Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Site Tools

  • AAAS
  • Subscribe
  • Feedback

Site Search

Search Advanced

Originally published in Science Express on 21 June 2007
Science 27 July 2007:
Vol. 317. no. 5837, pp. 478 - 482
DOI: 10.1126/science.1142834
Prev | Table of Contents | Next

Research Articles

Free-Drifting Icebergs: Hot Spots of Chemical and Biological Enrichment in the Weddell Sea

Kenneth L. Smith, Jr.,1* Bruce H. Robison,1 John J. Helly,2 Ronald S. Kaufmann,3 Henry A. Ruhl,1 Timothy J. Shaw,4 Benjamin S. Twining,4 Maria Vernet5

The proliferation of icebergs from Antarctica over the past decade has raised questions about their potential impact on the surrounding pelagic ecosystem. Two free-drifting icebergs, 0.1 and 30.8 square kilometers in aerial surface area, and the surrounding waters were sampled in the northwest Weddell Sea during austral spring 2005. There was substantial enrichment of terrigenous material, and there were high concentrations of chlorophyll, krill, and seabirds surrounding each iceberg, extending out to a radial distance of ~3.7 kilometers. Extrapolating these results to all icebergs in the same size range, with the use of iceberg population estimates from satellite surveys, indicates that they similarly affect 39% of the surface ocean in this region. These results suggest that free-drifting icebergs can substantially affect the pelagic ecosystem of the Southern Ocean and can serve as areas of enhanced production and sequestration of organic carbon to the deep sea.

1 Monterey Bay Aquarium Research Institute (MBARI), 7700 Sandholdt Road, Moss Landing, CA 95039, USA.
2 San Diego Supercomputer Center, University of California, San Diego, La Jolla, CA 92093–0505, USA.
3 Marine Science and Environmental Studies Department, University of San Diego, 5998 Alcalá Park, San Diego, CA 92110, USA.
4 Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208, USA.
5 Integrative Oceanography Division, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92093–0218, USA.

* To whom correspondence should be addressed. E-mail: ksmith{at}mbari.org

Read the Full Text


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Nanogeoscience: From Origins to Cutting-Edge Applications.
M. F. Hochella Jr (2008)
Elements 4, 373-379
   Abstract »    Full Text »    PDF »
Nanominerals, Mineral Nanoparticles, and Earth Systems.
M. F. Hochella Jr., S. K. Lower, P. A. Maurice, R. L. Penn, N. Sahai, D. L. Sparks, and B. S. Twining (2008)
Science 319, 1631-1635
   Abstract »    Full Text »    PDF »
Nanoparticulate bioavailable iron minerals in icebergs and glaciers.
R. Raiswell, L. G. Benning, L. Davidson, and M. Tranter (2008)
Mineralogical Magazine 72, 345-348
   Abstract »    Full Text »    PDF »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)