THE ROLE OF AIR ADVECTION AND ATMOSPHERIC STABILITY INDICES FOR IDENTIFING HEAVY RAIN STORMS IN NORTH-WESTERN ROMANIA
TUDOSE T., MOLDOVAN F.
ABSTRACT. - The role of air advection and atmospheric stability indices for identifying heavy rain storms in north-western Romania. Air advection and convection at different levels in the atmosphere affect its vertical stability. The degree of stability / instability can be determined by using vertical wind profile (hodograph) and stability indices. Analysis of these two elements was used to determine the degree of atmospheric instability for heavy rains in north-western Romania, for the warm season of the 2010-2012 period. The hodographs were made using the atmospheric soundings in Cluj-Napoca, which permitted to determine the air advection intensity between different layers of the atmosphere (sea level-925 hPa, 925-850 hPa, 850-700 and 700-500 hPa). The atmospheric stability indices were used to calculate the intensity of instability. The results show that for an unstable environment a warm advection in the lower layers of the atmosphere and a cold one, in the middle layers are needed. On the other hand, in the case of stability indices, the most useful for assessing atmospheric instability are those that include data about air moisture near the ground level.
Keywords: air advection, hodograph, atmospheric stability indices, rainfall, north-western Romania.