Iron and DOC Studies in the Wor1d Ocean.

• Main Author: Martin, John H.
• Other Authors: MOSS LANDING MARINE LABS CA
• Format: Text
• Language: English
• Published: 1991
• Subjects: Atmospheric Physics; Biological Oceanography; Air Pollution and Control; *IRON; *PLANT GROWTH; *CARBON DIOXIDE; *GREENHOUSE EFFECT; *PHYTOPLANKTON; AIR POLLUTION; HIGH TEMPERATURE; DEFICIENCIES; SURFACE WATERS; PERTURBATIONS; PRODUCTIVITY; ENVIRONMENTAL PROTECTION; OCEAN ENVIRONMENTS; ANTARCTIC REGIONS; FOSSIL FUELS; SURFACE TO AIR; ATMOSPHERIC CHEMISTRY; TRACE ELEMENTS; 14; Antarctic; Antarc*
• Online Access: http://www.dtic.mil/docs/citations/ADA289064; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA289064

There is a great deal of concern about the ever-increasing concentration of carbon dioxide in the atmosphere and it is generally acknowledged that the resulting greenhouse effect will cause higher global temperatures and changes in the earth's climate. During the last 100 years, expanding industrialization and fossil fuel burning have brought the CO2 level to approx. 355 ppm, a value subtantially higher than any observed in recent geological history. Analyses of ancient air trapped in Antarctic ice indicate that C02 amounts have varied over the last 160,000 years from a low of approx. 200 ppm during the ice ages (glacials) to a high of approx. 280 ppm during the warm periods between the ice ages (interglacials). If we could better understand the reasons for these natural variations in atmospheric CO2 concentrations, we would be in a better position to forecast changes brought about by man's perturbation of the environment. Although the factors responsible for the glacial/interglacial changes in CO2 levels are not understood, it is thought that oceanic processes are responsible since the ocean contains an equivalent of 60 times as much CO2 as that in the atmosphere. Many also believe that changes in the functioning of the ocean 'biological pump' --phytoplankton growth in surface waters with photosynthetic uptake of CO2 and sinking away of carbon-rich plant remains from the surface to deep ocean -- played a dominant role in bringing about the changes in glacial/interglacial atmospheric CO2 levels. Our research is directly related to this problem in two ways: