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1. State of the Environment
1.1. Atmospheric Processes and Phenomena
1.1.1. Climatic Particuliarity
Moldova benefits of a temperate-continental climate. Winters are usually mild and short with
little snow. Summers are warm and long with limited rainfall. Alongside with favorable climatic
particularities this area is susceptible to droughts and has a changeable weather.
The main factors determining climate peculiarities are: the influx of solar radiation, the
atmospheric circulation and the specific landscape.
The atmospheric circulation in this region is influenced by different baric centers: the
Mediterranean cyclones, Siberian anticyclone, Azores anticyclone and Scandinavian anticyclone.
The air masses, crossing through the main baric centers, reach Moldavian territory with modified
physical characteristics, determining the succession of weather conditions in the Republic of
Moldova. Most air masses reaching Moldova are dry and this explains the high frequency of
droughts, occurring practically in all seasons.
The irregularities of the earth surface induce local climate changes. However, their influence is
negligible due to the advections occurring almost simultaneously all over the country in natural
condition, which limit their manifestations.
The summary annual duration of sunlight varies from 1940 to 2180 hours, with 60-70% during
summer and 20-30% during the winter. The potential of solar energy amounts to 2100 MDj/m2
per annum. The average yearly air temperature is 8-100 C, and soil temperature (at the surface),
10-120C. The free-of-frost period constitutes, on average, 170 days in the north of the country
and 190 days in the south. In certain years, this period can reach 200-230 days.
The Republic of Moldova is located in a region of insufficient humidity. The average annual
amount of precipitation goes down from 620 mm at the north-west to 490 mm at the south-east.
The precipitations fall predominantly in the warm period of the year as heavy rainfalls and only
about 10% of yearly quantum falls as snow.
The winds predominantly blow from north-vest (12-35% per annum) and south-east (15-25%),
with an average velocity of 2.5 to 4.5 m/s.
The circulation processes play a major role in determining the meteorological conditions in
winter time. Due to the prevalence of the western gradient, different kinds of air masses get
through the country - from arctic-continental to tropical-continental and maritime. As a result of
the frequent changes of air masses in winter, the air temperature may show significant
fluctuations within short periods of time. The coldest month is January, with average
temperatures of -2.5…-5.50C. In some days, the air temperature can fall down to -28…-360C.
The total precipitations during winter amount to 100-140 mm (about 20% of the yearly quantity),
being mostly mixed as sleet and snow. A stable snow cover usually occurs at the end of
November – beginning of December. It has a slight thickness: on average, only in one winter out
of ten it may reach 50 cm in the north of the country and 20-30 cm in the center and south.
Snowstorms and hoar frosts are not unusual during winter time (on average 5-10 days the former
and 10-30 days the latter).
In spring, the weather is very unstable, especially in March. The air temperature is rising fast and
the soil warms up rapidly. In the second half of April the average temperature reaches 14-160C.
The frequent late spring frosts (sometimes even in May) adversely affect the agriculture crops,
causing severe damages. As the air temperature goes up, the relative humidity goes down
reaching its lowest annual values (60-70%). The monthly precipitation rate in this season
constitutes 30-65 mm. Poor rainfalls, low relative humidity and strong winds increase the
susceptibility of the territory to droughts.
The summer is warm and dry. The warmest month is July, with average air temperature of 19220C and maximums of 37-400C. The average soil temperature in July is 24–270C, reaching in
some days 62-660C. The summer months in Moldova are the richest in precipitation (65-90 mm
in June-July). The rains are usually quite intense: the maximum rainfall within 24 hours ranges
between 70 and 220 mm.
The autumn is warm and long. In October the average daily air temperature exceeds +100C, and
in first half of November it exceeds +50C. The average precipitation in October amounts to 2050 mm. In October-November the first snow falls down.
The last decade (1990-1999) had a higher temperature regime as compared to multi-annual data:
the average annual air temperatures have marked 8.4 - 10.10C, exceeding the multi-annual
average by about 0,50C. In 1990 and 1994 the highest values (9.5 – 11,50C) of all period of
observations (over 100 years) were recorded. The lowest values (7.1 – 9.30C) were registered in
1996 and 1997. The average temperatures showed to be particularly higher in winter, spring and
summer. Thus, the average air temperature through the winter season was -0.9…-2.30C, by 0.21.40C warmer than the multi-annual values. Nine winters out of the last ten were milder than
average and only in 1995-96 it was colder than usual. The winter of 1989-90 was the warmest
one, with average seasonal temperature in Chisinau of 80 C, while in certain days of February the
temperature rose to 21.50 C.
The springs over the last decade were, on average, 0,50C warmer than the multi-annual average
while in summer the average temperature exceeded the multi-annual values by 0.5-0.90C. In
autumn the temperature regime (8.1-10.20C) was close to the multi-annual values.
The yearly precipitation rate in 1990-1999 was 536-615 mm, within the average values
calculated over the entire period of instrumental observations. The rainfall rate is, however,
subject to significant fluctuations, from 300 mm (1990) to 890 mm (1998).