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USGS2007

Advances through collaboration: sharing seismic reflection data via the Antarctic Seismic Data Library System for Cooperative Research (SDLS)

The Antarctic Seismic Data Library System for Cooperative Research (SDLS) has served for the past 16 years under the auspices of the Antarctic Treaty (ATCM Recommendation XVI-12) as a role model for collaboration and equitable sharing of Antarctic multichannel seismic reflection (MCS) data for geoscience studies. During this period, collaboration in MCS studies has advanced deciphering the seismic stratigraphy and structure of Antarctica’s continental margin more rapidly than previously. MCS data compilations provided the geologic framework for scientific drilling at several Antarctic locations and for high-resolution seismic and sampling studies to decipher Cenozoic depositional paleoenvironments. The SDLS successes come from cooperation of National Antarctic Programs and individual investigators in “on-time” submissions of their MCS data. Most do, but some do not. The SDLS community has an International Polar Year (IPY) goal of all overdue MCS data being sent to the SDLS by end of IPY. The community science objective is to compile all Antarctic MCS data to derive a unified seismic stratigraphy for the continental margin – a stratigraphy to be used with drilling data to derive Cenozoic circum-Antarctic paleobathymetry maps and local-to-regional scale paleoenvironmental histories.

Open-File Report↗

USGS2007

U.S. Geological Survey Scientific Activities in the Exploration of Antarctica: Introduction to Antarctica (Including USGS Field Personnel: 1946-59)

INTRODUCTION Antarctica is the planet's fifth largest continent [13.2 million km2 (5.1 million mi2)]; it contains the Earth's largest (of two) remaining ice sheets; it is considered to be one of the most important scientific laboratories on Earth. This report is the introduction to a series that covers 60 years of U.S. Geological Survey (USGS) scientific activity in Antarctica. It will concentrate primarily on three major topics: 1) a brief chronological record of the historical search, discovery, and exploration of the southern continent by humans; 2) early USGS scientific activities in Antarctica, listing expeditions, projects, people and resulting professional publications for Operation Highjump, 1946-47; Operation Windmill, 1947-48; USS Atka Reconnaissance Cruise, 1954-55; and Operation Deep Freeze I, II, III, and IV, 1955-59, including IGY; 3) significant changes that have occurred in Antarctic exploration and research since World War II will be discussed at the end of this report. Subsequent Open-File Reports will provide a year-by-year documentation of USGS scientific activities and accomplishments in Antarctica beginning with the post-IGY, 1959-60 research team. One Open-File Report is planned to be written for each field-based season. For an example of the series format, see Open-File Reports 2006-1113 (Meunier, 2007a) and 2006-1114 (Meunier, 2007b). This report is a companion document to Open-File Report 2006-1116 (Meunier, 2007c). The USGS mapping and science programs in Antarctica are among the longest continuously funded projects in the United States Antarctic Program (USAP). The 2005-06 field season is the 56th consecutive U.S. expedition in which USGS scientists have been participants, starting in 1946. USGS and the National Science Foundation (NSF) cooperation began with the establishment by NSF of the U.S. Antarctic (Research) Program [USA(R)P] in 1958-59 under Operation Deep Freeze IV (DF IV) and was given the responsibility for the principal coordination and management of all U.S. scientific activities in Antarctica in Deep Freeze 60 (DF 60) (1959-60). Financial support from NSF, mostly in the form of Memorandum of Understandings (MOUs) and Cooperative Agreements, extends back to this period and can be attributed to the need for accurate geologic, geophysical, and topographic base maps of specific field areas or regions where NSF-funded science projects were planned. The epoch of Antarctic exploration during the IGY was driven by science and, in a spirit of peaceful cooperation, the international scientific community wanted to limit military activities on the continent to logistical support (Meunier, 1979 [2007], p. 38). The USGS, a Federal civilian science agency in the Department of the Interior, has, since its founding in 1879, carried out numerous field-based national (and some international) programs in biology, geology, geophysics, hydrology, and mapping. Therefore, the USGS was the obvious choice for these tasks, because it already had a professional staff of experienced mapmakers, scientists, and program managers with the foresight, dedication, and understanding of the need for accurate maps to support the science programs in Antarctica when asked to do so by the U.S. National Academy of Sciences. Public Laws 85-743 and 87-626, signed in August 1958, and in September 1962, respectively, authorized the Secretary, U.S. Department of the Interior, through the USGS, to support mapping and scientific work in Antarctica (Meunier, 1979 [2007], appendix A). Open-File Report 2006-1116 includes scanned facsimiles of postal cachets. It has become an international practice to create postal cachets to commemorate special events and projects in Antarctica. A cachet is defined as a seal or commemorative design printed or stamped on an envelope to mark a philatelic or special event. The inked impression illustrates to the scientist, historian, stamp collector, and general public the multidisciplinary science projects staffed by USGS and collaborating scientists during the field season. Since 1960, philatelic cachets have been created by team members for each USGS field season and, in most cases, these cachets depict the specific geographic areas and field season program objectives. The cachets become a convenient documentation of the people, projects, and geographic places of interest for that year. Because the cachets are representative of USGS activities, each year's cachet is included as a digital facsimile in that year's Open-File Report. In the 1980s, multiple USGS cachets were prepared each year, one for use by the winter team at Amundsen-Scott South Pole Station and the other for the project work areas of the austral summer field season programs.

