ABSTRACT
Although approximately 70% of the Earth's surface is covered by water, freshwater makes up only 3% of the total water on the planet. The majority of freshwater is stored as ice in glaciers and polar ice sheets. Although humans rely heavily on freshwater from rivers and lakes, this surface water amounts to only 0.02% of all water on Earth. Most liquid freshwater is stored in aquifers as groundwater. Still, groundwater makes up only 1% of all water on the planet. Groundwater can be viewed as a product of climate. This is because the groundwater available for use is deposited by atmospheric precipitation. Changes in climate will then inevitably affect groundwater, its resources, and quality. Publications discussing this problem are numerous, dissimilar, and contradictory; however, the effects of climate changes on groundwater have only been discussed in a limited manner. Geological science has demonstrated continuous climate change throughout the history of Earth. Changes developed both slowly and relatively quickly in the geological time scale. Past climatic changes have been caused by changes in solar activity, meteorite showers, variations in Earth's axis position, volcanic activity, and a wide array of other natural activities, which caused changes in the Earth's albedo and the greenhouse effect of the atmosphere. Figure 31.1 presents a schematic flowchart showing a relationship between climate change and loss of fresh groundwater in coastal aquifers.
