Vízrajzi Évkönyv 78., 1973 (Budapest, 1975)
Tartalomjegyzék
В. OBSERVATION DATA AND THEIR PROCESSING. I. Hydrometeorological and hydrological characterization of the year. In this chapter, annual and seasonal patterns of precipitation and air temperature, supplemented by data relating to the irrigation halfyear are described. A general picture on sunshine duration and on evaporation conditions is given too. This description is supplemented by the charts, figures and tables pointed in Chapter IV. In addition, there is a summary of the surface and subsurface water regime, the ice and shallows conditions, comparing these informations to normal and extreme values. Concerning ice conditions, comparative data are published only for the Danube and the Tisza. Condensed data of excess water inundations are given too. II. Surface waters. 1-2. / When publishing gauge readings, Chapter 1. contains daily mean water stages on a member of the principal gauging stations, whilst in Chapter 2, a review of the characteristic water stages is given. Within both chapters, gauging stations are listed according to the natural order of the hydrographi - cal system, that is, proceeding in a downstream direction. The data of gauging stations were tabulated by computer process. Stages influenced by ice are separately marked. In the heading of each tables, there were included, for convenience, the altitude of the gauge zero and the extension of the catchment area. The daily mean stages have been determined, during the summer half-year /that is, April 1 to September 30/ from readings taken at 07 a. m. and 07 p. m., while, during the winter half-year, from those taken at 08 a. m. and 04 p. m. Below the columns of daily mean stages, one will find the monthly characteristic stages /lowest, mean and highest stage/. In order to enable the comparison of the particular year with the average river regime, for every gauging station, the monthly and annual characteristic values of a decade havingnormal conditions and of the recent past as well as the extreme values /lowest and highest stage/ observed so far are displayed. The gauge readings of earlier years contained in this Annual are referring, in every case, to the actual gauge zero. In recent times, there were mainly in the early days of 1943 and 1946, some more important changes in the gauge zeros. Detailed information on this subject is yielded by the volumes 1943 to 1946 of the Annuals. The required corrections are summarized in a separate table /chapter A/5. /. 3-4. /The contents of these two chapters are closely interrelated, and Chapter 4 is even supplementing Chapter 1 in respect of a number of cross-sections. In Chapter 3, daily mean discharges tabulated prepared by using an electronical computer, while Chapter 4 is containing some more important discharge rating curves and discharge measurement-or gauge-cross-sections. In the table of daily mean discharges, those influenced by the presence of ice were denoted by the same symbols in the case of water stages. A reduction of discharge values affected by ice was not to be achieved in a reliable way, the number o£ available measurements in ice periods being too low. Below the daily data, monthly and annual characteristical data of the year in question and of the reference period, including extreme values of the year in question are shown. Beside the table the computer-processed discharge duration curves for the year in question and for the average of the previous decade are plotted. Below, we are presenting the characteristic values of the annual specific run-off for the same periods and, for convenience, the extension of the catchment is again quoted. Chapter 4, contains discharge rating curves, for stations with discharges tabulated in Chapter 3 . The curves are referring to discharges at the time of relative stage culmination, that is, a steady state of flow. For the sake of better legibility, the low-water sector of \the discharge curve has been magnified. For stations with no discharge statistics, a discharge table is given. For several stations, no reliable curve can be constructed because of the low number of measurements, and thus, for these stations, we are giving only the results of some discharge measurements. In this chapter, there are, in addition, cross-sections for some important gauges and or discharge- measurements showing extreme stages on the diagrams. It has been stated, whether the channel cross - section is referring to a gauge or rather to a nearby cross-section. 5. / In this chapter, the more important stage hydrographs have been compiled. The sequence of these curves is corresponding to the natural hydrographic system. For the sake of saving space there are, for each river, only a limited number of stage hydrograph, and generally only those which are necessary to form an idea on the pattern of water-level variations. Beside the curves, ice conditions are also plotted and at the appropriate places, also the,periods of storage are noted. 6. / Water temperature conditions are described in the chapter "Characteristic data of water temperature". Data are referring to morning temperatures measured at a depth of 20 to 40 cm below surface. For the sake of comparison, there are presented, beside the data referring to the year in question, characteristical monthly and yearly data of a number of years /generally a decade/together with the extreme values occurred so far. — 15 —