Open-File Report↗

USGS2003

Coastal-change and glaciological map of the Bakutis Coast, Antarctica: 1972-2002

Changes in the area and volume of the polar ice sheets are intricately linked to changes in global climate, and the resulting changes in sea level may severely impact the densely populated coastal regions on Earth. Loss of the West Antarctic part of the Antarctic ice sheet alone could cause a sea-level rise of approximately 6 m. The potential sea-level rise after melting of the entire Antarctic ice sheet is estimated to be 65 m to 73 m. In spite of its importance, the mass balance (the net volumetric gain or loss) of the Antarctic ice sheet is poorly known; it is not known whether the ice sheet is growing or shrinking. As a result, measurement of changes in the Antarctic ice sheet was given a very high priority in recommendations by the Polar Research Board of the National Research Council (1986), by the Scientific Committee on Antarctic Research (SCAR) (1989), and by the National Science Foundation's (1990) Division of Polar Programs. An archive of early 1970's Landsat 1, 2, and 3 Multispectral Scanner (MSS) images of Antarctica and the fact that the repeat coverage with satellite images provided an excellent means of documenting changes in the coastline of Antarctica provided the impetus for carrying out a comprehensive analysis of the glaciological features of the coastal regions and changes in ice fronts of Antarctica. The project was later modified to include Landsat 4 and 5 MSS and Thematic Mapper (TM) and RADARSAT images to compare changes over a 20- to 25- year time interval and to prepare a series of 24 1:1,000,000-scale and 1 1:5,000,000-scale U.S. Geological Survey Geologic Investigations Series Maps ('I-Maps') (Williams and others, 1995; Williams and Ferrigno, 1998; and Ferrigno and others, 2002) in both paper and digital format.

IMAP↗

USGS2004

Coastal-change and glaciological maps of Antarctica

Changes in the area and volume of polar ice sheets are intricately linked to changes in global climate, and the resulting changes in sea level may severely impact the densely populated coastal regions on Earth. Melting of the West Antarctic part alone of the Antarctic ice sheet could cause a sea-level rise of approximately 6 meters (m). The potential sea-level rise after melting of the entire Antarctic ice sheet is estimated to be 65 m (Lythe and others, 2001) to 73 m (Williams and Hall, 1993). In spite of its importance, the mass balance (the net volumetric gain or loss) of the Antarctic ice sheet is poorly known; it is not known for certain whether the ice sheet is growing or shrinking. In a review paper, Rignot and Thomas (2002) concluded that the West Antarctic part of the Antarctic ice sheet is probably becoming thinner overall; although the western part is thickening, the northern part is thinning. Joughin and Tulaczyk (2002), based on analysis of ice-flow velocities derived from synthetic aperture radar, concluded that most of the Ross ice streams (ice streams on the east side of the Ross Ice Shelf) have a positive mass balance. The mass balance of the East Antarctic is unknown, but thought to be in near equilibrium. Measurement of changes in area and mass balance of the Antarctic ice sheet was given a very high priority in recommendations by the Polar Research Board of the National Research Council (1986), in subsequent recommendations by the Scientific Committee on Antarctic Research (SCAR) (1989, 1993), and by the National Science Foundation's (1990) Division of Polar Programs. On the basis of these recommendations, the U.S. Geological Survey (USGS) decided that the archive of early 1970s Landsat 1, 2, and 3 Multispectral Scanner (MSS) images of Antarctica and the subsequent repeat coverage made possible with Landsat and other satellite images provided an excellent means of documenting changes in the coastline of Antarctica (Ferrigno and Gould, 1987). The availability of this information provided the impetus for carrying out a comprehensive analysis of the glaciological features of the coastal regions and changes in ice fronts of Antarctica (Swithinbank, 1988; Williams and Ferrigno, 1988). The project was later modified to include Landsat 4 and 5 MSS and Thematic Mapper (TM) (and in some areas Landsat 7 Enhanced Thematic Mapper Plus (ETM+)), RADARSAT images, and other data where available, to compare changes over a 20- to 25- or 30-year time interval (or longer where data were available, as in the Antarctic Peninsula). The results of the analysis are being used to produce a digital database and a series of USGS Geologic Investigations Series Maps consisting of 24 maps at 1:1,000,000 scale and 1 map at 1:5,000,000 scale, in both paper and digital format (Williams and others, 1995; Williams and Ferrigno, 1998; and Ferrigno and others, 2002).

