Download 113 FOUR IMPORTANT NATURAL HAZARDS FROM ROMANIA

FOUR IMPORTANT NATURAL HAZARDS FROM ROMANIA
MARINESCU Mihai 1, STANCIU Christian 2, MARINESCU Georgeta 3
1
University of Bucharest, Faculty of Geology and Geophysics, Mineral Resource Management and
Center, 6 Str. Traian Vuia Street, [email protected]
2
INCD GeoEcoMar, 23-25 Dimitrie Onciul Street, Bucharest, [email protected]
3
High school “George Calinescu”, Bucharest
Environment
1. Hazards In Romania
In time, all subgroups of natural hazards (cosmic, geological, hydro-meteorological and
biological) have been recorded in Romania. Types of natural hazard are very numerous (over 50).
Sometimes, some of them have acted in periods of maximum vulnerability of the society and of the
environment, causing real disasters. The most numerous ones have been the hydro-meteorological
and perhaps the biological subgroups, followed by geological ones and, finally, with negligible
frequency and consequences, by the cosmic hazards. An attempt to classify the natural hazard
group known in Romania is presented in Table 1, detailed on subgroups, and subcategories.
Table 1. Natural hazards which affected or which may affect Romania.
SUBGROUPS
1.Cosmic
(astrophysics)
hazards
2.Geological
hazards
CATEGORIES
Cosmic corps fall
Cosmic corps clink
Cosmic corps blast
Hazards produced by internal factors of the Earth
Hazards produced by external factors of the Earth
SUBCATEGORIES
Movement of released soils, roks
and sediments masses
Movement of snow and ice masses
3.Hydrometeorologycal hazards
Movement of air masses
Movement of water
masses
Electrical discharges
Frost phenomena of water
Movement of fresh water
Movement of sea water
Movement of fresh and sea waters
Frost water in air
Frost water on rivers
Moisture deficiency
Excessive temperatures
Natural arsons
4.Biological
hazards
Epidemics
Epidemics caused by bacteria
Epidemics caused by viruses
Epidemics caused by rickettsii
Epizootics
Epidemics caused by toxins
Epidemics caused by unknown causes
For people and animals
For animals
Invasions of insects
TIPES
Meteors fall
Comets, asteroids,
stars clink
Gamma radiations
Earthquakes
Volcanic eruptions
Landslides
Falls, rolling land-slide or
crumblingof rocks
Avalanches
Storms, Blizzards, Tornados
Water flow, Torrents, Floods
Storm waves
Floods on the Danube
Lightnings, Thunders
Fogs, Hails
Ice floes, Ice bridges
Droughts
Very high temperatures
Very low temperatures
Arsons of forest
Arsons of land
Plague, Cholera, Anthrax, Leprosy,
Brucellosis
Smallpox, Encephalitis, Meningitis,
Malaria, Influenza, West Nile,
SARS, HIV
Foot and mouth disease, Typhus
Botulism
Balkan endemic nephropathy (NEB)
Cholera, Plague, Brucellosis, SARS,
Foot and mouth disease, Glanders,
Ornitoza-psittacosis
Pig pesta
Caterpillars invasion
Grasshoppers invasion
Various natural hazards (cosmic, geological, atmospherically, hydrological and biological)
have been recorded in Romania. Nevertheless, four from the most important hazards, regarding the
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number of dead or affected persons, or economic damages, are the earthquakes, floods, droughts
and excessive temperatures.
2. Earthquakes
In connection with earthquakes felt in Romania, there are several main epicenter areas
(Vrancea, Fagaras, Banat, and Black Sea), some minor areas and regions in the neighborhood
countries. The most important, by energy and frequency effects, are Vrancea earthquakes. The
seismic activity is mostly located at depths of 70-160 km (intermediate depth), in an epicenter area
of approximately 2000 km2
There is also some minor crustal activity with depths down to 40 km, extending on an area
up to 7000 km2. Inside the Carpathian arc, they felt relatively weak. Usually, intermediate depth
earthquakes of moderate magnitude are single shock ones, but the strong events are accompanied
by numerous replicas. The November, 10th, 1940 event has a magnitude of 7.4.
Fagaras earthquakes are polikinetic ones (multiple shocks). They have a long duration and
moderate intensity, reaching up to VII (Lazarescu, 1980). The hypocenter depth is crustal one (1020 km), they being connected to several major fault systems separating Transylvania from the
Fagaras Mountains. Banat earthquakes (Danubian ones) are generated along the fractures of the
basement, being located between the Varset Massif (in Serbia), Vinga and Moldova Noua. They are
polikinetic events (multiple shocks) with normal depth. They have reached the intensity up to VII
and their macro seismic area is narrow.
