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Antarctic Earth System Science in the International Polar Year 2007-2008

Cooper, A. K., P. J. Barrett, H. Stagg, B. Storey, E. Stump, W. Wise, and the 10th ISAES editorial team, eds. (2008). Antarctica: A Keystone in a Changing World. Proceedings of the 10th International Symposium on Antarctic Earth Sciences. Washington, DC: The National Academies Press.

R. E. Bell1

ABSTRACT

The International Polar Year (IPY) 2007-2008 is the largest coordinated effort to understand the polar regions in our lifetime. This international program of science, discovery, and education involves more than 50,000 scientists from 62 nations. The IPY 2007-2008 Antarctic Earth System Science themes are to determine the polar regions’ present environmental status, quantify and understand past and present polar change, advance our understanding of the links between polar regions and the globe, and investigate the polar frontiers of science. There are several key IPY 2007-2008 Earth System Science projects in the Antarctic:

  • POLENET will capture the status of the polar lithosphere through new instrument arrays.

  • ANDRILL will uncover past change using novel drilling technologies.

  • “Plates and Gates” will advance our understanding of the teleconnections between Antarctica and the global climate system.

  • AGAP and SALE-UNITED will study hitherto unsampled subglacial mountains and lakes.

A new era of international collaboration will emerge along with a new generation of Antarctic scientists and a legacy of data and enhanced observing systems.

INTRODUCTION TO IPY 2007-2008

Earth science revolves around the study of our changing planet. IPY 2007-2008 is motivated both by the need to improve our understanding of this changing planet and by a quest to explore still unknown frontiers, especially those beneath the vast Antarctic ice sheet. While intuitively we all appreciate that planetary change happens, as the concept of an international polar year emerged the evidence for rapid and dynamic planetary change was becoming omnipresent. Early in 2002 an ice shelf that had been stable for at least 20,000 years (Domack et al., 2005), the Larsen B Ice Shelf, collapsed in a matter of weeks (Scambos et al., 2004). This ice shelf collapse began to bring together the timescale of planetary change with the more familiar human timescale of days, week, and months.

By 2002 change in the polar regions was undeniable. The surface melt in Greenland was increasing in extent (Steffen et al., 2004), sea ice cover in the Arctic was beginning to decrease notably (Johannessen et al., 1999), the glaciers feeding the Weddell Sea accelerated after the Larsen Ice Shelf collapsed (Rignot et al., 2004; Scambos et al., 2004), and the Amundsen Sea sector of the West Antarctic ice sheet was thinning and accelerating (Joughin et al., 2003; Shepherd et al., 2004). The polar environments were clearly changing, and doing so rapidly. While change is being observed globally, the environmental change at the poles is taking place faster than environmental change anywhere else on the planet. The ramifications of these polar changes reach far beyond the Antarctic and Arctic, because as ice melts, sea levels rise. The need to understand the changes in the polar regions—past, present, and future—is imperative for our global society, the global economy, and the global environment, as well as being a fascinating scientific challenge in its

1

Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York, 10964-8000, USA (robinb@ldeo.columbia.edu).