IMAP↗

USGS2004

Coastal-change and glaciological map of the Eights Coast area, Antarctica, 1972-2001

IMAP↗

USGS2003

Coastal-change and glaciological map of the Saunders Coast area, Antarctica: 1972-1997

Changes in the area and volume of polar ice sheets are intricately linked to changes in global climate, and the resulting changes in sea level may severely impact the densely populated coastal regions on Earth. Melting of the West Antarctic part alone of the Antarctic ice sheet could cause a sea-level rise of approximately 6 meters (m). The potential sea-level rise after melting of the entire Antarctic ice sheet is estimated to be 65 m (Lythe and others, 2001) to 73 m (Williams and Hall, 1993). In spite of its importance, the mass balance (the net volumetric gain or loss) of the Antarctic ice sheet is poorly known; it is not known for certain whether the ice sheet is growing or shrinking. In a review paper, Rignot and Thomas (2002) concluded that the West Antarctic part of the Antarctic ice sheet is probably becoming thinner overall; although the western part is thickening, the northern part is thinning. Joughin and Tulaczyk (2002), based on analysis of ice-flow velocities derived from synthetic aperture radar, concluded that most of the Ross ice streams (ice streams on the east side of the Ross Ice Shelf) have a positive mass balance. The mass balance of the East Antarctic is unknown, but thought to be in near equilibrium. Measurement of changes in area and mass balance of the Antarctic ice sheet was given a very high priority in recommendations by the Polar Research Board of the National Research Council (1986), in subsequent recommendations by the Scientific Committee on Antarctic Research (SCAR) (1989, 1993), and by the National Science Foundation?s (1990) Division of Polar Programs. On the basis of these recommendations, the U.S. Geological Survey (USGS) decided that the archive of early 1970s Landsat 1, 2, and 3 Multispectral Scanner (MSS) images of Antarctica and the subsequent repeat coverage made possible with Landsat and other satellite images provided an excellent means of documenting changes in the coastline of Antarctica (Ferrigno and Gould, 1987). The availability of this information provided the impetus for carrying out a comprehensive analysis of the glaciological features of the coastal regions and changes in ice fronts of Antarctica (Swithinbank, 1988; Williams and Ferrigno, 1988). The project was later modified to include Landsat 4 and 5 MSS and Thematic Mapper (TM) (and in some areas Landsat 7 Enhanced Thematic Mapper Plus (ETM+)), RADARSAT images, and other data where available, to compare changes over a 20- to 25- or 30-year time interval (or longer where data were available, as in the Antarctic Peninsula). The results of the analysis are being used to produce a digital database and a series of USGS Geologic Investigations Series Maps consisting of 24 maps at 1:1,000,000 scale and 1 map at 1:5,000,000 scale, in both paper and digital format (Williams and others, 1995; Williams and Ferrigno, 1998; and Ferrigno and others, 2002).

IMAP↗

USGS2006

Coastal-change and glaciological map of the Trinity Peninsula area and south Shetland Islands, Antarctica: 1843-2001: Chapter A in Coastal-change and glaciological maps of Antarctica

