Variations in mercury deposition to Antarctica over the past 34,000 years
Article Abstract:
Atmospheric mercury deposition to the Antarctic ice cap in the past 34,000 years was examined using stringent trace metal-cleaning methods. The results showed that mercury concentrations were significantly elevated about 18,000 years ago, during the last glacial maximum which was characterized by high oceanic productivity. The results suggest that oceanic productivity is the main pre-industrial source of Antarctic mercury. Aside from serving as a paleoproductivity indicator, the results also provide a baseline for studying recent anthropogenic mercury emissions.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1993
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Ozone clouds over the Atlantic
Article Abstract:
New measurements taken on airline jets indicate that air pockets of extremely high ozone concentration are in some manner entering from the stratosphere to the troposphere over the tropical Atlantic. Normally, about 90% of all ozone is situated in the stratosphere, which is that part of the Earth's atmosphere above 10-20 kilometers from the ground, and 10% is located in the troposphere, which is the region immediately below the stratosphere extending down to ground level. Ozone and ultraviolet radiation in the troposphere have numerous negative implications.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1997
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Meteoric smoke fallout over the Holocene epoch revealed by iridium and platinum in Greenland ice
Article Abstract:
A record of iridium and platinum fluxes on a climatic-cycle timescale, back to 128,000 years ago, from a Greenland ice core, is reported. It is stated that unexpectedly constant fallout of extraterrestrial matter to Greenland occurred during the Holocene, whereas a greatly enhanced input of terrestrial iridium and platinum masked the cosmic flux in the dust-laden atmosphere of the last glacial age.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2004
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