The climatic and
agroclimatic characterization ofJanuary
in the Republic of
Moldova
In Moldova, January is
the coldest month of the year. The monthly average air
temperature
varies between -2.5ºC in the southern part and -4.5ºC in the northern
part of the territory.The coldest month of January for the
entire period of instrumental measurements on the biggest part of the
territory was in 1963 – the monthly average air temperature
ranged between -10.5°C (Cahul) and -15.3°C (Soroca). The
warmest month of January was recorded in 2007 - the
monthly average air temperature was between +2.5ºC (Briceni)
and +4.2ºC (Bravicea).
The average values of dailyair temperature during the monthoscillates between-20…-29ºC (1963) and +8…+11°C (1948). The absolute
minimum air temperature for the whole period of observations was
-35.5°C (Bratuseni, Edinet, 01.20.1963) and absolute maximum
reached +16.0°C (Dubasari Bravicea, 21.01.2007).
The number of days with
minimum air temperature ≤ -10 ° C on the average is5-11
days, the maximum recorded being 27 days (Briceni, Camenca,
1987).The number of days with minimum air temperature ≤ -15°C
on the average is 1-5 days, and the maximum has reached 23
days (Soroca, Camenca, 1963).
The number of days with minimum temperature ≤ -20°C does not
exceed the average of 1-2 days, but in some years may reach up to 17
days (Camenca, 1963).
The amount of rainfall in
January in the country constitutes 22-41 mm and the number of
days with precipitation - from 10 to 15. The greatest amount of
precipitation in January, for the entire period of instrumental
observation on the territory, has reached 216 mm (Carpineni,
1966), while the daily amount - 55 mm (Cahul, 1966).
Precipitations fall mainly
in mixed phase (about 35% of the time) and as snow (about 40% of the
time). The decadal average thickness of snow in the territory
varies from 2 to 10 cm. The maximum thickness of snow on
the meteorological platforms on certain days has reached 63 cm
(01.06.1966, Cahul). The steady snow cover is formed in the
northern and northeastern districts of the country, on average, in the
first decade of January (which is maintained for at least 30 days).
In January, the following
phenomena are possible: fog (average 3-10 days), frost and ice
deposits (average 4-9 days), ice-slick (average 7-19 days)
and blizzards.
Of most frequently
observed weather events
are heavy snowfalls, that are possible on average once every
three years. Rarely, there are recorded powerful storms,
intense deposits of frost and ice (on average once in 8-10 years)
and strong winds (on average once in six years). A fall in air
temperature down to -25ºÑ and below average may signal once 7-15
years in the northern half of the country and once in 30-50 years - in
the southern part.
In January, the autumn
crops are basicly in the dormant state. In the years with mild
winters, there are thaws that are dangerous for the hibernating
crops. These are frequent phenomena in the country. The most dangerous
are thaws with the average daily temperature of +5°C and higher. During
these, it takes places the reversal of autumn crops vegetation and that
of the orchards, and in the case of a sudden drop in temperature it is
possible their further injury. In January, the number of days
with thaw is on average 12 to 18 days.
In the winter period the
worst conditions for wintering of autumn crops air are created at
the minimum temperature of -25°C and lower, in the presence of snow
cover whose thickness does not exceed 5 cm.In such
conditions the minimum temperature at the depth of the twinning node
(3 cm) falls below -15°C. Such temperatures can cause injury, and even
destruction, of the twinning node, and therefore, of the whole plant.
Such combination of air temperature and snow cover on most of the
country territory is observed, on average, once in 20 years, and are
reported most frequently in January.
According to the multiannual
observations, the autumn crops wintering, with plant loss up to 10-30%,
occurs on most of the territory on average once every 5-15 years, but
plant loss up to 50% - on average time in 20 years.
The crowns of fruit trees
and their flower
buds can withstand frosts of up to -25 ... -30°C. In the
conditions of the Republic of Moldova the damage of fruit crops can be
observed more frequently after long winter thaws, which significantly
reduces tree resistance to frost.
In the period of relative
rest, the vine generally bears temperatures up to -12°C, and
some species up to -15…-20°C. The average vine mesh destruction does
not exceed 10-20%.