Changes in the area and volume of polar ice sheets are intricately linked to changes in global climate, and the resulting changes in sea level could severely impact the densely populated coastal regions on Earth. Melting of the West Antarctic part alone of the Antarctic ice sheet would cause a sea-level rise of approximately 6 meters (m). The potential sea-level rise after melting of the entire Antarctic ice sheet is estimated to be 65 m (Lythe and others, 2001) to 73 m (Williams and Hall, 1993). In addition to its importance, the mass balance (the net volumetric gain or loss) of the Antarctic ice sheet is highly complex, responding differently to different conditions in each region (Vaughan, 2005). In a review paper, Rignot and Thomas (2002) concluded that the West Antarctic ice sheet is probably becoming thinner overall; although it is thickening in the west, it is thinning in the north. Thomas and others (2004), on the basis of aircraft and satellite laser altimetry surveys, believe the thinning may be accelerating. Joughin and Tulaczyk (2002), on the basis of analysis of ice-flow velocities derived from synthetic aperture radar, concluded that most of the Ross ice streams (ice streams on the east side of the Ross Ice Shelf) have a positive mass balance, whereas Rignot and others (2004) infer even larger negative mass balance for glaciers flowing northward into the Amundsen Sea, a trend suggested by Swithinbank and others (2003a,b, 2004). The mass balance of the East Antarctic ice sheet is thought by Davis and others (2005) to be strongly positive on the basis of the change in satellite altimetry measurements made between 1992 and 2003. Measurement of changes in area and mass balance of the Antarctic ice sheet was given a very high priority in recommendations by the Polar Research Board of the National Research Council (1986), in subsequent recommendations by the Scientific Committee on Antarctic Research (SCAR) (1989, 1993), and by the National Science Foundation's (1990) Division of Polar Programs. On the basis of these recommendations, the U.S. Geological Survey (USGS) decided that the archive of early 1970s Landsat 1, 2, and 3 Multispectral Scanner (MSS) images of Antarctica and the subsequent repeat coverage made possible with Landsat and other satellite images provided an excellent means of documenting changes in the coastline of Antarctica (Ferrigno and Gould, 1987). The availability of this information provided the impetus for carrying out a comprehensive analysis of the glaciological features of the coastal regions and changes in ice fronts of Antarctica (Swithinbank, 1988; Williams and Ferrigno, 1988). The project was later modified to include Landsat 4 and 5 MSS and Thematic Mapper (TM) [and in some areas Landsat 7 Enhanced Thematic Mapper Plus (ETM+)], RADARSAT images, and other data where available, to compare changes that occurred during a 20- to 25- or 30-year time interval (or longer where data were available, as in the Antarctic Peninsula). The results of the analysis are being used to produce a digital database and a series of USGS Geologic Investigations Series Maps (I–2600) consisting of 23 maps at 1:1,000,000 scale and 1 map at 1:5,000,000 scale, in both paper and digital format (Williams and others, 1995; Williams and Ferrigno, 1998; Ferrigno and others, 2002).

IMAP↗

USGS2005

Coastal-change and glaciological map of the Ronne Ice Shelf area, Antarctica, 1974-2002

Changes in the area and volume of polar ice sheets are intricately linked to changes in global climate, and the resulting changes in sea level may severely impact the densely populated coastal regions on Earth. Melting of the West Antarctic part alone of the Antarctic ice sheet could cause a sea-level rise of approximately 6 meters (m). The potential sea-level rise after melting of the entire Antarctic ice sheet is estimated to be 65 m (Lythe and others, 2001) to 73 m (Williams and Hall, 1993). In spite of its importance, the mass balance (the net volumetric gain or loss) of the Antarctic ice sheet is poorly known; it is not known for certain whether the ice sheet is growing or shrinking. In a review paper, Rignot and Thomas (2002) concluded that the West Antarctic part of the Antarctic ice sheet is probably becoming thinner overall; although it is thickening in the west, it is thinning in the north. Joughin and Tulaczyk (2002), on the basis of analysis of ice-flow velocities derived from synthetic aperture radar, concluded that most of the Ross ice streams (ice streams on the east side of the Ross Ice Shelf) have a positive mass balance, whereas Rignot and others (in press) infer even larger negative mass balance for glaciers flowing northward into the Amundsen Sea, a trend suggested by Swithinbank and others (2003a,b, 2004). The mass balance of the East Antarctic part of the Antarctic ice sheet is unknown, but thought to be in near equilibrium. Measurement of changes in area and mass balance of the Antarctic ice sheet was given a very high priority in recommendations by the Polar Research Board of the National Research Council (1986), in subsequent recommendations by the Scientific Committee on Antarctic Research (SCAR) (1989, 1993), and by the National Science Foundation's (1990) Division of Polar Pro-grams. On the basis of these recommendations, the U.S. Geo-logical Survey (USGS) decided that the archive of early 1970s Landsat 1, 2, and 3 Multispectral Scanner (MSS) images of Ant-arctica and the subsequent repeat coverage made possible with Landsat and other satellite images provided an excellent means of documenting changes in the coastline of Antarctica (Ferrigno and Gould, 1987). The availability of this information provided the impetus for carrying out a comprehensive analysis of the glaciological features of the coastal regions and changes in ice fronts of Antarctica (Swithinbank, 1988; Williams and Ferrigno, 1988). The project was later modified to include Landsat 4 and 5 MSS and Thematic Mapper (TM) (and in some areas Landsat 7 Enhanced Thematic Mapper Plus (ETM+)), RADARSAT images, and other data where available, to compare changes during a 20- to 25- or 30-year time interval (or longer where data were available, as in the Antarctic Peninsula). The results of the analysis are being used to produce a digital database and a series of USGS Geologic Investigations Series Maps (I-2600) consisting of 23 maps at 1:1,000,000 scale and 1 map at 1:5,000,000 scale, in both paper and digital format (Williams and others, 1995; Williams and Ferrigno, 1998; Ferrigno and others, 2002) (available online at http://www.glaciers.er.usgs.gov).