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Cooper, A. K., P. J. Barrett, H. Stagg, B. Storey, E. Stump, W. Wise, and the 10th ISAES editorial team, eds. (2008). Antarctica: A Keystone in a Changing World. Proceedings of the 10th International Symposium on Antarctic Earth Sciences. Washington, DC: The National Academies Press. Antarctic Earth System Science in the International Polar Year 2007-2008 R. E. Bell1 ABSTRACT INTRODUCTION TO IPY 2007-2008 The International Polar Year (IPY) 2007-2008 is the largest Earth science revolves around the study of our changing coordinated effort to understand the polar regions in our planet. IPY 2007-2008 is motivated both by the need to lifetime. This international program of science, discovery, improve our understanding of this changing planet and by and education involves more than 50,000 scientists from 62 a quest to explore still unknown frontiers, especially those nations. The IPY 2007-2008 Antarctic Earth System Science beneath the vast Antarctic ice sheet. While intuitively we all themes are to determine the polar regions’ present environ- appreciate that planetary change happens, as the concept of mental status, quantify and understand past and present polar an international polar year emerged the evidence for rapid change, advance our understanding of the links between and dynamic planetary change was becoming omnipresent. polar regions and the globe, and investigate the polar fron- Early in 2002 an ice shelf that had been stable for at least tiers of science. There are several key IPY 2007-2008 Earth 20,000 years (Domack et al., 2005), the Larsen B Ice Shelf, System Science projects in the Antarctic: collapsed in a matter of weeks (Scambos et al., 2004). This ice shelf collapse began to bring together the timescale of • POLENET will capture the status of the polar litho- planetary change with the more familiar human timescale of sphere through new instrument arrays. days, week, and months. • ANDRILL will uncover past change using novel By 2002 change in the polar regions was undeniable. drilling technologies. The surface melt in Greenland was increasing in extent • “Plates and Gates” will advance our understanding (Steffen et al., 2004), sea ice cover in the Arctic was begin- of the teleconnections between Antarctica and the global ning to decrease notably (Johannessen et al., 1999), the climate system. glaciers feeding the Weddell Sea accelerated after the Larsen • AGAP and SALE-UNITED will study hitherto Ice Shelf collapsed (Rignot et al., 2004; Scambos et al., unsampled subglacial mountains and lakes. 2004), and the Amundsen Sea sector of the West Antarctic ice sheet was thinning and accelerating (Joughin et al., A new era of international collaboration will emerge 2003; Shepherd et al., 2004). The polar environments were along with a new generation of Antarctic scientists and a clearly changing, and doing so rapidly. While change is being legacy of data and enhanced observing systems. observed globally, the environmental change at the poles is taking place faster than environmental change anywhere else on the planet. The ramifications of these polar changes reach far beyond the Antarctic and Arctic, because as ice melts, sea levels rise. The need to understand the changes in the polar regions—past, present, and future—is imperative for our global society, the global economy, and the global environ- 1 Lamont-Doherty Earth Observatory of Columbia University, Palisades, ment, as well as being a fascinating scientific challenge in its New York, 10964-8000, USA (robinb@ldeo.columbia.edu). 7

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8 ANTARCTICA: A KEYSTONE IN A CHANGING WORLD own right. This overwhelming sense of rapid and increasing ice for 90 days to the relative safety of open water. Weyprecht change, and what we can learn from it, especially in the polar was acutely aware that the systematic observations necessary regions where the change is fastest, is one of the major moti- to advance the understanding of the fundamental problems of vations for the development of the IPY (Albert, 2004). meteorology and geophysics were impossible for men haul- Beyond the sense of planetary change, discovery is a ing sledges across the ice and struggling to survive. His frus- keen motivator. In the 1800s exploration was conducted tration with the inability to understand polar phenomena with by teams of men pressing for the poles, led by Nansen, the data from a single national expedition is captured in his Amundsen, Scott, and Shackleton. Nansen captured the “Fundamental Principles of Arctic Research” (Weyprecht, essence of geographically motivated exploration, noting that 1875). He noted that “whatever interest all these observations humankind’s spirit “will never rest till every spot of these may possess, they do not possess that scientific value, even regions has been trod upon” (Nansen and Sverdrup, 1897). supported by a long column of figures, which under other Today we seek to push the frontiers of our knowledge of circumstances might have been the case. They only furnish us processes, rather than geographic frontiers. The community with a picture of the extreme effects of the forces of Nature remains intensely motivated by Nansen’s second restless in the Arctic regions, but leave us completely in the dark with quest, which is to seek knowledge “till every enigma has respect to their causes.” been solved.” While Nansen sought to understand the circu- Weyprecht believed that the systematic successful study lation in the Arctic Ocean, today we see major opportunities of the polar regions and large-scale polar phenomena by a for scientific discovery in Antarctic Earth science. Discovery single nation was impossible. He argued that fixed stations is the second motivation for this IPY. The frontiers are no where coordinated observations could be made were neces- longer the geographic poles but the regions and processes sary for consistency of measurements. Weyprecht’s insights hidden by kilometers of ice and water. were central to the planning and execution of the first IPY. Propelled forward by the sense of planetary change and A realization of Weyprecht’s vision, the first IPY (1882- a sense of discovery, IPY 2007-2008 will be the largest inter- 1883) involved 12 countries launching 15 expeditions to the nationally coordinated research program in 50 years, actively poles: 13 to the Arctic and 2 to the Antarctic, using coal- and engaging over 50,000 scientists from 62 nations. The result steam-powered vessels (Figure 1). At each station a series of of a five-year community-wide planning process, the IPY 2007-2008 will be an intensive period of interdisciplinary science focused on both polar regions—the Antarctic and the Arctic. The projects of the IPY 2007-2008 focus on decipher- ing these processes of change in the polar regions and their linkages with the rest of the globe while also exploring some of the final frontiers. FRAMEWORK Today in our global interconnected world, “year” events occur at a frenetic pace. For example, 2002 was the U.N. International Year of Mountains and 2005 was the U.N. Year of Physics. These U.N.-sponsored events tend to focus on celebration, awareness, and education. For instance, in paral- lel with the IPY 2007-2008, Earth scientists have developed the U.N. International Year of Planet Earth, a celebration of the role of Earth science in society. Awareness, celebration, and education have consistently been a key facet of all IPYs since 1882-1883, but the central framework for the polar years has always been to facilitate collaborative science at a level impossible for any individual nation. The concept of collaborative international polar sci- ence focused on a specific period was developed by Lt. Karl Weyprecht, an Austrian naval officer. Weyprecht was a scien- FIGURE 1 First International Polar Year. Top: Norwegian ship tist and co-commander of the Austro-Hungarian North Pole in the ice, Kara Sea (from Steen [1887]). Bottom: Observer mak- Expedition that set off in 1872 in a three-masted schooner, ing temperature observations at Fort Conger, 1882 (from Greely the Admiral Tegetthoff. The expedition returned two years [1886]). later without the schooner. The expedition had abandoned the SOURCE: See http://www.arctic.noaa.gov/aro/ipy-1/US-LFB- ship frozen into the pack ice and hauled sledges over the pack P4.htm.

