Green icebergs formed by freezing of organic-rich seawater to the base of Antarctic ice shelves
Samples of Antarctic seawater, basal ice, and green ice from ice cliffs and green icebergs are analyzed in order to examine green icebergs formed by the freezing of organic-rich seawater to the base of Antarctic ice shelves. Spectral reflectance of a green iceberg measured near 67 deg S, 62 deg E co...
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ftnasantrs:oai:casi.ntrs.nasa.gov:19930051759 2023-05-15T13:22:07+02:00 Green icebergs formed by freezing of organic-rich seawater to the base of Antarctic ice shelves Warren, Stephen G. Roesler, Collin S. Morgan, Vincent I. Brandt, Richard E. Goodwin, Ian D. Allison, Ian Unclassified, Unlimited, Publicly available April 15, 1993 http://ntrs.nasa.gov/search.jsp?R=19930051759 unknown http://ntrs.nasa.gov/search.jsp?R=19930051759 Accession ID: 93A35756 Copyright Other Sources 48 Journal of Geophysical Research; 98; C4; p. 6921-6928. 1993 ftnasantrs 2012-02-15T20:07:35Z Samples of Antarctic seawater, basal ice, and green ice from ice cliffs and green icebergs are analyzed in order to examine green icebergs formed by the freezing of organic-rich seawater to the base of Antarctic ice shelves. Spectral reflectance of a green iceberg measured near 67 deg S, 62 deg E confirms that the color is inherent in the ice, not an artifact of the illumination. A constituent that absorbs blue photons is identified by spectrophotometric analysis of core samples from this iceberg and from the Amery basal ice, and of seawater samples from Prydz Bay off the Amery Ice Shelf. Analysis of the samples by fluorescence spectroscopy indicates that the blue absorption, and hence the inherent green color, is due to the presence of marine-derived organic matter in the green iceberg, basal ice, and seawater. Thick accumulations of green ice, in icebergs, and at the base of ice shelves indicate that high concentrations of organic matter exist in seawater for centuries at the depth of basal freezing. Other/Unknown Material Amery Ice Shelf Antarc* Antarctic Ice Shelf Ice Shelves Iceberg* Prydz Bay NASA Technical Reports Server (NTRS) Antarctic Prydz Bay Amery ENVELOPE(-94.063,-94.063,56.565,56.565) Amery Ice Shelf ENVELOPE(71.000,71.000,-69.750,-69.750) |
institution |
Open Polar |
collection |
NASA Technical Reports Server (NTRS) |
op_collection_id |
ftnasantrs |
language |
unknown |
topic |
48 |
spellingShingle |
48 Warren, Stephen G. Roesler, Collin S. Morgan, Vincent I. Brandt, Richard E. Goodwin, Ian D. Allison, Ian Green icebergs formed by freezing of organic-rich seawater to the base of Antarctic ice shelves |
topic_facet |
48 |
description |
Samples of Antarctic seawater, basal ice, and green ice from ice cliffs and green icebergs are analyzed in order to examine green icebergs formed by the freezing of organic-rich seawater to the base of Antarctic ice shelves. Spectral reflectance of a green iceberg measured near 67 deg S, 62 deg E confirms that the color is inherent in the ice, not an artifact of the illumination. A constituent that absorbs blue photons is identified by spectrophotometric analysis of core samples from this iceberg and from the Amery basal ice, and of seawater samples from Prydz Bay off the Amery Ice Shelf. Analysis of the samples by fluorescence spectroscopy indicates that the blue absorption, and hence the inherent green color, is due to the presence of marine-derived organic matter in the green iceberg, basal ice, and seawater. Thick accumulations of green ice, in icebergs, and at the base of ice shelves indicate that high concentrations of organic matter exist in seawater for centuries at the depth of basal freezing. |
format |
Other/Unknown Material |
author |
Warren, Stephen G. Roesler, Collin S. Morgan, Vincent I. Brandt, Richard E. Goodwin, Ian D. Allison, Ian |
author_facet |
Warren, Stephen G. Roesler, Collin S. Morgan, Vincent I. Brandt, Richard E. Goodwin, Ian D. Allison, Ian |
author_sort |
Warren, Stephen G. |
title |
Green icebergs formed by freezing of organic-rich seawater to the base of Antarctic ice shelves |
title_short |
Green icebergs formed by freezing of organic-rich seawater to the base of Antarctic ice shelves |
title_full |
Green icebergs formed by freezing of organic-rich seawater to the base of Antarctic ice shelves |
title_fullStr |
Green icebergs formed by freezing of organic-rich seawater to the base of Antarctic ice shelves |
title_full_unstemmed |
Green icebergs formed by freezing of organic-rich seawater to the base of Antarctic ice shelves |
title_sort |
green icebergs formed by freezing of organic-rich seawater to the base of antarctic ice shelves |
publishDate |
1993 |
url |
http://ntrs.nasa.gov/search.jsp?R=19930051759 |
op_coverage |
Unclassified, Unlimited, Publicly available |
long_lat |
ENVELOPE(-94.063,-94.063,56.565,56.565) ENVELOPE(71.000,71.000,-69.750,-69.750) |
geographic |
Antarctic Prydz Bay Amery Amery Ice Shelf |
geographic_facet |
Antarctic Prydz Bay Amery Amery Ice Shelf |
genre |
Amery Ice Shelf Antarc* Antarctic Ice Shelf Ice Shelves Iceberg* Prydz Bay |
genre_facet |
Amery Ice Shelf Antarc* Antarctic Ice Shelf Ice Shelves Iceberg* Prydz Bay |
op_source |
Other Sources |
op_relation |
http://ntrs.nasa.gov/search.jsp?R=19930051759 Accession ID: 93A35756 |
op_rights |
Copyright |
_version_ |
1766363341476855808 |