Antarctic Journal of the United States Review 1997, Table of contents |
During the 1996-1997 austral summer and the 1997 winter, approximately 640 scientists and other specialists conducted 145 research projects in Antarctica under the auspices of the U.S. Antarctic Program. Supported by the National Science Foundation (NSF), they worked at McMurdo Station on Ross Island, at field camps in numerous locations, at Amundsen-Scott South Pole Station, aboard the ice-capable research ships Polar Duke and Nathaniel B. Palmer, and at Palmer Station on Anvers Island.
Although not every research grant is covered
here, the projects described in this issue of the Antarctic Journal
are intended to provide a representative overview of the U.S. Antarctic
Research Program. In addition to the science teams working in Antarctica,
researchers in the United States analyzed data acquired during fieldwork.
This issue, comprised of 89 new papers prepared by program participants
and seven articles that originally appeared in the 1997 monthly online
issues of the journal, reflects the breadth of the U.S. program. Although
final results typically will appear in peer-reviewed scientific journals,
the Antarctic Journal , which is not peer-reviewed, is intended
to provide initial reports. The assistance of all who contributed is gratefully
acknowledged.
Between November 1996 and February 1997, the AMANDA team installed six new strings of optical detectors, bringing the total for AMANDA-B to ten 2-kilometer-long strings. Each new string contains 36 optical modules, bringing the total number of modules to 302, at depths of 1.6 to 2 kilometers (about 1 to 1.25 miles). AMANDA-A, the upper part of the detector that was installed during the 1993-1994 austral summer, consists of four 1-kilometer-long strings, each with 20 optical modules. Even before the six new strings were added this season, AMANDA had demonstrated its effectiveness: it functioned as expected, and it detected neutrinos.
AMANDA is a collaboration of U.S., German,
and Swedish scientists. Visit the AMANDA home page on the Web at http://amanda.berkeley.edu
for more information.
The Automatic Geophysical Observatory (AGO) network added a sixth unit. AGOs operate unattended for about a year at a time on the east antarctic plateau. These small, low-powered units transmit some operational and meteorological data via satellite, but most of the data they gather are stored on optical disk and retrieved annually. Originally, the AGO network was built to study the polar ionosphere and magnetosphere, but in recent years the functions have been expanded to include other Earth-related studies. When data collected by the U.S. AGOs are combined with data from several of the manned antarctic stations and from other nations' AGOs, the wealth of information gathered on the high geomagnetic latitude ionosphere provides a much better understanding of the Earth's response to solar activity.
During the 1996-1997 austral summer, scientists made operational the sixth and last of the U.S. AGO units. The AGO program is a collaboration of scientists from several nations. These Web sites contain more information about the U.S. AGOs:
CARA, taking advantage of the unique astronomical location at the geographic South Pole and the unequaled clarity of the antarctic atmosphere, operated four major research projects at Amundsen-Scott South Pole Station. The Center for Astrophysical Research in Antarctica (CARA) is managed by the University of Chicago and involves researchers from eight U.S. institutions and one German institution. CARA researchers also conduct joint research with collaborators from the National Aeronautics and Space Administration (NASA), two U.S. universities, and Australian and French researchers. (See http://astro.uchicago.edu/cara/home.html.) The following are the four main research projects.
U.S. and French team successfully retrieved a $10-million Flare Genesis telescope. The second largest solar telescope, called Flare Genesis, circled Antarctica during the 1995-1996 summer suspended from a 29.4-million-cubic-foot, high-altitude helium balloon. Taking advantage of the 24-hour daylight, Flare Genesis acquired, during its 19-day flight, 14,000 solar images (including images of sunspots) and mapped associated magnetic fields, which are believed to cause solar flares.
Flare Genesis's 80-centimeter-diameter mirror can resolve features as small as 150 kilometers on the Sun. The principal objective of the Flare Genesis missions is to understand the origins of solar activity. Scientists hope to learn more about such key features as magnetic energy buildup and release on the Sun and, one day, to reliably forecast solar activity, which sends dangerous shocks and atomic particles to Earth.
