Prevailing winds in Northern Serbia: recent data, geomorphological evidences and numerical Simulations

Abstract

The prevailing winds are explored in Northern Serbia, examining the aeolian processes, especially in the southeastern part of the Carpathian (Pannonian) Basin in the area in and around the Banatska Peščara (Deliblato Sands). In this study, four different methodological approaches were used. The first two approaches are based on the identification of prevailing winds using climatological data on winds and synoptic data on atmospheric circulations from the recent period. Geomorphological records and numerical simulation were used as the second two approaches to determine prevailing winds in the past. Recent prevailing winds in Northern Serbia have been encountered mainly in the fourth (270°-360°/00°) and second (90°-180°) quadrants with frequencies of 113.5 and 102.2 days a year, while their frequencies within the area of Banatska Peščara are 106.0 and 121.0 days per year, respectively. The crest directions of the Banatska Peščara dune field confirms that of about 1300
dunes, the vast majority of parabolic dunes (approximately 1200 dunes) show direction of the second quadrant, which is dated to the Early Holocene, while the remaining ones, the so-called, transversal dunes have shifted their direction to the third quadrant. The grain size analyses of loess deposits around the Banatska Peščara shows a main accumulation of aeolian particles from south-east to north-west (prevailing winds from the second quadrant) and probably represent the period between the Last Glacial Maximum (LGM) and the Holocene. Modern wind measurements and geomorphological results showed that the prevailing winds in the recent and past periods were from the same, second, quadrant in and around the Banatska Peščara. These results were confirmed with an explicit numerical simulation of atmospheric circulation that created prevailing winds from the second quadrant in the LGM period. The phenomenon of prevailing winds in Northern Serbia is the result of the interaction of atmospheric circulation of different scales over the European continent, especially in Southeastern Europe. The main carrier of this interaction is the undulation of the Polar front, which, due to the constant change of form and position, creates distinctive types of
weather. Thus, the winds from the second quadrant are most often dry and usually cause weather conditions without precipitation, while winds from the fourth quadrant usually create advection of moist air and precipitation. This alternation of dry and wet winds show a great similarity with the shift of dry and wet monsoons in Asia, but with one difference. Monsoons are replaced every six months, while the dry and moist winds in Northern Serbia alternate many times a year and their total duration
amounts to 227.0 days a year in the area of Banatska Peščara.

Resources

Bibliography

Gavrilov, M., Markovic, S., Schaetzl, R., Tosic, I., Zeeden, C., Emunds, K., Sipos, G., Ruman, A., Putnikovic, S., Obreht, I., Peric, Z., Lehmkuhl, F. (2016): Prevailing winds in Northern Serbia: recent data, geomorphological evidences and numerical Simulations. Loess2M - Modelling & Mapping. 26-29.8. 2016, Novi Sad, Serbia.