Transcript Climate change tendencies in Georgia under global warming

Climate Change Tendencies in Georgia under
Global Warming Conditions
Mariam Elizbarashvili 1
Marika Tatishvili 2
Ramaz Meskhia 2
Nato Kutaladze 3
1. Ivane Javakhishvili Tbilisi State University,
2. Georgian Technical University, Institute of Hydrometeorology
3. The National Environmental Agency, Georgia
Mountains cover a significant part of the
territory: 54% of it is located at an
altitude of 1,000 m above sea level.
Almost every climatic zone is represented
in Georgia except for savannas and
tropical forests.
area - 67,900 km
Mountains
cover a significant part of the territory: 54% of it is
located at an altitude of 1,000 m above sea level.
2
The Black Sea coastal zone has a humid subtropical climate. The average annual temperature there is 1415OC, with extremes ranging from +45OC to -15OC, and annual amounts of precipitation vary between
1,500 mm and 2,500 mm. The Black Sea influences the climate of West Georgia, resulting in mild winters,
hot summers and abundant precipitation. Here in the mountainous and high mountainous areas, the
annual air temperature ranges from 6-10OC to 2-4OC with an absolute minimum between -30OC and 35OC, and annual amounts of precipitation range between 1,200-1,600 mm and 2,000 mm.
The climate in the plains of East Georgia is dry: in the lowlands, it is a dry
subtropical climate, and in mountainous areas it is alpine. The average annual
temperature is 11-13OC in the plains, and 2-7OC in the mountains. The absolute
minima are -25OC and -36OC respectively. The absolute maximum reaches +42OC,
and the absolute minimum falls to -42OC in the high mountains (the slopes of
Mount Kazbegi). The annual amounts of precipitation vary in the range of 400600 mm in the plains, and 800-1,200 mm in the mountains.
Change in air temperature and precipitation between climate norms
until 1960 and average values of the 1957-2006 period
Climate region Mean air
Average
temperature maximum
(OC)
temperature
(OC)
Average
minimum
temperature
(OC)
Annual sums of
precipitation
(mm)
Western
Georgia
0.2
0.3
0.6
-27
Eastern
Georgia
0.3
0.7
0.3
41
Dynamics of Changes of Hydrometeorological Observation Network Points
Meteorological posts
Meteorological
stations
Hydrological posts
Source: National Environmental Agency
BLACK SEA
Temperature stations
precipitation stations
Data sources:
1. The National Environmental Agency, Georgia
METHODS
To restore data errors (missed data) following linear climatologic
methods have been used:

1. Method of corresponding differences

2. Method of corresponding divisions.
Figure shows an example of comparison of actual and estimated average monthly
temperatures in January at the Kazbegi alpine station over the period between 1936
and 1990, when this station was operational.
Dependence between actual (x) and estimated (y) average January temperature at the Kazbegi
alpine station over the period between 1936 and 1990,
R2 determination coefficient
Multiyear flow of average annual air
temperature and corresponding
equation of regression: 1 - Tbilisi;
2 - Poti;
3 - Kazbegi alpine
Multiyear flow of annual sum of atmospheric precipitations and corresponding
equation of regression: 1 - Tbilisi; 2 - Poti
Precipitation distribution in 1936, January
Temperature distribution for 1936 February.
The whole territory of Georgia was divided by 25 km. grid so that the territory have
to be covered as many points as possible. So the 112 pointed 25 km. grid was created.
Depending on the intensity of warming (cooling), the following gradations of rate of
changes were nominally determined:

a) For air temperature

• Strong cooling (less than -0.10 ՕС during 10 years);
• Moderate cooling (-0.06- -0.10 ՕС during 10 years);
• Weak cooling (-0.02 - -0.06 ՕС during 10 years);
• Unchanged (-0.02- 0.02 ՕС during 10 years);
• Slight warming (0.02-0.06 ՕС during 10 years);
• Moderate warming (0.06-0.10 ՕС during 10 years);
• Strong warming (over 0.10 ՕС during 10 years).
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b) For atmospheric precipitations