The Pontic earthquakes are located in the proximity of the Black Sea coast, usually between
Mangalia and Sabla area (Bulgaria). They occur frequently (2-3 per year), are polikinetic ones and
have a low energy. Their occurrence is at the intersections of several important faults, both on land
and on the sea self. Almost twice the millennium such destructive earthquakes have been recorded
on the Bulgarian territory.
The secondary epicenter areas are related to faults of the basement, occurring at depths of
10-20 km. They have a local nature. Most active are those connected with parallel fractures limiting
the East-European Platform, after then it goes down in steps to Carpathian orogen (Botosani
Dorohoi and Avramesti Barlad); the ones related to the extension towards North and East, at a
basement level, of several faults of North Dobrudja orogen (Tecuci-Tudor Vladimirescu,
Marasesti-Focsani-Namoloasa, Tulcea-Isaccea-Galati); also the earthquakes located in the area of
faults placed in the basement of the central part of Transylvania Depression (Tarnavelor area).
On the Romanian territory, earthquakes having the epicentral area in neighboring countries
(Bulgaria, Serbia) or in Greece or Turkey are also recorded. The Bulgarian ones are placed on the
trench structure existing along Marita river, or are linked to the fault system limiting Rhodopi
Mountains. Earthquakes in Serbia are associated to the trench existing along Morava valley.
3. Floods
Floods are among the most popular in the area and most common hazard that occur in
Romania, sometimes having great economic and social consequences. Floods usually take place
over the course of internal rivers and of the Danube. In these cases a small river having usually
small debits, increase dramatically the amount of transported water, producing on overflow and
filling the major riverbed. Annual occurrence is around 10-15 floods, with greater frequency at
medium altitudes (in the mountains and Sub-Carpathians) and lower frequency towards the plain.
Catastrophic floods are produced every 50 -100 years because of torrential rains combined with
sudden snow melting. They are most frequently occurring in the western part of the country.
Spring held regularly floods by melting snow, above which the overlap of spring rains. At
the beginning of summer, they are wide spread in the country, being due to heavy rain. Autumn are
rarer, due to rainfall during October-November and having a higher frequency in Banat and
Oltenia. It is estimated that the maximum exposed flooding in our country is about 3.5 million ha,
representing 15% of the country. In 2005, damage to the national economy has exceeded 1.7 billion
dollars. For the floods from 2010, the damage was not yet calculated.
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4. Droughts
Droughts occur in May and have drastic effects in the areas of plain, non-irrigated land. In
Baragan and Dobrogea, the average duration of dry intervals is over 20 days, in the Romanian
Plain, in the Plateau of Moldavia is 15-19 days, and for the rest of the country is about 17 days.
Although droughts can register throughout all the year, the most numerous are produced in late
summer and early autumn. The territories, which are exposed to drought, are in the Southeast of the
country (Baragan, Dobrogea, Moldova Southern Plateau).
Throughout the whole country, drought in the summer of 2000, extended until the winter of
2001, has been the strongest of the past 100 years. It affected over 3.7 million hectares of land. The
river has fallen considerably, the Danube has been the lowest level from 1840 onwards (when it
started to be monitored its level). It was affected also the national energy system due to a low level
in lakes. Damage to the national economy has exceeded 3 billion dollars.
5. Excessive Temperatures
Excessive temperatures which is not usual in the area of Romania, with temperate climate,
those are either too high during summer or in winter too low. They persist for several days in a row.
Temperatures too low or too high are not proper to human bodies when persist a longer period.
Very high temperatures accompanied by excessive moisture, are usually caused by warm air
masses, coming from Africa across the Mediterranean Sea. They may cause, especially in urban
areas, a number of deaths among young children, and aged, sick and disabled people. When the
heat wave persists for a longer period, drought can occur, triggering fires (in the woods or areas
with dry vegetation). Alternatively, they are activated epidemic outbreaks of epizootic diseases,
putting in danger the agricultural-forest fund.
References:
Balteanu, D., Alexe, R., 2001. Natural and anthropogenic hazards. Corint publishing house
Grecu, F., 2006. Natural hazards and risk. Universitara publishing house. Bucharest.
Lazarescu, V., 1980. Physical geology. Technical publishing house. Bucharest.
Marinescu, M., 2006. Natural disasters. International University Press. Bucharest
Marinescu, M. et al., 2007.Natural and technological hazards that can produce disasters in Romania.
Evaluating the risks and measures of preventing and limiting the impact on the society and the
environment. Partnerships in priority area.1st – 4th stages. CNMP archives. Bucharest.
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