Antarctica, area

Anthropogenic emissions cause the depletion of the ozone. This is generally known through reports on the hole in the ozone layer. Although these reports referred only to the Antarctica area, ozone depletion is now also discernible to a lower degree on the mid-latitudes (e.g. Europe). 

A detailed analysis of the atmospheric measurements over Antarctica by Anderson et al. (19) indicates that the cycle comprising reactions 17 -19 (the chlorine peroxide cycle) accounts for about 75% of the observed ozone depletion, and reactions 21 - 23 account for the rest. While a clear overall picture of polar ozone depletion is emerging, much remains to be learned. For example, the physical chemistry of the acid ices that constitute polar stratospheric clouds needs to be better understood before reliable predictions can be made of future ozone depletion, particularly at northern latitudes, where the chemical changes are more subtle and occur over a larger geographical area. 

Consequences of Ozone Depletion. Ozone depletion over Antarctica is causing renewed concern about the consequences of increased levels of UV reaching the earth s biosphere. One area of concern involves the free-floating microscopic plants, known collectively as phytoplankton (the grass of the sea), which through the process of photosynthesis, fix carbon dioxide into living organic matter. Phytoplankton forms the basis of the marine food chain on which zooplankton (animal plankton) and all other components of the ecosystem depend for their sustenance. 

There is an agreement that a hole (really a thin area) in the ozone layer over the Earth s polar regions, particularly Antarctica, changes in size over periods of time. The ozone is produced over the tropics and spreads to the polar areas. But not all scientists agree on the associated causes, seriousness, dangers involved, and remedies. 

The ozone layer is dynamic and unpredictable, which means it is constantly changing and seems to change in ways we cannot yet understand. The large thin area (hole) over Antarctica seems not only to move hut also to become larger and then smaller. The ozone layer is thickest over the poles of the Earth, yet it is mostly produced over the equator. 

Additionally, in two different monitoring campaigns conducted in the center of Milan, Italy, Ciccioli and co-workers (1993) reported 2-nitrofluoranthene, 2-nitropyrene, and 1-nitropyrene were the only ni-troarenes detected. Subsequently, in a comprehensive study of the atmospheric formation and transport of 2-nitrofluoranthene and 2-nitropyrene, they established their presence and levels in ambient particles collected at sites located in urban, suburban, forest, and remote areas in Europe, Asia, America, and Antarctica (Ciccioli et al., 1996, and references therein see also Ciccioli et al., 1995). 

About the same time that meteorites were found in Antarctica, an important collection of meteorites was being put together in Roosevelt County, New Mexico. Over a period from 1966 to 1972, several meteorite hunters collected 140 meteorite specimens representing about 100 separate fall events. This collection demonstrated another way for nature to concentrate meteorites. The meteorites in Roosevelt County were found in blowout areas where up to a meter of soil had been blown away by wind, leaving meteorites in plain view on the hardpan surface. Based on this experience, systematic and successful searches of desert areas in Western Australia have been carried out. Subsequently, the deserts of North Africa have turned out to be especially prolific sources of meteorites. The shifting desert sands expose meteorites that have accumulated over thousands of years. The meteorites are collected by nomads and sold to western collectors. Although most desert meteorites are weathered to some degree, new and rare meteorite classes have been discovered. 

The Apollo astronauts returned 382 kg of lunar sample to Earth, and this collection was supplemented by 326 g of soil samples collected by the Soviet Luna landers. The first lunar meteorite was found in 1982 in Antarctica. Since that time, over 120 lunar meteorites representing about 60 different fall events have been collected. The total mass of these meteorites is -48 kg. About one-third of these meteorites were recovered in Antarctica by American and Japanese teams, and most of the rest were recovered in the deserts of North Africa and Oman. The lunar meteorites have significantly expanded the areas of the Moon from which we have samples. 

Large areas underlain by coal probably are present all along the mountainous margin of the Antarctic plateau which stretches clear across Antarctica. Only the Amery deposit and that of the Sentinel Mountains occur outside this Transantarctic Mountain area. 

Queen Maud Range, Thorvald Nilson Mts. (86°7 S., 150°8 W.), Antarctica, Upper Amundsen Glacier area, about 955 ft. above basement contact. Section 7, QM 147 Coll. Jan. 1964, W. E. Long, OSU. 

Figure 1. Map of Antarctica showing the general area of coal sample localities...

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