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9 BELL FIGURE 2 Second International Polar Year. Left: Aircraft in Antarctica (from the Ohio State University Archives, Papers of Admiral Richard E. Byrd, #7842_18). Right: Launching a weather balloon in northern Canada (from the University of Saskatchewan Archives, 1931). regular observations were recorded with pencil and paper, was the brainchild of a small number of eminent physicists, from meteorology to Earth’s magnetic field variations (Fig- including Sydney Chapman, James Van Allen, and Lloyd ure 1). Beyond the advances to science and geographical Berkner. These physicists realized that the technology exploration, a principal legacy of the first IPY was setting developed during World War II, such as rockets and radar, a precedent for international science cooperation. The clear could be deployed to advance science. Sixty-seven nations gap between Weyprecht’s vision and the outcomes was that participated in the IGY. The IGY’s research, discoveries, and the data were never fully integrated and analyzed together vast array of synoptic observations set the stage for decades (Wood and Overland, 2006). of geophysical investigations. Data collected from ships were During the first IPY (1882-1883) the Brooklyn Bridge used subsequently to advance the theory of plate tectonics, opened in New York City, five years before the Eiffel Tower while satellites detected the Van Allen Radiation Belt. Seis- opened in Paris. Fifty years later the second IPY (1932- mic measurements collected along geophysical traverses 1933) began, and this was the year the Empire State Build- measured the thickness of the Antarctic ice sheet, enabling ing opened in New York City. Routine flights by aircraft and the first estimates of Antarctica’s ice mass. Emerging from wireless communication were both now possible. During the IGY was the Scientific Committee on Antarctic Research the second IPY, 40 nations conducted Arctic research focus- (SCAR) in 1958 and the Antarctic Treaty in 1961. Permanent ing on meteorology, magnetism, atmospheric science, and stations were established for the first time in Antarctica as a ionospheric physics. Forty permanent observation stations direct result of the IGY. were established in the Arctic. The U.S. contribution to the At the end of the IGY, Hugh Odishaw, executive direc- second IPY was the second Byrd Antarctic expedition. The tor of the U.S. National Committee, noted, “We have only Byrd expedition established the first inland research station, scratched the surface of our ignorance with respect to a winter-long meteorological station on the Ross Ice Shelf Antarctic. . . . There is at hand an unparalleled situation at the southern end of Roosevelt Island. Scientists employed for stimulating the best in man” (Odishaw, 1959). Having aircraft to extend the range of their observations and for the scratched the surface of Antarctica, scientists and engineers first time received data transmitted back from balloons as of 1958 handed the baton to our generation to bring together they drift upward, allowing the first vertical sampling of the scientists and engineers to understand the role the poles polar atmosphere (Figure 2). play in our rapidly changing world. It is for us to explore The third IPY expanded beyond the polar regions, the remaining frontiers using the cutting-edge technologies quickly becoming global. This polar year was renamed the available to us today: jet aircraft, ships, satellites, lasers, the International Geophysical Year (IGY) and ran from July 1, Global Positioning System (GPS), advanced communica- 1957, to December 31, 1958 (see Figure 3). Coincident with tions, computers, numerical modeling, passive seismics, the groundbreaking for the Sydney Opera House, the IGY autonomous observatories, and novel coring technologies.

