Climate Change Tendencies in Climate Change Tendencies in Georgia under Global Warming Georgia under Global Warming

Conditions Conditions

Mariam Elizbarashvili1 Marika Tatishvili2

Ramaz Meskhia2

Nato Kutaladze3

1. Ivane Javakhishvili Tbilisi State University,1. Ivane Javakhishvili Tbilisi State University,

2. Georgian Technical University, Institute of Hydrometeorology2. 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.

The Black Sea coastal zone has a humid subtropical climate. The average The Black Sea coastal zone has a humid subtropical climate. The average annual temperature there is 14-15annual temperature there is 14-15OOC, with extremes ranging from +45C, with extremes ranging from +45OOC to -C to -1515OOC, and annual amounts of precipitation vary between 1,500 mm and C, and annual amounts of precipitation vary between 1,500 mm and 2,500 mm. The Black Sea influences the climate of West Georgia, resulting 2,500 mm. The Black Sea influences the climate of West Georgia, resulting in mild winters, hot summers and abundant precipitation. Here in the in mild winters, hot summers and abundant precipitation. Here in the mountainous and high mountainous areas, the annual air temperature mountainous and high mountainous areas, the annual air temperature ranges from 6-10ranges from 6-10OOC to 2-4C to 2-4OOC with an absolute minimum between -30C with an absolute minimum between -30OOC and -C and -3535OOC, and annual amounts of precipitation range between 1,200-1,600 mm C, and annual amounts of precipitation range between 1,200-1,600 mm and 2,000 mm.and 2,000 mm.

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 km2

Climate region

Mean airtemperature(OC)

Averagemaximumtemperature (OC)

Averageminimumtemperature (OC)

Annual sums ofprecipitation(mm)

Western Georgia

0.2 0.3 0.6 -27

Eastern Georgia

0.3 0.7 0.3 41

Change in air temperature and precipitation between climate norms Change in air temperature and precipitation between climate norms until 1960 and average values of the 1957-2006 perioduntil 1960 and average values of the 1957-2006 period

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 400-600 mm in the plains, and 800-1,200 mm in the mountains.

Hydrological posts

Meteorological posts

Meteorological stations

Source: National Environmental Agency

Dynamics of Changes of Hydrometeorological Observation Network Points

Temperature stations

precipitation stations

BLACK SEA

Data sources:1.The National Environmental Agency, Georgia

To restore data errors (missed data) following linear climatologic methods have been used:

METHODS

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 annual sum of atmospheric precipitations and corresponding equation of regression:

1 - Tbilisi; 2 - Poti

Multiyear flow of average annual air temperature and corresponding equation of

regression: 1 - Tbilisi; 2 - Poti;

3 - Kazbegi alpine

Precipitation distribution in 1936, Precipitation distribution in 1936, JanuaryJanuary

Temperature distribution for 1936 Temperature distribution for 1936 February.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 temperaturea) 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).   b) For atmospheric precipitationsb) 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).

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 January mean air temperature change oC in decade

Velocity of July 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 indicesAbbreviation and definition of the indices

Variable Abbreviation (unit)

Definition of extreme indices

Temperature Tmax (°C) Maximum air temperature

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

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.

(a)

(b)

Region Station Height M

IndicesIDO GSL TR20

The Black Sea Coastand Kolkhida lowland

BatumiPotiKutaisi

23114

000

355352350

323230

East Georgia TbilisiTelavi

403568

47

300295

2313

South-Georgian Upland

AkhalkalakiAbastumani

17171265

5728

200220

00

The Greater Caucasus KazbegiPasanauri

36531070

21021

0220

00

The average value of some climate indices in different physical and The average value of some climate indices in different physical and geographical conditions over the basic WMO period (1961-1990).geographical conditions over the basic WMO period (1961-1990).

Station Period Indices

SU30 TR20

Poti 1936-19601961-1990

1991-2011

8588

105

283243

Kutaisi 1936-19601961-1990

1991-2011

125122125

303040

Tbilisi 1936-19601961-1990

1991-2011

118116120

202326

Pasanauri 1936-19601961-1990

1991-2011

524865

000

Average value of the temperature indices for the different periods of averagingAverage value of the temperature indices for the different periods of averaging

CONCLUSIONSCONCLUSIONS 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%.

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! Thank you for attention!