First International Conference on MOLDAVIAN RISKS – FROM ...

<strong>First</strong> <strong>International</strong> <strong>Conference</strong> on MOLDAVIAN RISKS - FROM GLOBAL TO LOCAL SCALE
16-19 May 2012, Bacau, Romania
RESEARCH ON THE CAUSES OF TORRENTIAL RAINS IN
THE CENTRAL SOUTHERN OF MOLDAVIAN REGION
ON 05 SEPTEMBER 2007
Maria Vasilica 1 , Doina Capsa 1 , Irina Covaci 1 , Valentin Nedeff 2 ,
Narcis Barsan 2
1 Regional weather forecasting service Bacau
2 “Vasile Alecsandri" University of Bacau, Department of Environmental Engineering and
Mechanical Engineering
Corresponding author: Capsa Doina, doina_capsa@yahoo.com
Abstract: Precipitation is defined as water falling from atmospheric layers to the surface of
the earth. All precipitation contributes to the water circuit in nature. At the national level
the atmospheric precipitation increases from east to west and from the lowlands to the
highlands. Mean annual precipitation in the Danube Delta and on the seashore hardly
reaches 400 mm per year, increasing to 500 - 600 mm per year in the lowlands and
exceeding 1000 mm per year in the highlands. The mean annual precipitation varies a lot
from one year to another. Even if mean annual precipitation doesn’t exceed the
multiannual average, the most important problems occur when a large quantity of
precipitation falls in a very short period of time. This paper studies the main causes that
determined the torrential rains on the 5th of September 2007. The main characteristics of
that day consisted in the torrential rains that occurred over the central-south part of
Moldavia between 9 am and 12 pm. The convective clouds developing above the northern
part of the Romanian plain followed a certain path over the central-south part of Moldavia,
finally leading to quantitatively significant torrential rains. Synoptic situation in the
context of floods that occurred in the south of Moldavia in the period studied is as follows:
on 05.09.2007 in the area where floods have occurred under the influence of a depression
from Minor Asia. At continental level has occurred a particularly barometric phenomenon
from NE to SW of Europe. The Azores anticyclone was extended on the western half of
the continent and the European part of Russia was under the influence of an anticyclone
nucleus. Under the Azores anticyclone dorsal there has been a connection between two
active cores, one located in the SW part of Bulgaria, Greece's N and NW Russia's. Six
hours after production, this phenomenon has moved from west to east and in this time the
Azores anticyclone has expanded a dorsal to the north central parts of Europe.Also, this
paper presents the social and economic impact of significant floods on the local
communities from the affected areas.
Key words: precipitation, convective clouds, torrential rains.
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