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10 ANTARCTICA: A KEYSTONE IN A CHANGING WORLD FIGURE 3 International Geophysical Year 1957-1958. Left: Geophysical traverse vehicle collecting seismic data at Byrd Station, West Ant- arctica (from http://www.nas.edu/history/igy/seismology.html). Right: Sputnik, the first satellite launched into space (image from NASA). IPY 2007-2008 PLANNING PROCESS tidisciplinary traverses along all the major ice divides of East Antarctica. The SCAR delegates supported a proposal The development of the IPY 2007-2008 began with an to develop a “celebration.” In late 2002 the U.S. National extended period of community education with scientists Academy of Sciences Polar Research Board convened a studying the accounts of the previous IPYs and discuss- one-day international workshop addressing the question of ing the results. The concept of another polar year emerged whether an IPY was an applicable framework for science through discussions among communities and with funding in 2007. Workshop participants strongly supported the IPY agencies. Websites documenting the contributions of the concept, and within the next six months the U.S. National first three IPYs were launched. These discussions were first Academies began the planning process in the United States documented in SCAR meeting reports in 2000. At the 2000 (Albert, 2004). Simultaneously Chris Rapley and Robin Bell SCAR meeting in Tokyo, K. Erb, president of the Council submitted a proposal to the International Council for Science of Managers of National Antarctic Programs, reported on (ICSU) Executive Committee to form a planning committee discussions to “prepare for recognition of the 50th Anni- for the IPY. ICSU approved the proposal and the Planning versary of the International Polar Year.” One year later the Committee met for the first time in August 2003. The plan- discussions were still on the margins, with a short note in ning had moved past a celebration to setting a science agenda the report from the SCAR executive meeting, under the title for a major international interdisciplinary effort (Figure 4). “Any Other Business.” Again the focus was on celebration, Independently a group at the World Meteorological not action. The Neumayer International Symposium in 2001 Organization (WMO), a sponsor of the earlier IPYs, had provided a further opportunity for the community to discuss begun considering involvement in the proposed IPY 2007- the impending 50th anniversary of the IGY and the 125th 2008. WMO joined the ICSU planning process in an advi- anniversary of the first IPY, but the focus had not yet moved sory role. With the completion of the framework document beyond celebration plans. (Rapley and Bell, 2004), the ICSU Planning Committee’s The first concrete plan for IPY 2007-2008 science was work was complete. Together ICSU and WMO formed a presented by Heinz Miller at the 2002 SCAR meeting in new joint steering group called the Joint Committee, with Shanghai (SCAR, 2002). Miller proposed a series of mul-

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11 BELL FIGURE 4 Emergence of International Polar Year 2007-2008 as documented in SCAR reports. Usage of the terms “IPY” and “International Polar Year” in SCAR reports from 1998 to 2007. Discussion focused on a celebration until 2002, when the emphasis became science. two co-chairs with representation from ICSU and WMO. A 1. Status: Determine the present environmental status competition for an IPY International Program Office (IPO) of the polar regions; was announced, and the successful bid was submitted by the 2. Change: Quantify and understand past and present British Antarctic Survey. An executive director for the IPY natural, environmental, and social change in the polar regions was hired, and the IPY 2007-2008 moved from the design and improve projections of future change; phase to the implementation phase. 3. Global Linkages: Advance understanding on all The implementation phase required that the Joint Com- scales of the links and interactions between the polar regions mittee develop a process to review the proposed work for the and the rest of the globe and of the controlling processes; IPY 2007-2008 and develop a science plan. In due course 4. New Frontiers: Investigate the frontiers of science the Joint Committee reviewed over 300 proposals that form in the polar regions; the core of the IPY Science Program. The committee worked 5. Vantage Point: Use the unique vantage point of the with the authors of proposals to ensure that many smaller polar regions to develop and enhance observatories from the projects could be accommodated under larger umbrella interior of Earth to the sun and the cosmos beyond; and projects, like CASO (Climate of Antarctica and the South- 6. The Human Dimension: Investigate the cultural, ern Ocean), which includes several smaller projects that historical, and social processes that shape the sustainability started as Letters of Intent, but all contribute to the overall of circumpolar human societies and identify their unique CASO goal. The aim was to encourage development of a contributions to global cultural diversity and citizenship. relatively small number of large projects that would “make a difference.” The first three themes—Status, Change, and Global Development of the project proposals was not top-down Linkages—capture the changing planet, with an emphasis on but a direct result of the community input. Taken together the changing climate at all times and scales (Figure 5 as the red 300 or so projects can be seen to make up a comprehensive triangle, or delta symbol). The majority of IPY 2007-2008 and integrated science plan, which was published by the projects address these themes. The fourth—New Frontiers, Joint Committee in 2007 (Allison et al., 2007). In March or the exploration and discovery theme—has its largest 2007 the polar year opened around the globe with events projects in Antarctic Earth sciences as predicted by Odishaw in over 30 nations signaling the beginning of two years of at the close of the IGY. These frontiers in Earth science are intensive polar observation and analysis. This current year primarily beneath the ice sheet or beneath the ocean floor is just the beginning. (blue box at the base of Figure 5). The Vantage Point theme encompasses everything from observatories to examine the inner core to telescopes monitoring distant galaxies. The THEMES Human Dimension theme of this IPY 2007-2008 has a strong This four-year grassroots planning process defined six presence in the north but is not developed in the south due to scientific themes that are the essential framework for IPY the absence of a large permanent human population there. 2007-2008:

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12 ANTARCTICA: A KEYSTONE IN A CHANGING WORLD FIGURE 5 Left: Schematic of major IPY 2007-2008 themes. Right: Mapping major Antarctic Earth science projects. MAJOR INTERNATIONAL POLAR YEAR EARTH AGAP/PANDA projects, which target the origin, evolution, SCIENCE PROJECTS and setting of subglacial lakes and the Gamburtsev subgla- cial highlands and the structure of the Dome A region, are The principal IPY 2007-2008 Antarctic Earth science proj- both clear examples of the New Frontiers theme. As the ects address change and all its components and exploration POLENET observatories will include components capable of of new frontiers. The Antarctic Earth science components examining structure deep within Earth’s interior, that project of the IPY 2007-2008 are primarily found within the Earth, is also emblematic of the Vantage Point theme. land, and ice sector of the framework (Allison et al., 2007). Twelve projects fall into the category of Antarctic Earth sci- POLENET ences (Table 1). Many of these projects are inherently interdisciplinary. POLENET is a consortium of scientists from 24 nations that This paper highlights five large projects that capture the will deploy a diverse suite of geophysical instruments aiming breadth of the IPY 2007-2008 Earth science programs, both at interactions of the atmosphere, oceans, polar ice sheets, in terms of the time periods they address and in terms of and Earth’s crust and mantle (Figure 6). The POLENET their geographic locations. POLENET (Polar Earth Observ- teams will be deploying new GPS instruments, seismic ing Network) will be implemented in both polar regions and stations, magnetometers, tide gauges, ocean-floor sensors, will capture the tectonic and isostatic status of the Antarctic and meteorological recorders. The science program of the plate. POLENET is the major Antarctic Earth science project POLENET consortium will investigate polar geodynamics; under the Status theme. Earth’s magnetic field, crust, mantle, and core structure and ANDRILL (Antarctic Geologic Drilling), which in dynamics; and systems-scale interactions of the solid Earth, late 2006 recovered the longest rock core in Antarctica, is cryosphere, oceans, and atmosphere. Activities will focus a highly visible element of the Antarctic Climate Evolution on the deployment of autonomous observatories at remote (ACE) program, which integrates modeling studies and sites on the continents and offshore, coordinated with mea- observational data from the Antarctic margin to resolve the surements made at permanent stations and by satellite cam- continent’s paleoenvironmental history. ANDRILL together paigns. Geophysical observations made by POLENET will with ACE clearly illustrate both the Change theme and the contribute to many branches of geoscience and glaciology. Global Linkages theme, as they examine the teleconnec- For example, sea-level and ice-sheet monitoring can be fully tions between Northern and Southern Hemisphere climate modeled only when measurements of solid Earth motions change. are incorporated. Both plate tectonic and paleoclimate stud- “Plates and Gates,” by focusing on the tectonic and ies benefit from crustal deformation results. POLENET’s sedimentary formation of ocean gateways that are critical for approach to install autonomous observatories collecting controlling major water masses and global change, is a clear coordinated measurements captures Weyprecht’s vision of example of an investigation of the global linkages between coordinated observations from fixed stations. polar processes and global climate. SALE-UNITED and the