In January 1996, the balloon came down south
of the Adélie Coast, 1,400 kilometers from McMurdo Station. Hazardous
weather permitted only the data recorder to be retrieved. During the 1996-1997
austral summer, the French Antarctic Program assisted U.S. researchers
in a traverse to the site to recover the balloon payload, including the
$10-million telescope. (See http://sd-www.jhuapl.edu/FlareGenesis/flare.html
for more information.)
Archaea have been found in extremely hot or saline environments such as hot springs, salt evaporation pans, and deep sea hydrothermal vents—places where no other life can survive. During the 1996-1997 research season, biologists working in the waters off Palmer Station discovered that a significant percentage of the planktonic microbes in cold (-1.5°C) southern ocean waters are archaea.
Archaea from hot and cold environments are closely related. They produce similar fatty acids and have similar genomic structures. The percentage of archaea found in the southern ocean sampling represents the highest rate measured to date in any of the world's oceans.
Icefish, whose bodies produce antifreeze glycopeptides to keep them from freezing, were found to possess an additional protective mechanism . Because of the high salt content, seawater surrounding Antarctica freezes at a temperature about 2°C below that of freshwater. Fish swimming in these waters theoretically should freeze, but their blood and tissues contain glycopeptides that prevent freezing. These compounds act by attaching to small ice crystals and preventing them from joining together to form larger crystals. Recently, investigators found another protective mechanism at work. Apparently, antibodies in the blood of these fishes seek out ice crystals and transport them to the spleen where they are expelled.
Because the fish antifreeze proteins are effective in inhibiting ice growth, researchers believe that the proteins could be used to prevent freezing and freezing injury in other applications. They have successfully cloned and characterized the genes of antifreeze proteins, producing two of the four different types of fish antifreeze proteins in yeast and bacteria through recombinant DNA technology. Using these cloned genes and molecular technology, researchers can produce large quantities of antifreeze proteins through large-scale fermentation.
Additionally, researchers believe that by
transferring the antifreeze protein genes into the systems of selected
plants and animals, they may be able to enhance cold or freeze tolerance.
They are assessing the potential application of these proteins in cryomedical
preservation, protection of frozen foods from recrystallization, enhancement
of freeze or cold resistance, and use as nonpolluting de-icing agents.
(See http://www.life.uiuc.edu/physiology/faculty/devries.html
to learn more about the work of Arthur DeVries, a leading researcher in
this field, and http://www.oc.uiuc.edu/NB/97.05/9705fishtip.html
for related information.
Scientists gathered samples of sea life from beneath the pack ice. Although the growth and retreat of the sea ice around Antarctica is one of the world's great seasonal events, little is known about how changes in the ice cover affect zooplankton and other animals in the ocean's upper 100 meters (the epipelagic zone), where light penetrates the water or ice enough to allow photosynthesis to occur.
During three cruises to the Weddell Sea in April and May 1996 and in November and December 1996, investigators collected samples by trawling and tracked the seasonal variations in the life cycle of these tiny animals by comparing the results from their trawls with the earlier findings of other investigators. Results indicated substantial differences in community composition from season to season. Trawls from April and May 1996 contained up to 100 times more biomass than samples from September and October 1995. Collections from November and December 1996 were intermediate in size between the other two sampling periods.
Analyzing the data from these three cruises and comparing the results from periods having different degrees of ice cover should give researchers greater insight into the role that the seasonal ice cover plays in structuring antarctic epipelagic communities.
Read more about this research on pages 88-90,
"Epipelagic
communities in the northwestern Weddell Sea: Results from high-resolution
trawl surveys" by R.S. Kaufmann and K.L. Smith, Jr.
Glaciologists and geologists believe the
information being collected by SOAR will be crucial to understanding the
behavior of the massive ice sheet and determining to what extent the ice
sheet is affected by the geologic rift on which it formed. (See http://www.ig.utexas.edu/research/projects/soar/soar.html.)
