Vízügyi Közlemények, 1934 (16. évfolyam)
4. szám - XI. Szakirodalom
18 predetermined and expected, and navigation at low water is fully secured. These researches are based on frequency curves and stages of icefree low waters (fig. 8 and 9), as well as on discharge diagrams. III. The flood of 1926 from the point of view of hydrometeorology. (With the collaboration of Dr. L. Aujeszkv). This part, which has been prepared with the aid of synoptic maps by the Breslau-Krietern observatory and official publications of other institutions, deals with the météorologie conditions of the flood in 1926. This memorable flood induced the interested States to study more particularly the régime of the Danube. The full text of this study, in French and German, can be obtained on application to the editorial offices of this periodical. III. THE REGIME OF THE DANUBE : ITS METEOROLOGIC RELATIONS. BY DR. L. AUJESZKY. 1. Hydrometeorology deals, on the one hand, with the origin of precipitated water, and, on the other, with the météorologie factors (such as wind, temperature, evaporation) influencing the path of water falling in the watershed area. 2. From the point of view of hydrometeorology all considerable precipitations are due to the same atmospheric cause : the ascending movement of larger masses of air. The cause of the ascension may be some topographic obstacle (this causes a barrier 'precipitate ), or the concurrence of different sorts of air ( frontal precipitate) . 3. The author describes the kinds of fronts : ascension front, invasion front, and stationary front. He points out the different hydrometeorologic natures of these fronts, and especially emphasizes the great importance of stationary fronts for the régime of rivers. 4. On the basis of these general principles the most important météorologie factors governing the régime of the Danube may be determined. The monsum fronts in the months of May and June, which accumulate on the Alps, produce heavy rainfalls and bring about the great floods of the Upper-Danube. The water levels in late summer are principally governed by the climatic conditions of the high mountains. The rainfalls in autumn originate from Mediterranian ascension fronts which repeatedly take up such a position as to cause frontal precipitate in the southern and eastern Alps (in the watershed of the Drave river), while at the same time the Upper-Danube and its tributaries recieve considerable barrier precipitate. IV. RAINFALL CONDITIONS OF THE HUNGARIAN GREAT PLAINS AND METEOROLOGIC REASONS FOR THEIR AFFORESTATION. BY DR A. RÉTHLY. This article is a reply to the paper by M. K. Kaan, entitled „Influence of afforestation and plantation on local microclimatic conditions of Lowlands", which appeared in the Vízügyi Közlemények (1933. Vol. II.).