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13 BELL TABLE 1 Antarctic Earth Science IPY 2007-2008 Proposals from Scope of Science Report Proposal No. and Short Title Long Title 67 AGAP Antarctica’s Gamburtsev Province; origin, evolution, and setting of the Gamburtsev subglacial highlands; exploring an unknown territory 256 ANDRILL Antarctic Geologic Drilling: Antarctic continental margin drilling to investigate Antarctica’s role in global environmental change 109 Rift System Dynamics Geodynamics of the West Antarctic Rift System and its implications for the stability of the West Antarctic ice sheet 77 Plates and Gates Plate tectonics and polar ocean gateways 152 IDEA Ice Divide of East Antarctica: Trans-Antarctic Scientific Traverses expeditions 185 POLENET Polar Earth Observing Network 886 USGS U.S. Geological Survey: Integrated Research 54 ACE Antarctic Climate Evolution 97 ICECAP Investigating the Cryospheric Evolution of the Antarctic Plate 33 ANTPAS Antarctic Permafrost and Soils 313 PANDA The Prydz Bay, Amery Ice Shelf, and Dome-A Observatories 42 SALE-UNITED Subglacial Antarctic Lake Environments-Unified International Team for Exploration and Discovery FIGURE 6 Left: Location of planned POLENET sites in Antarctica. Stars = New stations. Center: Deploying remote GPS station. Right: Deploying remote seismic station. SOURCE: www.polenet.org. ANDRILL and became an integral part of the IPY 2007-2008 program. ANDRILL is a scientific drilling project investigating Ant- ANDRILL is the latest of a series of floating-ice-based arctica’s role in global climate change over the last 60 million drilling projects on the Antarctic margin, complementing years. Employing new drilling technology designed specifi- ship-based projects that date back to Deep Sea Drilling cally for ice-shelf conditions as well as state-of-the-art core Project Leg 28 in 1972 (Figure 7). ANDRILL is a multina- analysis and ice-sheet modeling, ANDRILL addresses four tional collaboration of more than 200 scientists, students, scientific issues: (1) the history of Antarctica’s climate and and educators from Germany, Italy, New Zealand, and the ice sheets; (2) the evolution of polar biota and ecosystems; United States; it is also the largest Antarctic Earth science (3) the timing and nature of major tectonic and volcanic epi- IPY 2007-2008 project targeting the Change and global sodes; and (4) the role of Antarctica in Earth’s ocean-climate linkages themes. system. ANDRILL’s goal is to drill a series of holes in the ANDRILL is an example of a major international project McMurdo Sound area in regions that have previously been that developed in parallel with the IPY 2007-2008 planning inaccessible to ship-based drilling technologies. The strati-

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14 ANTARCTICA: A KEYSTONE IN A CHANGING WORLD FIGURE 7 Top left: ANDRILL drill rig in the McMurdo Sound. Top right: Conducting core analysis on site. Bottom: Core in core trays. SOURCE: Images are from www.andrill.org. graphic records retrieved from these boreholes will cover water masses. Ocean gateways are the deepwater passage- critical time periods in the development of Antarctica’s major ways that form as continents rift apart and that are destroyed ice sheets. The sediment cores will be used to construct an when ocean basins close (Figure 8). As part of the global overall glacial and interglacial history for the region, includ- ocean circulation, water masses move through these pas- ing documentation of sea-ice coverage, sea level, terrestrial sageways, and major shifts in the ocean gateways produce vegetation, and meltwater discharge events. The cores will changes in the transport of heat, salt, and nutrients. These also provide a general chronostratigraphic framework for changes in global ocean circulation may trigger changes in regional seismic studies to help unravel the area’s complex global climate. Plates and Gates will establish detailed tec- tectonic history. The first borehole was drilled in 2006-2007, tonic, geodynamic, sedimentary, and paleotopographic his- and drilling the second borehole will begin in the 2007-2008 tories of major oceanic gateways, providing basic constraints field season. for global climate modeling. In Antarctica, key areas are the Drake Passage and the former Tasman Gateway, the last bar- riers to the establishment of the Antarctic Circumpolar Cur- Plates and Gates rent. The Antarctic Circumpolar Current is the fundamental “Plates and Gates” is a multidisciplinary project aimed at vehicle for mass flux between the Pacific, Atlantic, and understanding key polar oceanographic gateways for major Indian oceans and has the largest flux of all the globe’s ocean