IMAP↗

USGS2007

Coastal-Change and Glaciological Map of the Northern Ross Ice Shelf Area, Antarctica: 1962-2004

Changes in the area and volume of polar ice sheets are intricately linked to changes in global climate, and the resulting changes in sea level could severely impact the densely populated coastal regions on Earth. Melting of the West Antarctic part alone of the Antarctic ice sheet would cause a sea-level rise of approximately 6 meters (m). The potential sea-level rise after melting of the entire Antarctic ice sheet is estimated to be 65 m (Lythe and others, 2001) to 73 m (Williams and Hall, 1993). The mass balance (the net volumetric gain or loss) of the Antarctic ice sheet is highly complex, responding differently to different conditions in each region (Vaughan, 2005). In a review paper, Rignot and Thomas (2002) concluded that the West Antarctic ice sheet is probably becoming thinner overall; although it is thickening in the west, it is thinning in the north. Thomas and others (2004), on the basis of aircraft and satellite laser altimetry surveys, believe the thinning may be accelerating. Joughin and Tulaczyk (2002), on the basis of analysis of ice-flow velocities derived from synthetic aperture radar, concluded that most of the Ross ice streams (ice streams on the east side of the Ross Ice Shelf) have a positive mass balance, whereas Rignot and others (2004) infer even larger negative mass balance for glaciers flowing northward into the Amundsen Sea, a trend suggested by Swithinbank and others (2003a,b; 2004). The mass balance of the East Antarctic ice sheet is thought by Davis and others (2005) to be strongly positive on the basis of the change in satellite altimetry measurements made between 1992 and 2003. Measurement of changes in area and mass balance of the Antarctic ice sheet was given a very high priority in recommendations by the Polar Research Board of the National Research Council (1986), in subsequent recommendations by the Scientific Committee on Antarctic Research (SCAR) (1989, 1993), and by the National Science Foundation?s (1990) Division of Polar Programs. On the basis of these recommendations, the U.S. Geological Survey (USGS) decided that the archive of early 1970s Landsat 1, 2, and 3 Multispectral Scanner (MSS) images of Antarctica and the subsequent repeat coverage made possible with Landsat and other satellite images provided an excellent means of documenting changes in the coastline of Antarctica (Ferrigno and Gould, 1987). The availability of this information provided the impetus for carrying out a comprehensive analysis of the glaciological features of the coastal regions and changes in ice fronts of Antarctica (Swithinbank, 1988; Williams and Ferrigno, 1988). The project was later modified to include Landsat 4 and 5 MSS and Thematic Mapper (TM) images (and in some areas Landsat 7 Enhanced Thematic Mapper Plus [ETM+] images), RADARSAT images, and other data where available, in order to compare changes that occurred during a 20- to 25- or 30-year time interval (or longer where data were available, as in the Antarctic Peninsula). The results of the analysis are being used to produce a digital database and a series of USGS Geologic Investigations Series Maps (I?2600) (Williams and others, 1995; Williams and Ferrigno, 1998; Ferrigno and others, 2002) (available online at http://www.glaciers.er.usgs.gov).

IMAP↗

USGS2008

Coastal-Change and Glaciological Map of the Larsen Ice Shelf Area, Antarctica, 1940-2005

Changes in the area and volume of polar ice sheets are intricately linked to changes in global climate, and the resulting changes in sea level could severely impact the densely populated coastal regions on Earth. Antarctica is Earth's largest reservoir of glacial ice. Melting of the West Antarctic part alone of the Antarctic ice sheet would cause a sea-level rise of approximately 6 meters (m), and the potential sea-level rise after melting of the entire Antarctic ice sheet is estimated to be 65 m (Lythe and others, 2001) to 73 m (Williams and Hall, 1993). The mass balance (the net volumetric gain or loss) of the Antarctic ice sheet is highly complex, responding differently to different climatic and other conditions in each region (Vaughan, 2005). In a review paper, Rignot and Thomas (2002) concluded that the West Antarctic ice sheet is probably becoming thinner overall; although it is known to be thickening in the west, it is thinning in the north. The mass balance of the East Antarctic ice sheet is thought by Davis and others (2005) to be positive on the basis of the change in satellite-altimetry measurements made between 1992 and 2003. Measurement of changes in area and mass balance of the Antarctic ice sheet was given a very high priority in recommendations by the Polar Research Board of the National Research Council (1986), in subsequent recommendations by the Scientific Committee on Antarctic Research (SCAR) (1989, 1993), and by the National Science Foundation's (1990) Division of Polar Programs. On the basis of these recommendations, the U.S. Geological Survey (USGS) decided that the archive of early 1970s Landsat 1, 2, and 3 Multispectral Scanner (MSS) images of Antarctica and the subsequent repeat coverage made possible with Landsat and other satellite images provided an excellent means of documenting changes in the cryospheric coastline of Antarctica (Ferrigno and Gould, 1987). The availability of this information provided the impetus for carrying out a comprehensive analysis of the glaciological features of the coastal regions and changes in ice fronts of Antarctica (Swithinbank, 1988; Williams and Ferrigno, 1988). The project was later modified to include Landsat 4 and 5 MSS and Thematic Mapper (TM) images [and in some areas Landsat 7 Enhanced Thematic Mapper Plus (ETM+) images], RADARSAT images, aerial photography, and other data where available, to compare changes that occurred during a 20- to 25- or 30-year time interval (or longer where data were available, as in the Antarctic Peninsula). The results of the analysis are being used to produce a digital database and a series of USGS Geologic Investigations Series Maps (I-2600) (Williams and others, 1995; Ferrigno and others, 2002; and Williams and Ferrigno, 2005) (available online at http://www.glaciers.er.usgs.gov).