Global positioning system (GPS) based tectonics research provided a new means to study the Earth's crust . Several projects used GPS technology to measure tectonic plate and vertical crust movements beneath the ice of Antarctica. The weight of glacial ice has a tremendous effect on the Earth's surface beneath it. Researchers believe that the vertical velocities they measured this season will reflect the Earth's viscous, elastic response to changes in the size and extent of Antarctica's ice sheets and will help them understand how periods of glaciation and warming in the past deformed the Earth's surface.
During the 1996-1997 season, a real-time
differential GPS station was tested at McMurdo; a more permanent station
was installed during the 1997-1998 austral summer. The high-precision differential
positioning technology enables new antarctic geophysical investigations
that could yield globally significant results before the turn of the century.
The system provides accurate, real-time readings from handheld receivers
and far more precise readings using station equipment at McMurdo. Differential
GPS simplifies many survey tasks that would otherwise require time-consuming
collection and postprocessing of data. (See the University NAVSTAR Consortium
Web site at http://www.unavco.ucar.edu/polar
for more information.)
Antarctic Search for Meteorites (ANSMET) teams recovered 390 meteorites. The news in mid-1996 that ALH84001, a meteorite from Mars found in Antarctica's Allan Hills in 1984, may contain fossil evidence of early life called attention to the work of ANSMET, led by Ralph P. Harvey, Case Western Reserve University. Each year, Harvey's field teams retrieve hundreds of meteorites. Since the project began in 1976, ANSMET has brought more than 7,800 specimens, including samples from the Moon and Mars, to the United States for study.
During 1996-1997, ANSMET traveled to the Elephant Moraine-Reckling Moraine region, which had already yielded over 2,000 specimens. Of the 390 recovered this year, several were initially identified as being unusual, although detailed characterization remained to be completed.
Antarctica is unequaled as a location for finding meteorites. Although meteorites fall all over the globe, the likelihood of finding them is increased in Antarctica where the ice background provides stark contrast to the dark rocks. Close to half of the total meteorites found on Earth have been found in Antarctica.
See http://www.cwru.edu/affil/ansmet/index.html
and http://www-curator.jsc.nasa.gov/curator/antmet/marsmets/contents.htm.
In this issue, refer to "Meteorite
studies: Terrestrial and extra-terrestrial applications, 1997" by M.E.
Lipschutz (pages 23-25) and "Meteorite
recovery and reconnaissance in the Allan Hills-David Glacier and Darwin
Glacier regions, 1996-1997" by R.P. Harvey and J.W. Schutt (pages 25-27).
Geophysicists determined this field season
that the base of this ice sheet is 3,750±20 meters below its surface.
Below the ice-sheet base lies a subglacial lake, named Lake Vostok by researchers,
a huge freshwater body believed to be the size of Lake Ontario. The lake
and any life it may harbor have been sealed off from the atmosphere for
hundreds of thousands and perhaps many millions of years. To avoid contaminating
the lake, researchers currently plan to halt the drilling at about 3,700
meters. (For more information about the Vostok core, see http://www.agu.org/sci_soc/vostok.html
and about Lake Vostok, see http://www.nerc-bas.ac.uk/public/press/vostok.html.)
Researchers prepared for deep coring at Siple Dome to be done during the 1997-1998 season. As part of the West Antarctic Ice Sheet Initiative, researchers are undertaking a multiyear effort to retrieve a deep core from Siple Dome, an ice rise located between two ice streams that feed into the Ross Ice Shelf. Glaciologists believe that Siple Dome is a critical location for studying the dynamics of the west antarctic ice sheet.
During the 1996-1997 austral summer, a field camp was established, and shallow cores were retrieved from a number of sites surrounding the main drill site. These shallow cores were shipped to the National Ice Core Laboratory in Denver for processing and examination.
At the main site, workers drilled to 60 meters, and the drill hole was cased in preparation for the deep drilling to be done during the 1997-1998 field season, when investigators hope to reach bedrock, 1,000 meters below the ice surface. The core's record is expected to span 80,000 years and should reveal much about climate changes as well as the movement of the west antarctic ice sheet from the last glaciation to the present day. Glaciologists want to compare the data gathered from this core with similar data gathered from a deep core drilled in Greenland to see if climate changes recorded there represent local or global phenomena.
Two articles in this issue describe the season's work at Siple Dome:
The Weddell Polynya Quick Response program
sought to predict polynya recurrence. The Weddell polynya is a large
area of open water, about a third of a million square kilometers, within
the winter ice cover. It is caused by the upwelling of relatively warm
water that melts the ice. The Weddell polynya was observed by satellite
from 1974 to 1976. Although it has not recurred since, several precursors
to the development of the polynya have occurred recently. Scientists who
developed the Weddell Polynya Quick Response program during the 1996-1997
season hope that by studying and tracking the Weddell ocean dynamics that
lead to the formation of a polynya, they can place a ship into a forming
polynya and gather new information about this sea-ice phenomenon.
Antarctic automatic weather stations provided reliable, accurate data for another year. Approximately 50 automatic weather stations transmitted data throughout the 1996-1997 season. These rugged instruments, developed for the U.S. Antarctic Program, have performed well in some of the most rigorous climatic conditions on Earth. Measurements of surface temperature, pressure, wind, and humidity are transmitted to polar-orbiting satellites and delivered electronically for weather forecasting and research purposes to users in Antarctica and in the United States. The automatic weather stations are the primary direct data source for much of the antarctic continent and represent a valuable data set for validating satellite imagery.
Records of the antarctic automatic weather stations for the past two research seasons can be found in two articles in this issue, and a third article describes the work of the Antarctic Meteorological Research Center:
Preliminary results from the first season of operation indicated the following.
The data gathered by the two devices will
help investigators assess the atmospheric pollution impact that human activities
at the South Pole have on the antarctic environment. The article by A.D.A.
Hansen, "Measurement
of combustion effluent aerosols from Amundsen-Scott South Pole Station"
(pages 163-164 in this issue), discusses this project in greater detail
.
In October 1991, the United States and 25 other nations signed the Protocol on Environmental Protection, which builds on the Antarctic Treaty to provide a comprehensive system to protect the antarctic environment and its associated and dependent ecosystems. For the Protocol to become a legally binding agreement, the 26 consultative nations that signed the agreement in 1991 needed to ratify it in accordance with their own constitutional processes. The United States completed its ratification with passage of the Antarctic Science, Tourism and Conservation Act of 1996, which President Clinton signed into law on 2 October 1996.
By affirming the principles of the Antarctic
Treaty, the protocol helps to ensure that Antarctica will continue to be
a natural reserve, devoted to peace and science. Among the provisions of
the protocol is a ban on all activities related to mineral resources except
for scientific research. The protocol also commits parties to environmental
impact assessment procedures for planned activities, both governmental
and private. It enhances the protective measures accorded to fauna and
flora and imposes strict limitations on the disposal of wastes and discharge
of pollutants, both land based and shipboard. Changes to the terms used
for designating protected areas are included in one of the annexes to the
protocol, though adoption of those changes must be made separately by the
Treaty parties.
The United States, through regulations
that were issued under the Antarctic Conservation Act, has been complying
with most of the protocol even before the U.S. Congress ratified the international
agreement. The passage of H.R. 3060 and its signing by the President bring
the force of law to antarctic environmental protection and designate specific
responsibilities for federal agencies to enforce the protocol. (Read the
complete text of the protocol at this Web site: http://www.icair.iac.org.nz/treaty/protocol/protcon.html.)
The External Panel studying U.S. presence in Antarctica made 12 recommendations to NSF . On 12 March 1997, Norman R. Augustine, Chairman of the U.S. Antarctic Program External Panel, presented to the House Committee on Science the committee's recommendations that resulted from the panel's 9-month examination of infrastructure, management, and scientific options. Their findings and recommendations were developed to help maintain a high-quality research program and U.S. policy to provide an active and influential presence in Antarctica, while operating within a realistic budget. The panel's review emphasized the high geopolitical, scientific, and environmental value of the antarctic program.
In response to a Congressional mandate, Dr. Neal Lane, Director of the NSF, had established the U.S. Antarctic Program External Panel in August 1996. The charge given to the 11-member panel by Dr. Lane was to "examine and make recommendations concerning the stations and logistics systems that support the science while maintaining appropriate environmental, safety, and health standards; the efficiency and appropriateness of the management of these support systems; and how and at what level the science programs are implemented." The panel members were also asked to consider the eventual replacement of Amundsen-Scott South Pole Station and other infrastructures.
In his testimony to the House Committee on Science, Mr. Augustine summarized the External Panel's findings and recommendations and answered questions. The panel's complete report, The United States in Antarctica—Report of the U.S. Antarctic Program External Panel (April 1997), is online at https://www.nsf.gov/cgi-bin/getpub?antpanel. (Printed copies are available from the Antarctic Sciences Section of NSF, room 755, phone 703/306-1031.) Highlights of Mr. Augustine's testimony follow.
With nearly 50 years of experience, PHI,
a Louisiana-based company, is one of the world's largest and most experienced
commercial helicopter operators. The firm's clients include national and
international offshore oil, land-based mining, and aeromedical companies.
In addition to providing services to North American companies, PHI has
operated in 38 foreign countries worldwide. During the 1996-1997 season,
seven pilots and five mechanics flew and maintained the four helicopters,
which are based at McMurdo Station. (For more information, see the PHI
Web site at http://www.phihelico.com/.)
The research ship Polar Duke retired from antarctic duty at the end of the 1996-1997 season. In June 1997, the Polar Duke headed north, leaving Antarctica after serving antarctic science for 13 years. Designed and built for research and supply work in the north polar seas, Polar Duke was christened in Kyrksæterøra, Norway, in 1983 by Rieber Shipping A/S of Bergen, Norway. When North Sea oil exploration waned, Rieber chartered the ice-strengthened ship to the U.S. Antarctic Program for research and support work. In January 1985, the Duke replaced the NSF-owned wooden research ship Hero, which was retired from south polar duty after 17 years of service.
Initially, Polar Duke was chartered to do what the Hero had done: perform austral summer research and resupply. In its first season, which lasted from January to April 1985, the Duke made three cruises between Punta Arenas, Chile, and the Antarctic Peninsula. The next year, however, Langdon Quetin of the University of California-Santa Barbara proposed a rare winter cruise. The success of this cruise, and one that followed during the austral winter of 1987, established Polar Duke as a year-round vessel. From the 1988-1989 austral summer season until its 1997 contract completion, the ship logged 275 to 300 days at sea per year in support of U.S. Antarctic Program science.
Polar Duke made possible countless landmark projects in the disciplines of physiology, microbiology, and oceanography and, in support of science and scientists, navigated some of the roughest waters in the world, including the Drake Passage between South America and the Antarctic Peninsula. In addition to serving as a research laboratory, Polar Duke also transported people, equipment, food, construction supplies, and other materials from Tierra del Fuego to Palmer Station and to seasonal field camps and other outposts. During the 1989-1990 operating year, Polar Duke made its first ever call at McMurdo Station. From the time of its charter in 1985 until it headed north in retirement in 1997, the Duke left the Southern Hemisphere only once: in 1995, the vessel carried a shipment of hazardous waste to the U.S. mainland for final processing and disposal.
A new ice-strengthened research vessel, Laurence M. Gould, was to replace Polar Duke in Antarctica next season. (For more information, visit Antarctic Support Associate's page for the Gould at http://www.asa.org/marine/lmg/lmgtofc.htm.)
For Fiscal Year 1997, the National Science Foundation received $193.52 million for the U.S. Antarctic Program. With these funds, NSF funded scientists working in Antarctica and at facilities in the United States and operations in Antarctica in support of the U.S. research effort. The funds fall into three major categories:
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Funds ($30.63 million) provided for the U.S. Antarctic Research Program were awarded for research and related grants in the following categories:
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