The submarine hydrothermal activity on and near the Galápagos Rift has been explored with the aid of the deep submersible Alvin. Analyses of water samples from hydrothermal vents reveal that hydrothermal activity provides significant or dominant sources and sinks for several components of seawater; studies of conductive and convective heat transfer suggest that two-thirds of the heat lost from new oceanic lithosphere at the Galápagos Rift in the first million years may be vented from thermal springs, predominantly along the axial ridge within the rift valley. The vent areas are populated by animal communities. They appear to utilize chemosynthesis by sulfur-oxidizing bacteria to derive their entire energy supply from reactions between the seawater and the rocks at high temperatures, rather than photosynthesis.

The concentration of atmospheric carbon dioxide at Mauna Loa Observatory, Hawaii is reported for eight years (1964–1971) of a long term program to document the effects of the combustion of coal, petroleum, and natural gas on the distribution of CO2 in the atmosphere. The new data, when combined with earlier data, indicate that the annual average CO2 concentration rose 3.4% between 1959 and 1971. The rate of rise, however, has not been steady. In the mid‐1960's it declined. Recently it has accelerated. Similar changes in rate have been observed at the South Pole and are evidently a global phenomenon.

The concentration of atmospheric carbon dioxide at Mauna Loa Observatory, Hawaii is reported for eight years (1964)(1965)(1966)(1967)(1968)(1969)(1970)(1971)) of a long term program to document the effects of the combustion of coal, petroleum, and natural gas on the distribution of CO, in the atmosphere. The new data, when combined with earlier data, indicate that the annual average CO, concentration rose 3.4 ' % between 1959 and 1971. The rate of rise, however, has not been steady. In the mid-1960's it declined. Recently i t has accelerated. Similar changes in rate have been observed at the South Pole and are evidently a global phenomenon.

During the Geosecs expedition in the Atlantic and the Pacific oceans, more than 100 stations were occupied for the measurement of surface radon profiles. The radon deficiency in these profiles gives estimates of the gas transfer rate across the sea‐air interface. The global mean transfer rate is estimated to be 2.9 m/d (at 20°C) which is corresponding to a hypothetical stagnant film thickness of about 36 microns. No clear relationship can be found between the gas exchange rate and wind speed. The CO2 exchange rate as determined by the radon method is 80% of that given by the distributions of natural and of bomb‐produced radiocarbon. One possible explanation may be that the Geosecs radon measurements were made during periods of lower than average wind speed. Another is that the conversion of CO2 to HCO3− is catalyzed within the sea.

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