), days warmer than w?days, days colder than w-days, the average air temperature and other. This study provides a division into four seasons according to Baranowski?s criteria (1986) accepted on the basis of an analysis of the annual course of air temperature in Hornsund, the accepted thermal criteria are as follows: spring -2.5°C <= Ti <= 2.5°C, summer Ti >= 2.5°C, autumn -2,5°C <= Ti <= 2.5°C, winter Ti <= -2,5°C. The characteristics of a vegetative period are also defined. Its duration in the polar regions is difficult to estimate. If we accept the most commonly used criterion of the stabilization of the daily average air temperature over +5°C, we will face the situation in which the vegetative period in the polar regions is either very short or does not occur at all. Phenological observations of Sorkappland - S Spitsbergen (Dubiel, 1988) made it possible to estimate a natural thermal threshold 0?C which begins the vegetative period. The development of most plants and their first flower buds occurs in average air temperature of approximately 0?C. Blooming and producing seeds, on the other hand, occur when the air temperature exceeds 2.5°C. Seasons (fig. 17), determined on the basis of daily average air temperatures, characterize and emphasize the changeability of thermal conditions and the specifics of the polar climate very well, what results in the conclusions enumerated below: - in the researched decade the initial and final dates and the overall duration of the thermal seasons are characterized by great changeability, - the most stable, with regard to the initial date, are spring and summer, - the most changeable, with regard to duration, are autumn and summer, - the most thermally stable season is summer. The least thermally stable season is autumn, - transitional seasons have a tendency to prolong: mainly autumn (the effect is that winter becomes shorter) and to a lesser extent spring. Winter and summer shorten, - the analysis of the line of this trend reveals that summer gets slightly colder. Spring and winter do not show any significant changes, - the most visible tendency is a downward tendency of autumn temperatures - the effect of the prolonged duration towards winter, - a vegetative period shows a tendency to begin later and to finish slightly earlier. The final date, however, does not reveal any significant tendency for changes.
W artykule dokonano podziału maszyn ze względu na ich sezonowe wykorzystanie. Opisano ich rodzaje wraz z zakresem wykonywanych nimi czynności.
Content available Pory roku Petara Alipieva
The seasons of Peter Alipiev Peter Alipiev is a fine example of the poetic emblems of the 1960s. Man and nature translate and express themselves. The poetic world of P. Alipiev is unified, round, fundamental. The four seasons, each of them magical, concern a great number of his texts. Different aspects and transformations of life are captured through the use of various seasons. However, human nature is expressed in a wide spectre of emotional states and philosophical thought. The most important season for Alipievs sensitivity is autumn. Nature in P. Alipievs poetry is seen through human eyes. Pictures of nature express existential wisdom. This poetry is quiet and still. There is sorrow, but also thirst for life – of man and bird, of old man and grass, of child and bee. Key words: Petar Alipiev; poetry; sesons; Bulgarian literature;
Content available remote Sposoby wydzielania pór roku
This paper tries to classify in detail the ways of defining seasons. The seasons, most generally can be divided into: astronomic, climatologic, meteorologic, phonologic and within subgroups: meteo-rologic with calendar, thermic with aeroclimatic, bioclimatic and synoptical within the climatologic group, as well as fito- and zoophenological within the phonological group. The oldest divisions of the year onto particular seasons had their root in the changes of the Earth's location in relation to the Sun. Until now, the division into astronomical season has been very common. In meteorology and climatology it may seem more proper to adopt the division into four seasons and to define their limits as three full months, i.e. quarters (meteorological seasons). Unfortunately in detailed clima-tological analyses, it is not enough to divide the year into four equal periods, especially in Polish climate, due to its locations on the boundary of collisions of continental and oceanic air masses. In this climate, a good way is to fix the dates of the commencement and the end of particular periods on the basis of different meteorological elements, e.g. air temperature (thermic seasons), atmos-pherical circulation (circulation or synoptical seasons) or the whole mixture (climatologic seasons).
The aim of the present paper is to analyse thermal conditions at the Zawady Experimental Farm (EF). The work utilises the results of measurements of average 24-hour air temperature from 2002–2006 obtained from an automatic meteorological station (geographical location: Hs – 150 m, φ – 52.06N, λ – 22.56E) situated in the Zawady EF. On the basis of the results of observations an average monthly air temperature as well as average yearly air temperature were calculated, the values and dates of an occurrence of minimum and maximum 24- -hour air temperatures were determined, the length, beginning and end of meteorological growing seasons were determined, and the number of days in the temperature ranges of the winter and summer period were calculated. The average yearly air temperature at the Zawady EF ranged from 7.9oC (2004) to 8.9oC (2002).
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