Georgia’s climate is affected by subtropical influences from the west and Mediterranean influences from the east. The Greater Caucasus range moderates local climate by serving as a barrier against cold air from the north. Warm, moist air from the Black Sea moves easily into the coastal lowlands from the west. Climatic zones are determined by distance from the Black Sea and by altitude. Along the Black Sea coast, from Abkhazia to the Turkish border, and in the region known as the Kolkhida Lowlands inland from the coast, the dominant subtropical climate features high humidity and heavy precipitation (1,000 to 2,000 mm/39.4 to 78.7 in per year; the Black Sea port of Batumi receives 2,500 mm/98.4 in per year). Several varieties of palm trees grow in these regions, where the midwinter average temperature is 5 °C (41 °F) and the midsummer average is 22 °C (71.6 °F).
The plains of eastern Georgia are shielded from the influence of the Black Sea by mountains that provide a more continental climate. Summer temperatures average 20 °C (68 °F) to 24 °C (75.2 °F), winter temperatures 2 °C (35.6 °F) to 4 °C (39.2 °F). Humidity is lower, and rainfall averages 500 to 800 mm (19.7 to 31.5 in) per year. Alpine and highland regions in the east and west, as well as a semi-arid region on the Iori Plateau to the southeast, have distinct microclimates.
At higher elevations, precipitation is sometimes twice as heavy as in the eastern plains. In the west, the climate is subtropical to about 650 m (2,133 ft); above that altitude (and to the north and east) is a band of moist and moderately warm weather, then a band of cool and wet conditions. Alpine conditions begin at about 2,100 m (6,890 ft), and above 3,600 m (11,811 ft) snow and ice are present year-round.
Beginning in the 1980s, Black Sea pollution has greatly harmed Georgia’s tourist industry. Inadequate sewage treatment is the main cause of that condition. In Batumi, for example, only 18 percent of wastewater is treated before release into the sea. An estimated 70 percent of surface water contains health-endangering bacteria to which Georgia’s high rate of intestinal disease is attributed.
The war in Abkhazia did substantial damage to the ecological habitats unique to that region. In other respects, experts considered Georgia’s environmental problems less serious than those of more industrialized former Soviet republics. Solving Georgia’s environmental problems was not a high priority of the national government in the post-Soviet years, however; in 1993 the minister for protection of the environment resigned to protest this inactivity. In January 1994, the Cabinet of Ministers announced a new, interdepartmental environmental monitoring system to centralize separate programs under the direction of the Ministry of Protection of the Environment. The system would include a central environmental and information and research agency. The Green Party used its small contingent in the parliament to press environmental issues in 1993.
Georgia participates in a number of international environmental agreements. It is a party to: Air Pollution, Biodiversity, Climate Change, Climate Change-Kyoto Protocol, Desertification, Endangered Species, Hazardous Wastes, Law of the Sea, Ozone Layer Protection, and Ship Pollution, Wetlands.