







































Georgian Geographical Journal 

Assessment of the Climate Change Impact 

on the Characteristic Parameters of 

Freezing in Georgia by Regions 
Naili Kapanadze1,* , Marika Tatishvili1,2* , Irine Mkurnalidze1

, Ana Palavandishvili1,2  
1 Weather Forecast and Disaster   Modeling Department of Institute of 

Hydrometeorology of Georgian Technical University, Tbilisi, Georgia 
2 

TSU, Vakhushti Bagrationi Institute of Geography, Tbilisi, Georgia
 

* Corresponding author: m.tatishvili@gtu.ge 

 

 

 

 

 

 

Introduction 

Agriculture is widely recognized as one of the most vulnerable sectors to climate change across the 

globe. Variations in temperature and precipitation regimes, evapotranspiration rates, and soil 

moisture—along with the increasing frequency of extreme weather events such as droughts, floods, and 

heavy rainfall—lead to soil degradation, erosion, and nutrient depletion. These processes reduce 

agricultural productivity and negatively impact both the quantity and quality of food production. 

In Georgia, complex topography, diverse meteorological conditions, and significant anthropogenic 

pressures create particularly favourable conditions for the occurrence of various natural hazards. Recent 

decades have seen a marked increase in the frequency of such events, driven by deviations from long-

term climatic norms in precipitation, air temperature, humidity, and other meteorological parameters. 

These deviations amplify the occurrence of catastrophic processes within the broader context of global 

climate change. 

Among the hydrometeorological hazards affecting Georgian agriculture, frost represents one of the 

most significant threats. Notably, frost—despite its substantial impacts—has not been included in the 

internationally standardized classification of hazards established by the United Nations in the 2015 

Sendai Framework for Disaster Risk Reduction (Sendai Framework 2015–2030) (NDRR / ISC Sendai 

Hazard Definition and Classification Review, Technical Report, 2019; Kapanadze et al., 2023). 

Nonetheless, frost continues to inflict considerable damage on agricultural systems in Georgia, as well 

as in many other countries worldwide (Mkurnalidze et al., 2023). 

Given this context, there is growing scientific interest in assessing the impacts of contemporary 

climate change on frost characteristics across different regions of Georgia. Such assessments require 

the analysis of observational data from individual meteorological stations, which are located within 

diverse climatic zones and may therefore exhibit variations in frost dynamics under changing climatic 

conditions (Kapanadze et al., 2023; Kapanadze et al., 2024). 

Accordingly, the central objective of this study is to quantify changes in the frost-free period—a key 

temperature-based indicator of climate change—and to determine the average timing of the last spring 

frost and the first autumn frost across different regions of Georgia. This regional approach will allow 

Georgian Geographical Journal, 2025, 5(2) 12-16 

© The Author(s) 2025 

 
This article is an open access article distributed under 

the terms and conditions of the Creative Commons 

Attribution (CC BY) license (https:// 

creativecommons.org/licenses/by/ 4.0/). 

DOI: 

https://journals.4science.ge/index.php/GGJ 

Abstract 

The change tendency in the duration of the frost-free period in the territory of 

Georgia is analysed by comparing the last 16 years of data (2007-2022) with 

the similar one of the previous periods (1951-1965). The early, average and 

late values of the last spring and first autumn frost dates in the study regions 

were evaluated. It was revealed that in the period 2007-2022 compared to 

1951-1965, the average values of frosts shifted earlier for the last spring frost 

and later for the first autumn frost, which led to frost-free periods increasing 

and, accordingly, the length of the vegetation period. The map depicting the 

duration of increased frost-free periods is presented, the trend of increasing 

frost-free periods under climate change is revealed, and the dependence of 

these periods on the North Atlantic Oscillation is also fixed. 

Keywords: Spring and autumn freezing, frost-free period, growth trend, 

North Atlantic Oscillation 

Citation: Kapanadze, N.; Tatishvili, M.; 
Mkurnalidze, I.; Palavandishvili, M. 

Assessment of the Climate Change Impact 

on the Characteristic Parameters of 
Freezing in Georgia by Regions. Georgian 
Geographical Journal 2025, 5(2), 12-16. 

https://doi.org/10.52340/ggj.2025.05.02.02 



Kapanadze et al. 2025 5(2) 

13 
 

for a more nuanced understanding of how frost regimes are shifting in response to ongoing climatic 

transformations. 