IMAP↗

USGS2009

Coastal-Change and Glaciological Map of the Palmer Land Area, Antarctica: 1947-2009

Reduction in the area and volume of the two polar ice sheets is intricately linked to changes in global climate, and the resulting rise in sea level could severely impact the densely populated coastal regions on Earth. Antarctica is Earth's largest reservoir of glacial ice. Melting of the West Antarctic part alone of the Antarctic ice sheet would cause a sea-level rise of approximately 6 meters (m), and the potential sea-level rise after melting of the entire Antarctic ice sheet is estimated to be 65 m (Lythe and others, 2001) to 73 m (Williams and Hall, 1993). The mass balance (the net volumetric gain or loss) of the Antarctic ice sheet is highly complex, responding differently to different climatic and other conditions in each region (Vaughan, 2005). In a review paper, Rignot and Thomas (2002) concluded that the West Antarctic ice sheet is probably becoming thinner overall; although it is known to be thickening in the west, it is thinning in the north. The mass balance of the East Antarctic ice sheet is thought by Davis and others (2005) to be positive on the basis of the change in satellite-altimetry measurements made between 1992 and 2003. Measurement of changes in area and mass balance of the Antarctic ice sheet was given a very high priority in recommendations by the Polar Research Board of the National Research Council (1986), in subsequent recommendations by the Scientific Committee on Antarctic Research (SCAR) (1989, 1993), and by the National Science Foundation's (1990) Division of Polar Programs. On the basis of these recommendations, the U.S. Geological Survey (USGS) decided that the archive of early 1970s Landsat 1, 2, and 3 Multispectral Scanner (MSS) images of Antarctica and the subsequent repeat coverage made possible with Landsat and other satellite images provided an excellent means of documenting changes in the cryospheric coastline of Antarctica (Ferrigno and Gould, 1987). The availability of this information provided the impetus for carrying out a comprehensive analysis of the glaciological features of the coastal regions and changes in ice fronts of Antarctica (Swithinbank, 1988; Williams and Ferrigno, 1988). The project was later modified to include Landsat 4 and 5 MSS and Thematic Mapper (TM) images (and in some areas Landsat 7 Enhanced Thematic Mapper Plus (ETM+) images), RADARSAT images, aerial photography, and other data where available, to compare changes that occurred during a 20- to 25- or 30-year time interval (or longer where data were available, as in the Antarctic Peninsula). The results of the analysis are being used to produce a digital database and a series of USGS Geologic Investigations Series Maps (I-2600) (Williams and others, 1995; Swithinbank and others, 2003a,b, 2004; Ferrigno and others, 2002, 2005, 2006, 2007, 2008, and in press; and Williams and Ferrigno, 2005) (available online at http://www.glaciers.er.usgs.gov).

IMAP↗

USGS2007

Landsat Image Mosaic of Antarctica (LIMA)

For most of us, Antarctica was at best a distant acquaintance. Now, with the Landsat Image Mosaic of Antarctica (LIMA), we are on intimate terms. In stunning, up-close and personal detail, LIMA brings Antarctica to life. Explore this virtually cloudless, seamless, most geometrically accurate, and highest resolution satellite mosaic of Antarctica. A team of scientists from the U.S. Geological Survey, the British Antarctic Survey, and the National Aeronautics and Space Administration, with funding from the National Science Foundation, created LIMA in support of the International Polar Year (IPY; 2007?08). As the first major scientific outcome of the IPY, LIMA truly fulfills the IPY goals. LIMA is an international effort, supports current scientific polar research, encourages new projects, and helps the general public visualize Antarctica and changes happening in this southernmost environment. Researchers and the general public can download LIMA and all component Landsat scenes at no charge.

Fact Sheet↗

USGS1977

Maps published of Antarctica by the U.S. Geological Survey

The Geological Survey in cooperation with the National Science Foundation prepares and publishes topographic maps of selected areas of Antarctica needed to support the U.S. Antarctic Research Program (USARP) efforts. These maps are prepared from aerial photography flown by U.S. Navy Air Development Squadron Six (VXE-6) in accordance with USGS specifications.

