Information Encoded into Water During the Hydrological Cycle

3 Information Encoded into Water During the Hydrological Cycle 

Wind carries water droplets of seawater which dry and form salt grains. These windborne salts, or sea spray, reach the clouds and are carried along with them. Sea spray also reaches the continents as aerosols that settle on surfaces and are washed into the ground by rain. 

Rainwater dissolves atmospheric N2 and 02 and the rare gases as well as C02. In addition, radioactive tritium, 14C, and 36C1 are incorporated into the hydrological cycle and reach groundwater. 

Manmade pollutants reach rainwater through the air. The best known is acid rain, which contains sulfur compounds. A large variety of other pollutants of urban life and industry are lifted into the atmosphere and washed down by rain. As clouds move inland or rise up mountains, their water condenses and gradually rains out. Isotopic fractionation increases the deuterium and lsO content of the condensed rain, depleting the concentration of these isotopes in the vapor remaining in the cloud. As the cloud moves on into the continent or up a mountain, the rain produced becomes progressively depleted in the heavy isotopes. Surveys have been developed into a source of information on distance of recharge from the 

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