Methods and Materials 

To address the research objectives, data from 26 meteorological stations of the ground observation 

network operated by the National Environmental Agency of Georgia were utilized, covering the period 

2007–2022. Based on these observational records, the frost-free periods and the dates marking the onset 

and cessation of freezing were calculated for each region. To assess the influence of climate change, 

these calculated values were compared with corresponding long-term averages derived from historical 

climate records (Handbook on the Climate of the USSR, 1967; Handbook on the Climate of the USSR, 

1971). 

Given that frosts are most pronounced under clear, calm conditions during the incursion of Arctic air 

masses from dry latitudes, it is important to consider broader climatic drivers. One such driver is the 

Arctic Oscillation (AO), a key indicator of Arctic climate variability that governs the state of 

atmospheric circulation in the high latitudes. The AO index, available from the Climate Prediction 

Center (CPC, 2025) was therefore incorporated into this analysis to explore potential links between 

global climate variability and regional frost dynamics in Georgia. 

The Arctic Oscillation refers to an atmospheric circulation pattern over the mid-to-high latitudes of 

the Northern Hemisphere, whose most notable manifestation is the latitudinal shift of the mid-latitude 

jet stream. The AO strongly influences weather and climate patterns in North America, Europe, and 

Asia, particularly during winter. 

During the AO’s positive phase, surface air pressure is lower than average over the Arctic and higher 

than average over the northern Pacific and Atlantic Oceans. This configuration shifts the jet stream 

farther north, redirecting storm tracks and generally reducing the occurrence of cold air outbreaks in the 

mid-latitudes of North America, Europe, Siberia, and East Asia. Conversely, in the AO’s negative 

phase, surface air pressure is higher than average over the Arctic and lower than average over the 

northern Pacific and Atlantic Oceans. This causes the jet stream to shift toward lower latitudes, 

facilitating the penetration of frigid polar air into the mid-latitudes and increasing the likelihood of 

severe frost events. For example, higher frequencies of coastal storms, such as Nor’easters in New 

England, have been linked to the AO’s negative phase. 

The AO index quantifies these dynamics by measuring surface atmospheric pressure anomalies at 

1000 hPa across latitudes 20° N to 90° N. These anomalies are projected onto the AO loading pattern, 

defined as the first empirical orthogonal function (EOF) of monthly mean 1000 hPa geopotential height. 

The resulting time series is normalized by the monthly standard deviation of the index. Variations in 

the AO index thus directly reflect the degree of Arctic air penetration into middle latitudes, with a 

positive AO index corresponding to stronger zonal winds that confine cold Arctic air to the polar region, 

and a negative AO index corresponding to weaker zonal winds and greater incursions of polar air into 

temperate regions. 

By comparing the AO index with frost-free period data from Georgia’s regions, this study aims to 

elucidate potential connections between large-scale atmospheric circulation patterns and local frost 

dynamics under contemporary climate change. 

Results 

In spring, advection of warm air masses from the southwest frequently occurs, often persisting for 

extended periods. This process triggers the premature termination of plant dormancy and initiates the 

onset of vegetation. However, during this transitional period, Arctic and Siberian anticyclones 

frequently invade the entire territory of Georgia from the northwest almost simultaneously. Such 

incursions result in sudden cooling and intense frosts, significantly increasing the risk of damage to 

thermophilic crops. 

The timing of plant vegetation onset and frost impacts on newly formed organs varies from year to 

year. Identifying these critical timings is essential, as they provide valuable information for predicting 

the likely dates of frost onset and cessation. This knowledge is crucial for farmers and agricultural 

practitioners to develop targeted strategies to prevent or mitigate frost-related damage. 

Table 1 presents the average dates marking the beginning and end of frost-free periods for two study 

intervals (1951–1965 and 2007–2022) across various regions of Georgia. The data reveal notable spatial 

and temporal variations. In Samegrelo, the frost-free period begins earliest (March 13 and March 1 for 

periods I and II, respectively) and ends latest (December 7 and December 23). This region is followed 



Kapanadze et al. 2025 5(2) 

14 
 

by Shida Kartli, where the average frost-free period spans from March 28 to November 21 in the first 

period and from March 16 to November 25 in the second period. Imereti and Adjara-Guria follow with 

slightly shorter frost-free durations. 

