Seasonal study of carbon dioxide in the southern extreme of the pacific sector, Antarctic Ocean. Progress report Page: 6 of 16
This report is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided to UNT Digital Library by the UNT Libraries Government Documents Department.
Extracted Text
The following text was automatically extracted from the image on this page using optical character recognition software:
i
-4-
At 35 stations where the CO2 properties in seawater were measured, particulate carbon
samples were also collected by filtration by Andrew McTaggart. These samples will be used by
John Hayes and his colleagues of Indiana University to investigate the relationships between the
CO2 concentration in seawater and 3C/2C ratios in specific organic compounds produced by
photosynthesis.
3. OCEANOGRAPHIC CONDITIONS
It is of interest to know general oceanographic and ice conditions in the southern extreme
of the Pacific Ocean during the expedition. The following is reproduced from the Chief Scientist's
CrmIse Report for NBP94-02 prepared by Stanley S. Jacobs (1994).
"Both the sea and glacial ices are extraordinary in the Amundsen and Bellingshause Seas,
with a wide diversity in new sea ice forms and old iceberg shapes. Heterogeneous mixtures of old
and new ice floes were very common, along with ample evidence of snow ice formation. Most floes
thicker than 15 cm were rotten at the base, in part because of the late-summer Eason. However,
the warm water on the shelf must effectively limit sea ice growth from below, particularly in areas
where this water shoals due to offshore winds. In addition to this, the absence of newly-formed
shelf water also implies a strong and perhaps dominant sensible heat component in the coastal
polynyas."
"Nowhere else have we seen so many icebergs, and they were often grounded and
surrounded by close or fast ice. This grounding, in combination with prevailing light easterly and
northerly winds, must contribute to a generally sluggish ocean circulation on the continental shelf.
It may also play a role in the maintenance of some of the open water aloug the coastline, in
particular the Amundsen Polynya. Several CTD casts were made during a circumnavigation of the
world's oldest and largest iceberg, B-10, which is grounded on the floor of the Amundsen shelf.
Most of its perimeter appears to be afloat, and at these locations the basal melting must be of the
order of a few meters per year. However, the high surface accumulation rate in this sector may
help to keep many of the bergs well-grounded on the shelf, leading to a lengthy residence time."
"One feature that is not well-developed in this region is the Antarctic Slope Front.
Indications of a weak front were encountered at some slope crossings, but nothing compare with
the strong fronts in the Ross and Weddell Seas. We did observe evidence of upwelling north of the
shelf, where the surface layers are substantially thinner than over the slope and shelf. Most of the
Upcoming Pages
Here’s what’s next.
Search Inside
This report can be searched. Note: Results may vary based on the legibility of text within the document.
Tools / Downloads
Get a copy of this page or view the extracted text.
Citing and Sharing
Basic information for referencing this web page. We also provide extended guidance on usage rights, references, copying or embedding.
Reference the current page of this Report.
Takahashi, Taro; Goddard, J. G.; Rubin, S. I. & Breger, D. Seasonal study of carbon dioxide in the southern extreme of the pacific sector, Antarctic Ocean. Progress report, report, May 5, 1994; United States. (https://digital.library.unt.edu/ark:/67531/metadc1341008/m1/6/: accessed May 9, 2024), University of North Texas Libraries, UNT Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.