Report↗

USGS2021

Six decades of seismology at South Pole, Antarctica: Current limitations and future opportunities to facilitate new geophysical observations

Seismograms from the South Pole have been important for seismological observations for over six decades by providing (until 2007) the only continuous seismic records from the interior of the Antarctic continent. The South Pole, Antarctica station has undergone many updates over the years, including conversion to a digital recording station as part of the Global Seismographic Network (GSN) in 1991 and being relocated to multiple deep ( ⁠ > 250    m "> > 250 m >250 m ⁠ ) boreholes 8 km away from the station in 2003 (and renamed to Quiet South Pole, Antarctica [QSPA]). Notably, QSPA is the second most used GSN station by the National Earthquake Information Center to pick phases used to rapidly detect and locate earthquakes globally, and has been used for a variety of glaciological and oceanography studies. In addition, it is the only seismic station on the Earth where low‐frequency ( ⁠ < 5    mHz "> < 5 mHz <5 mHz ⁠ ), normal‐mode oscillations of the planet excited by large earthquakes can be recorded without influence from Earth’s rotation, and most of the direct effects of the solid Earth tide vanish. However, the current sensors are largely 1980s vintage, and, while able to make some lower‐frequency observations from earthquakes, the borehole sensors appear unable to resolve ambient ground motions at frequencies lower than 25 mHz due to instrument noise and contamination from magnetic field variations. Recently developed borehole sensors offer the potential to extend background noise observations to below 3 mHz, which would substantially improve the fidelity and scientific value of seismic observations at South Pole. Through collaboration with the IceCube Neutrino Observatory, the opportunity exists to emplace a modern very broadband seismometer near the base ( ⁠ > 2    km "> > 2 km >2 km depth) of the Antarctic ice cap, which could lead to unprecedented seismic observations at long periods and facilitate a broad spectrum of Earth science studies.

Seismological Research Letters↗

USGS2019

New and interesting species of the genus Muelleria (Bacillariophyta) from the Antarctic region and South Africa

During a survey of the terrestrial diatom flora of some sub-Antarctic islands in the southern Indian and Atlantic Oceans and of the Antarctic continent, more than 15 taxa belonging to the genus Muelleria were observed. Nine of these taxa are described as new species using light and scanning electron microscopy. Comments are made on their systematic position and how they are distinguished from other species in the genus. Additionally, two previously unrecognized taxa within the genus were discovered in samples from South Africa. One of these, Muelleria taylorii Van de Vijver & Cocquyt sp. nov., is new to science; the other, Muelleria vandermerwei (Cholnoky) Van de Vijver & Cocquyt nov. comb., had been included in the genus Diploneis. The large number of new Muelleria taxa on the (sub)-Antarctic locations is not surprising. Species in Muelleria occur rarely in collections; in many habitats, it is unusual to find more than 1-2 valves in any slide preparation. As a result, records are scarce. The practice of "force-fitting" (shoehorning) specimens into descriptions from common taxonomic keys (and species drift) results in European species, such as M. gibbula and M. linearis, being applied to Antarctic forms in ecological studies. Finally, the typical terrestrial habitats of soils, mosses and ephemeral water bodies of most of these taxa have been poorly studied in the past.

Phycologia↗

USGS2024

The EnMAP spaceborne imaging spectroscopy mission: Initial scientific results two years after launch

Imaging spectroscopy has been a recognized and established remote sensing technology since the 1980s, mainly using airborne and field-based platforms to identify and quantify key bio- and geo-chemical surface and atmospheric compounds, based on characteristic spectral reflectance features in the visible-near infrared (VNIR) and short-wave infrared (SWIR). Spaceborne missions, a leap in technology, were sparse, starting with the CHRIS/PROBA and EO1/Hyperion missions in the early 2000s, and providing spectroscopy data with limited spectral coverage and/or low data quality in the SWIR. Since 2019, several countries and agencies have successfully launched a number of spaceborne imaging spectroscopy systems into orbit or deployed them on the International Space Station (ISS) such as DESIS, PRISMA, HISUI, GF-5, EnMAP and EMIT. Among these recent missions, the German Environmental Mapping and Analysis Program (EnMAP) stands for its long-term development, sophisticated design with on-board calibration, high data quality requirements, and extensive accompanying science program. EnMAP was launched in April 2022 and, following a successful commissioning phase, started its operational activities in November 2022. The EnMAP mission encompasses global coverage from 80° N to 80° S through on-demand data acquisitions. Data are free and open access with 30 m spatial resolution, a high spectral resolution with a spectral sampling distance of 6.5 nm and 10 nm in the VNIR and SWIR regions respectively, and a high signal-to-noise ratio. In this paper, we aim to present the mission's current status, coverage, science capabilities and performance two years after launch. We show the potential of EnMAP for space-based imaging spectroscopy to operate in various environments, including high and low light levels, dense forests, Antarctic glaciers, and arid agricultural areas. EnMAP enables various applications in fields such as agriculture and forestry, soil compositional, raw materials, and methane mapping, as well as water quality assessment, and snow and ice properties. The results show that EnMAP's performance exceeds the mission requirements, and highlights the significant potential for contribution to scientific exploitation in various geo- and biochemical sciences. EnMAP is also expected to serve as a key tool for the development and testing of data processing algorithms for upcoming global operational missions.

