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Microbiological studies in Stirling Basin, Milford Sound
Oceanographic Abstracts
1061
tion o f whale stocks does not make very good economic sense. Yet, not only has international agreement so far failed to prevent irresponsible over-exploitation of this valuable and irreplaceable natural resource, but the whaling industry itself has entirely failed to look to the future and to plan longterm operations in the light o f the scientific evidence available to it. Adoption by the commission of the recommendations o f its own scientific advisers would involve no surrender to sentiment but would provide a blueprint both for ensuring the continuance o f whale stocks and for securing the whaling industry's own means of existence. The unrestricted slaughter which resulted in the near-extermination of whales in the Northern Hemisphere during the last century could be in part excused on grounds of ignorance. That excuse is no longer valid, yet an identical result is now likely to be achieved quite deliberately---even, apparently, at the cost o f self-destruction of the industry. SIMPSON JOANNE, ROBERT H. SIMPSON, DONALD A. ANDREWS and MAX A. EATON, 1965. Experimental cumulus dynamics. Reviews of Geophysics, 3 (3): 387~31. Cumulus dynamics is approached as an experimental science. Its development since 1947 is briefly reviewed and the current convection models described, in particular models evolved from laboratory studies, such as the " s t a r t i n g plume." A preliminary series of experiments on real tropical cumuli has been conducted as a method for testing and improving models and for assessing the range of applicability of the laboratory results. A silver iodide seeding technique was used in a joint U.S. Weather Bureau-U.S. Navy experimental program called Project Stormfury. Eleven tropical cumulus clouds were probed by instrumented aircraft on four days in August 1963. Six were seeded by dropping pyrotechnic silver iodide generators into their tops at intervals of 100 meters or less; five were studied as " c o n t r o l s . " All control clouds died without further growth. Of the treated clouds, one was seeded by misunderstanding when its top was below 10,000 feet, it collapsed. The remaining five treated clouds grew. Of these, three were seeded at low enough elevations so that natural glaciation was unlikely; these are called the " test " clouds. All three test clouds were observed t o " e x p l o d e " in two phases. The first phase was a vertical growth of 10,000-20,000 ft, occupying 10-12 minutes; the second was a horizontal expansion, with the resulting giant cloud persisting more than 30 minutes. Using laboratory and theoretical results, we construct a dynamic model of the first growth phase and test it against the aircraft measurements and photographic data. The model predicts tower ascent rates, excess temperatures, and water contents, with environment and cloud base conditions as input. It predicts that unmodified clouds could not have attained the observed heights. Furthermore, the postulated effects of seeding (fusion heating, expansion, and altered precipitation fallout) are incorporated into the model and are shown able to account for the excessive growth of the test clouds following treatment. A set of extensive control calculations shows that the main deductions are insensitive to the existing uncertainties in the input data and the modeling assumptions. Improved experiments are suggested to resolve some of the basic questions in cumulus dynamics, as well as seeding effects. SKERMAN T. M., 1964. Microbiological studies in Stirling Basin, Milford Sound. New Zealand Dept. Sci. Ind. Res., Bull., No. 157: New Zealand Oceanogr. lnst., Memoir, No. 17: 65-71. The waters o f Stifling Basin, Milford Sound, support an abundant heterotrophic bacterial population that is indicative o f their high content o f organic matter, most of which is probably terrigenous in origin. Aerobes outnumbered anaerobes throughout the water column, whereas in the sediments, the converse situation was apparent. Sulphate-reducing bacteria were observed at all sampled depths of sediments, which were generally o f - v e Eh, but only in the bottommost Basin waters. All attempts to isolate photosynthetic purple or green sulphur bacteria (Thiorhodaceae) from Basin waters failed. Thiobacilli were isolated only from surface sediments where oxygenated waters overlay muds in which hydrogen sulphide was being liberated. On the whole, the microbiological data is consistent with the hydrological findings that at the time o f sampling, the Basin waters were oxygenated throughout. Based o n published figures on oxygen uptake by multiplying marine bacteria and a mean aerobic bacterial density in the water, a figure for the overall bacterial oxygen uptake has been estimated at 13-1 ml oxygen per litre per year. This uptake due to bacterial oxidative processes in the water would require to be balanced by replenishment processes in order to prevent complete oxygen depletion below sill depth. The above figure includes neither the oxygen consumption by bacteria in the sediments, nor the respiratory activities of the benthic and pelagic fauna. On the other hand, if the organic material undergoing decomposition in Stirling Basin is of a refractory nature, it would contribute to a lower biochemical oxygen demand than the figure indicates. SKOPt~rrsEv B. A., 1965. Investigation of the oxygen minimum layer in the North Atlantic during the autumn o f 1959. (In Russian; English abstract). Okeanol. lssled. Rezult. lssled. Programme Mezhd. Geofiz. Goda. Mezhd. Geofiz. Komitet. Presidiume Akad. Nauk. SSSR, No. 13:108-114. Based o n data collected abroad by the R/V M. Lomonosov and on some previous cruises conditions were considered for the formation of the oxygen minimum layer in the tropical North Atlantic off the African Coast. In the open ocean there is no obvious indication o f the processes which cause such a minimum. It is therefore to be supposed that the existence o f the oxygen minimum layer in the open ocean first o f all results from the penetration o f waters carried there by the trade wind current from the eastern part o f the ocean.
1061
tion o f whale stocks does not make very good economic sense. Yet, not only has international agreement so far failed to prevent irresponsible over-exploitation of this valuable and irreplaceable natural resource, but the whaling industry itself has entirely failed to look to the future and to plan longterm operations in the light o f the scientific evidence available to it. Adoption by the commission of the recommendations o f its own scientific advisers would involve no surrender to sentiment but would provide a blueprint both for ensuring the continuance o f whale stocks and for securing the whaling industry's own means of existence. The unrestricted slaughter which resulted in the near-extermination of whales in the Northern Hemisphere during the last century could be in part excused on grounds of ignorance. That excuse is no longer valid, yet an identical result is now likely to be achieved quite deliberately---even, apparently, at the cost o f self-destruction of the industry. SIMPSON JOANNE, ROBERT H. SIMPSON, DONALD A. ANDREWS and MAX A. EATON, 1965. Experimental cumulus dynamics. Reviews of Geophysics, 3 (3): 387~31. Cumulus dynamics is approached as an experimental science. Its development since 1947 is briefly reviewed and the current convection models described, in particular models evolved from laboratory studies, such as the " s t a r t i n g plume." A preliminary series of experiments on real tropical cumuli has been conducted as a method for testing and improving models and for assessing the range of applicability of the laboratory results. A silver iodide seeding technique was used in a joint U.S. Weather Bureau-U.S. Navy experimental program called Project Stormfury. Eleven tropical cumulus clouds were probed by instrumented aircraft on four days in August 1963. Six were seeded by dropping pyrotechnic silver iodide generators into their tops at intervals of 100 meters or less; five were studied as " c o n t r o l s . " All control clouds died without further growth. Of the treated clouds, one was seeded by misunderstanding when its top was below 10,000 feet, it collapsed. The remaining five treated clouds grew. Of these, three were seeded at low enough elevations so that natural glaciation was unlikely; these are called the " test " clouds. All three test clouds were observed t o " e x p l o d e " in two phases. The first phase was a vertical growth of 10,000-20,000 ft, occupying 10-12 minutes; the second was a horizontal expansion, with the resulting giant cloud persisting more than 30 minutes. Using laboratory and theoretical results, we construct a dynamic model of the first growth phase and test it against the aircraft measurements and photographic data. The model predicts tower ascent rates, excess temperatures, and water contents, with environment and cloud base conditions as input. It predicts that unmodified clouds could not have attained the observed heights. Furthermore, the postulated effects of seeding (fusion heating, expansion, and altered precipitation fallout) are incorporated into the model and are shown able to account for the excessive growth of the test clouds following treatment. A set of extensive control calculations shows that the main deductions are insensitive to the existing uncertainties in the input data and the modeling assumptions. Improved experiments are suggested to resolve some of the basic questions in cumulus dynamics, as well as seeding effects. SKERMAN T. M., 1964. Microbiological studies in Stirling Basin, Milford Sound. New Zealand Dept. Sci. Ind. Res., Bull., No. 157: New Zealand Oceanogr. lnst., Memoir, No. 17: 65-71. The waters o f Stifling Basin, Milford Sound, support an abundant heterotrophic bacterial population that is indicative o f their high content o f organic matter, most of which is probably terrigenous in origin. Aerobes outnumbered anaerobes throughout the water column, whereas in the sediments, the converse situation was apparent. Sulphate-reducing bacteria were observed at all sampled depths of sediments, which were generally o f - v e Eh, but only in the bottommost Basin waters. All attempts to isolate photosynthetic purple or green sulphur bacteria (Thiorhodaceae) from Basin waters failed. Thiobacilli were isolated only from surface sediments where oxygenated waters overlay muds in which hydrogen sulphide was being liberated. On the whole, the microbiological data is consistent with the hydrological findings that at the time o f sampling, the Basin waters were oxygenated throughout. Based o n published figures on oxygen uptake by multiplying marine bacteria and a mean aerobic bacterial density in the water, a figure for the overall bacterial oxygen uptake has been estimated at 13-1 ml oxygen per litre per year. This uptake due to bacterial oxidative processes in the water would require to be balanced by replenishment processes in order to prevent complete oxygen depletion below sill depth. The above figure includes neither the oxygen consumption by bacteria in the sediments, nor the respiratory activities of the benthic and pelagic fauna. On the other hand, if the organic material undergoing decomposition in Stirling Basin is of a refractory nature, it would contribute to a lower biochemical oxygen demand than the figure indicates. SKOPt~rrsEv B. A., 1965. Investigation of the oxygen minimum layer in the North Atlantic during the autumn o f 1959. (In Russian; English abstract). Okeanol. lssled. Rezult. lssled. Programme Mezhd. Geofiz. Goda. Mezhd. Geofiz. Komitet. Presidiume Akad. Nauk. SSSR, No. 13:108-114. Based o n data collected abroad by the R/V M. Lomonosov and on some previous cruises conditions were considered for the formation of the oxygen minimum layer in the tropical North Atlantic off the African Coast. In the open ocean there is no obvious indication o f the processes which cause such a minimum. It is therefore to be supposed that the existence o f the oxygen minimum layer in the open ocean first o f all results from the penetration o f waters carried there by the trade wind current from the eastern part o f the ocean.