Table 1. Average dates of the beginning and end of frost-free periods 

Region 1951-1965 2007-2022  

Shida Kakheti 28 III - 21 XI 16 III - 25 XI  

Gare Kakheti 7 IV - 9 XI 27 III - 25 XI  

Shida Kartli 7 IV - 4 XI 4 IV - 8 XI  

Kvemo Kartli 17 IV - 27 X 16  IV - 30 X  

Mtskheta-Mtianeti 18 IV - 20 X 18 IV - 27 X  

Samtskhe-Javakheti 9 V - 7X 5 V - 12 X  

Imereti 1 IV - 20  XI 22 III - 5 II  

Samegrelo 13 III - 7 XII 1 III - 23 II  

Adjara-Guria 1 IV - 24 XI 26 III - 29 XI  

Racha 21 IV – 24 X 13 IV -   2 XI  

 

Conversely, the latest onset of frost-free conditions occurs in Samtskhe-Javakheti, where average 

dates for the beginning of frost-free periods are in the first decade of May (May 9 and May 5 for periods 

I and II, respectively). The frost-free period in this region ends by October 7 and October 12, yielding 

the shortest vegetation period of approximately 150–159 days. Such variations in frost-free periods 

across regions underscore the influence of local climatic conditions on agricultural cycles and highlight 

the importance of region-specific frost prediction for sustainable crop management. 

Overall, in the period 2007–2022, these shifts in frost timing have resulted in a notable increase in the 

duration of frost-free periods across most regions (Fig. 1). This pattern provides empirical evidence of 

the influence of contemporary climate change on key frost-related climatic parameters. 

It should also be noted that during the second study period (2007–2022), compared to the earlier 

period (1951–1965), the average dates of spring frosts tend to occur earlier, while autumn frosts occur 

later. This shift contributes to a general lengthening of the frost-free period. However, this trend is not 

uniform across all regions, as some local meteorological data reveal deviations. Specifically, at the 

Tsalka station in Kvemo Kartli and the Gori station in Shida Kartli, the second period records later 

average dates of spring frosts and earlier dates of autumn frosts compared to the earlier period.Fig. 2 

shows the distribution of arctic oscillation indices and the duration of frost-free periods averaged by 

region as a temperature characteristic of climate change in the territory of Georgia in the 2007-2022 

period. 

Figure 1. Change of frost-free periods according to regions 1951-1965 and between 2007-2022 



Kapanadze et al. 2025 5(2) 

15 
 

 

Discussions 

As illustrated in the figures, a pattern similar to that observed in graphs of frost-free period duration 

at individual stations (Kapanadze et al., 2023; Kapanadze et al., 2024; Kapanadze, Tatishvili et al., 

2024) is evident across the regions. Specifically, a minor phase shift is observed until approximately 

2013, after which each positive phase of the Arctic Oscillation (AO) corresponds to a relatively 

extended frost-free period (Fig. 2). This consistent relationship suggests that the climate of Georgia is, 

to a notable extent, influenced by global climate variability. 

Conclusion 

Based on the analysis of our results, it can be concluded that contemporary climate change exerts a 

discernible influence on the key parameters of freezing. This influence is manifested in shifts in the 

average dates of frost occurrence and an extension of frost-free periods, which correspond to an overall 

lengthening of the vegetation period. However, changes in the length of the growing season may have 

both positive and negative implications for crop productivity. 

An extended growing season can alter the functioning and structure of regional ecosystems, 

potentially changing the distribution of animal species, facilitating the spread of invasive plants or 

weeds, and increasing irrigation demands. Conversely, a longer warm period may offer agricultural 

benefits, enabling farmers to obtain multiple and more diverse harvests from the same plots. This could 

enhance the productivity and stability of agriculture, supporting higher and more reliable yields of crops 

in specific regions. These contrasting effects highlight the importance of region-specific strategies for 

adapting agricultural practices to evolving climatic conditions. 

Competing interests 

The authors declare that they have no competing interests. 

Authors’ contribution 

N. K. and M. T. conceived of the presented idea. I. M., A. P. performed the analytic calculations. N. 

K. and M. T. took the lead in writing the manuscript. All authors provided critical feedback and helped 

shape the research, analysis and manuscript. 

ORCID iD 

Naili Kapanadze,  http://orchid/0000-0001-7790-8867 

Marika Tatishvili  https://orcid.org/0000-0003-3327-2208 

Ana Palavandishvili http://orchid.org/0000-0002-7254-685X 

Irine Mkurnalidze http://orchid/0009-0005-5071-4225 

Figure 2. Distribution of the durations of frost-free periods averaged according to regions and Arctic Oscillation 

Indices in the territory of Georgia in the 2007-2022 period 

http://orchid/0000-0001-7790-8867
https://orcid.org/0000-0003-3327-2208
http://orchid.org/0000-0002-7254-685X
http://orchid/0009-0005-5071-4225


Kapanadze et al. 2025 5(2) 

16 
 

 

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