• Significant decrease (less than -5% during 10 years);
• Moderate decrease (-3.1- -5.0% during 10 years);
• Insignificant decrease (-1.1- -3.0 % during 10 years);
• Unchanged (-1- 1% during 10 years);
• Insignificant increase (1.1- 3.0% during 10 years);
• Moderate increase (3.1- 5.0% during 10 years);
• Significant increase (over 5% during 10 years).
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Development and validation of 1936-2011 year high resolution monthly gridded temperature and
precipitation data set for use in global climate change assessment for Georgia.
Velocity of annual mean air temperature change oC in decade
Velocity of July mean air temperature change oC in decade
Velocity of January mean air temperature change oC in decade
Precipitation annual sum variation velocity % in decade
METHODS
Climate extreme indices (CEIs) used in this study are approved as core indices
by the CCl/CLIVAR/JCOMM Expert Team on Climate Change Detection and
Indices (ETCCDI)
 Climate extreme indices have been assessed using R and the RClimDex1.0
software.
 Homogeneity and quality of the time-series were tested by the software
package RHTestsV3
 GIS

Abbreviation and definition of the indices
Variable
Temperature
Abbreviation
(unit)
Tmax (°C)
Definition of extreme indices
SU30 (days)
Number of hot days (with T max above 30°C)
IDO (days)
Number of frosty days with the negative maximum
air temperature
GSL (days)
Number of days when the daily temperature exceeds
5°C
TR20 (days)
Number of tropical nights with the minimum air
temperature exceeding 20°C
Maximum air temperature
(a)
(b)
Geoinformational maps of classification of
maximum air temperature (a) Tmax and
number of hot days (b) SU30 during a year
within the period of 1961-1990.
The average value of some climate indices in different physical and
geographical conditions over the basic WMO period (1961-1990).
Region
Station
The Black Sea Coast
Batumi
and Kolkhida lowland Poti
Kutaisi
East Georgia
Tbilisi
Telavi
South-Georgian
Akhalkalaki
Upland
Abastumani
The Greater Caucasus Kazbegi
Pasanauri
Height
M
Indices
IDO
GSL
TR20
2
3
114
403
568
1717
1265
3653
1070
0
0
0
4
7
57
28
210
21
355
352
350
300
295
200
220
0
220
32
32
30
23
13
0
0
0
0
Average value of the temperature indices for the different periods of averaging
Station
Poti
Kutaisi
Tbilisi
Pasanauri
Period
1936-1960
1961-1990
1991-2011
1936-1960
1961-1990
1991-2011
1936-1960
1961-1990
1991-2011
1936-1960
1961-1990
1991-2011
Indices
SU30
TR20
85
88
105
125
122
125
118
116
120
52
48
65
28
32
43
30
30
40
20
23
26
0
0
0
CONCLUSIONS

The presented maps show that changes in temperature and precipitations in the territory of Georgia under
global warming conditions are not of uniform nature due to complicated physical and geographic, and
basically, orographic and landscape-climate conditions. Largest spots and territories of strong warming, when
an average annual temperature increased by more than 0.1ՕС during 10 years, are observed in eastern
Georgia. Spots of weak and moderate warming with the temperature increasing at the rate of 0.02-0.1ՕС
during 10 years, are observed in western Georgia.

Over an insignificant part of Georgia, temperature remained almost unchanged or changed insignificantly.
Decrease in temperature is observed mainly in western Georgia. Strong cooling occurs in a significant part of
Adjara and northern part of Black Sea coast where an average annual air temperature decreased at the rate of
over 0.1ՕС in 10 years.

Over a significant territory of East Georgia, annual sums of precipitation decreased at the rate of 1-3% during
10 years. The highest rate of decrease in precipitation is observed in Kvemo Kartli (south of Tbilisi),
comprising more than 5% in 10 years. Increase in annual sums of precipitation is observed in several districts
of West Georgia as well as in the central part of Iori Plateu in East Georgia where the annual sum of
precipitation increased at the rate of 1-3% during 10 years. In mountainous Adjara and some other districts of
Black Sea coast, the rate of increase in precipitations reached 5%.
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For the period of 1991-2011, compared to the years of 1936-1960, the number of hot days has increased to 20.
And the number of tropical nights-to 15. Compared to the basic WMO periods (1961-1990) – these changes
made up 18 and 11 days respectively. The number of tropical nights in Tbilisi has increased to 6 days
compared to the period until 1960. In Pasanauri, on the south slope of the Greater Caucasus, for the last
period compared with the period of averaging, recommended by WMO (1960-1990) the number of hot days
has increased to 17.
Thank you for attention!