Remote Sensing of Environment↗

USGS2016

A revision in hydrogen isotopic composition of USGS42 and USGS43 human-hair stable isotopic reference materials for forensic science

The hydrogen isotopic composition ( δ 2 H VSMOW-SLAP ) of USGS42 and USGS43 human hair stable isotopic reference materials, normalized to the VSMOW (Vienna-Standard Mean Ocean Water)–SLAP (Standard Light Antarctic Precipitation) scale, was originally determined with a high temperature conversion technique using an elemental analyzer (TC/EA) with a glassy carbon tube and glassy carbon filling and analysis by isotope-ratio mass spectrometer (IRMS). However, the TC/EA IRMS method can produce inaccurate δ 2 H VSMOW-SLAP results when analyzing nitrogen-bearing organic substances owing to the formation of hydrogen cyanide (HCN), leading to non-quantitative conversion of a sample into molecular hydrogen (H 2 ) for IRMS analysis. A single-oven, chromium-filled, elemental analyzer (Cr-EA) coupled to an IRMS substantially improves the measurement quality and reliability of hydrogen isotopic analysis of hydrogen- and nitrogen-bearing organic material because hot chromium scavenges all reactive elements except hydrogen. USGS42 and USGS43 human hair isotopic reference materials have been analyzed with the Cr-EA IRMS method, and the δ 2 H VSMOW-SLAP values of their non-exchangeable hydrogen fractions have been revised: where mUr = 0.001 = ‰. On average, these revised δ 2 H VSMOW-SLAP values are 5.7 mUr more positive than those previously measured. It is critical that readers pay attention to the δ 2 H VSMOW-SLAP of isotopic reference materials in publications as they may need to adjust the δ 2 H VSMOW–SLAP measurement results of human hair in previous publications to ensure all results are on the same isotope-delta scale.

Forensic Science International↗

USGS2024

Pliocene Model Intercomparison Project Phase 3 (PlioMIP3) – Science plan and experimental design

The Pliocene Model Intercomparison Project (PlioMIP) was initiated in 2008. Over two phases PlioMIP has helped co-ordinate the experimental design and publication strategy of the community, which has included an increasing number of climate models and modelling groups from around the world. It has engaged with palaeoenvironmental scientists to foster new data synthesis supporting the construction of new model boundary conditions, as well as to facilitate new data-model comparisons. The work has advanced our understanding of Pliocene climates and environments, enhanced our knowledge regarding the ability of complex climate and Earth System models to accurately simulate climate change, and helped to refine our estimates of how sensitive the climate system is to forcing conditions. In this community protocol paper, we outline the scientific plan for PlioMIP Phase 3 (PlioMIP3). This plan provides the required guidance to participating modelling groups from around the world to successfully set up and perform PlioMIP3 climate model experiments. The project is open to new participants from the scientific community (both from the climate modelling and geosciences communities). In PlioMIP3, we retain the PlioMIP2 Core experiments ( Eoi 400 , E 280 ) and extend the Core requirements to include either an experiment focussed on the Early Pliocene or an alternative Late Pliocene simulation (or both). These additions (a) allow a comparison of Early and Late Pliocene warm intervals and help build research connections and synergy with the MioMIP (Miocene Model Intercomparison Project - also known as DeepMIP-Miocene) and PlioMioVAR projects (Pliocene-Miocene Variability Working Group), and (b) create an alternative time slice simulation for 3.205 Ma (MIS KM5c) through removal of some of the largest palaeogeographic differences introduced between PlioMIP1 and 2 resulting in minimal land-sea mask variations from the modern. In addition, we present ten optional experiments designed to enhance our assessment of climate sensitivity and to explore the uncertainty in greenhouse gas-related forcing. For the first time, we introduce orbital sensitivity experiments into the science plan, as well as simulations incorporating dynamic vegetation-climate feedbacks and an experiment designed to examine the potential significance of East Antarctic Ice Sheet boundary condition uncertainty. These changes enhance palaeo-to-future scientific connections and enable an exploration of the significance of palaeogeographic uncertainties on climate simulations.

Global and Planeatary Change↗