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15 BELL FIGURE 8 Plates and Gates. Left: Major ocean gateways influencing ocean circulation (from R. Livermore, British Antarctic Survey). Right: Alfred Wegner Institute’s R/V Polarstern (from K. Gohl, Alfred Wegner Institute). currents. The establishment of this large global ocean current highest plateau of the Antarctic ice sheet. While both the age has been suggested as one of the major triggers for the onset and origin of the Gamburtsev Mountains in the framework of Antarctic glaciation (Kennett, 1977). Field projects and of Antarctic and Gondwana tectonics has been a matter of modeling will be linked from the beginning to yield a model considerable speculation, this unusual mountain range has of the present status of water mass exchange in these regions, been advanced as the nucleation point for two continental- development of “gateway flow dynamics models” as well scale glaciations, one in the late Paleozoic and one in the as a new range of high-resolution paleooceanographic and Cenozoic. The Gamburtsev Subglacial Mountains today are paleoclimate models. Plates and Gates will employ a coupled encased beneath 1 to 4 km of continental ice, but their role ocean atmosphere general circulation model to examine the in ice-sheet dynamics, specifically as the nucleation point for impact of opening and closing of high- and low-latitude continental-wide glaciation, remains speculative given our gateways on Eocene-Oligocene and Pliocene-Pleistocene lack of knowledge about their age and origin. climate changes. This project started in January 2007 with AGAP will use aircraft and surface instrumentation to an expedition onboard the R/V Polarstern. collect major new datasets, including gravity, magnetics, ice radar, and other geological observations. The airborne team (GAMBIT) will acquire an extensive new airborne dataset, AGAP and PANDA including gravity, magnetics, ice thickness, synthetic aper- AGAP and PANDA together are a multinational, multidis- ture radar images of the ice-bed interface, near-surface and ciplinary aerogeophysical, traverse, and passive seismic deep internal layers, and ice surface elevation. The nested instrumentation effort to explore East Antarctic ice-sheet survey design will include a dense high-resolution survey history and the lithospheric structure of the Gamburtsev over Dome A augmented by long regional lines to map the Subglacial Mountains (see Figure 9). AGAP and PANDA tectonic structures. The interpretation of these datasets will together assembled scientists from six nations to launch advance our understanding of ice-sheet dynamics, subglacial the IPY 2007-2008 Gamburtsev Subglacial Mountains lakes, and Antarctic tectonics. The seismic team (GAMSEIS) Expedition. The Gamburtsev Subglacial Mountains are a will deploy portable broadband seismographs to examine the major mountain range, larger than the Alps but virtually seismic structure of the crust and upper mantle. The PANDA unexplored since they were discovered during the IGY in transect from Prydz Bay-Amery Ice Shelf-Lambert Glacier 1958. The Gamburtsev Subglacial Mountains are a 400-km- Basin-Dome A covers an interconnected ocean, ice-shelf, and wide elevated massif rising 2000-3000 m above the regional ice-sheet system, which plays a very important role in East topography and resting beneath the ice divide at Dome A, the Antarctica mass balance, sea level, and climate change.

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16 ANTARCTICA: A KEYSTONE IN A CHANGING WORLD FIGURE 9 Top: Aerogeophysical Twin Otter in East Antarctica. Bottom: AGAP survey design over ice surface (yellow grid). SOURCE: Images are from M. Studinger, Lamont- Doherty Earth Observatory. SALE-UNITED these lakes. The Recovery Lakes appear to be triggering the onset of rapid ice flow into the Recovery Ice Stream (Bell et SALE-UNITED is a federation of interdisciplinary research- al., 2007). Seismic data collected by the U.S.–Norwegian tra- ers who will conduct expeditions to explore all facets of verse team will provide insights into the volume of subglacial subglacial lake environments under the New Frontiers theme water, while the airborne geophysics will constrain the flux during the IPY 2007-2008 (Figure 10). The SALE-UNITED of ice and water through the system. Additionally, the SALE- research and exploration project will investigate subglacial UNITED group will conduct genomic studies of accreted ice lake environments of differing ages, evolutionary histories, and modeling of lake stability. Together these projects will and physical settings. These comparative studies will provide advance our understanding of the subglacial lake environ- a holistic view of subglacial environments over millions of ment and the role lakes play in ice-sheet stability. years and under differing climatic conditions. Included in the SALE-UNITED IPY 2007-2008 projects will be the drill- AN INTEGRATED VISION FOR ANTARCTIC EARTH ing into Lake Vostok in 2008-2009, acquisition of surface SCIENCE IN THE IPY 2007-2008 geophysics over Lake Ellsworth in West Antarctica and Lake Concordia near Dome Concordia, and acquisition of both The five major projects described above capture the major airborne and surface geophysics over the Recovery Lakes IPY 2007-2008 themes that were defined in the planning in Queen Maud Land. Each one of these projects represents process. Together they illustrate the breadth of the Antarc- a major advance in the study of subglacial lakes. The suc- tic Earth science programs for the IPY 2007-2008. While cessful recovery of water from drilling into Lake Vostok will at first glance these projects may appear to be narrowly provide key new insights into the fundamental questions as focused on climate, they capture the entire scope of major to the basic nature of the water in the lakes and whether life Antarctic geophysical events (Table 2). For example, AGAP can be supported in the water column. Lakes Ellsworth and and PANDA will be targeting the basic cratonic structure Concordia are also targeted for sampling. The surface geo- of East Antarctica, structures that likely formed during the physics acquired during IPY 2007-2008 will provide seismic assembly of Rodinia and other key events early in the history constraints on the volume of water and the processes within of the Antarctic continent. Plates and Gates focuses on the

