Cordoneanu, Elena (N.I.M.H. of Romania)
Ivanivici, Vladimir (same affiliation)
Banciu, Doina (same affiliation)
Dragulanescu, Liviu (same affiliation)
Soci, Cornel (same affiliation)
Over the region between the Carpathians and the western and north-western part of the Black Sea, sever weather events, particularly strong cold winds associated with more or less significant snowfalls, are recorded every winter season. The large scale pattern is defined by a Mediterranean cyclone located in the eastern basin of the Mediterranean Sea having the tendency to extend over the Black Sea and a cold anticyclone coming from North, North-Esat over the Carpatho-Pontic region. Mesocale effects related to the Carphatian chain and Black Sea are capital for the occurrence of such sever weather in Romania. Climatologically, this situation is well expressed by the regional wind called CRIVATZ. Rather often, this kind of situations, characterised by 2-3 day systematic persistence, produce serious damages. The cold wind can reach sustained speed of 15 to 20 m/s drifting the previous or the falling snow. Important efforts have been devoted to improve the knowledge and the prediction of this wind but, unless the observing network is improved significantly (for instance through pilot projects of enhanced observations over limited time periods), further progress can only be achieved through advanced numerical modelling. In this paper, after a short description of the present knowledge on the Crivatz, a numerical simulation of a cse study is presented. The experiments have been performed using Aladin model, a spectral limited area model, which is now in the preoperational stage on a workstation at NIMH, Bucharest.
The results show that the Aladin model describes very well the specific behaviour of the low level flow induced by the Carpathians and the Black Sea; many details of the wind field are noticied.