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17 BELL break-up of Gondwana and the subsequent formation of the ocean gateways between continental fragments. Both AGAP and POLENET will contribute to resolving the history of extension in the Ross Sea, while controls on Transantarctic Mountains uplift will be elucidated by both Plates and Gates and ANDRILL. The origin, history, and stability of the Ant- arctic ice sheets will be addressed by all these projects. OUTSTANDING CHALLENGES As of this writing we are still at an early stage of the IPY 2007-2008, less than six months after the official opening in Paris and around the globe on March 1, 2007. Since the iden- tification of funding for national components of IPY 2007- 2008–approved projects is still ongoing in many countries, it remains difficult to fathom the full breadth of the IPY 2007- 2008. But several hundred million dollars of new money for polar science is already available, and more is likely. Even at this early stage it is useful to consider the pitfalls that other IPYs have encountered that prevented them from realizing their full potential. The results of the first IPY were never fully realized because each nation worked to publish their data individually. The data were not openly shared, and long-term collaboration between nations did not materialize. In our more electronically connected world there is little excuse for data not to be openly shared and deposited in the appropriate data repository so that future generations can make use of this precious resource. Building collaborations within a discipline is simple. The challenge for this IPY 2007-2008 is to establish long- lasting, effective working relationships across disciplines. Many of the projects contain the seeds of these difficult multidisciplinary relationships, whether between modelers and field scientists or between biologists and geophysicists. These interactions must be fostered and developed. Col- laborations built on shared data and shared passions in Earth systems are essential. Interdisciplinary science is difficult, but it will be the only way Earth science will remain relevant FIGURE 10 Top: SALE-UNITED. Location of subglacial lakes to society, and it is the only way to gain the full return from (from M. Studinger, http://www.ldeo.columbia.edu/~mstuding/ our investment. True, open interdisciplinary collaboration vostok.html) Bottom: Traverse vehicles for U.S.–Norwegian tra- will serve to advance our understanding of the poles and the verse of the Recovery Lakes (from Norwegian Polar Institute). role they play in our planetary system. TABLE 2 Five Major Antarctic Geophysical Events Targeted by IPY 2007-2008 Programs Uplift of the Origin, History, Status, Major Formation of East Breakup of Extension of the Transantarctic Stability of Antarctic Ice Event Antarctic Craton Gondwana Ross Sea Mountains Sheets IPY AGAP, Plates and Gates ANDRILL, ANDRILL, AGAP, PANDA, 2007-2008 PANDA POLENET Plates and Gates ANDRILL, Programs Plates and Gates, POLENET, SALE-UNITED

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18 ANTARCTICA: A KEYSTONE IN A CHANGING WORLD ANTICIPATED OUTCOMES Joughin, I., E. Rignot, C. E. Rosanova, B. K. Lucchitta, and J. Bohlander. 2003. Timing of recent accelerations of Pine Island Glacier, Antarctica. This IPY 2007-2008 marks the beginning of a new era in Geophysical Research Letters 30(13):1706. Kennett, J. P. 1977. Deep-sea drilling contributions to studies of evolution polar science that will routinely involve cooperation between of Southern-Ocean and Antarctic glaciation. Antarctic Journal of the a wide range of research disciplines from geophysics to ecol- United States 12(4):72-75. ogy. While much of our science today is international, the Nansen, F., and O. N. Sverdrup. 1897. Farthest North: Being the Record of IPY 2007-2008 is truly the largest international scientific a Voyage of Exploration of the Ship “Fram” 1893-96, and of a Fifteen endeavor of any kind that most of us will ever witness. Just Months’ Sleigh Journey by Dr. Nansen and Lieut. Johansen. New York: Harper. as many of today’s leaders in science and engineering entered Odishaw, H. 1959. “The Meaning of the International Geophysical Year,” these fields because of the IGY, the next generation will be U.S. President’s Committee on Information Activities Abroad (Sprague captivated by the powerful science projects of the IPY 2007- Committee) Records, 1959-1961, Box 6, A83-10, Dwight D. Eisen- 2008. The IPY 2007-2008 will open new frontiers, specifi- hower Library, Abilene, Kansas. cally East Antarctica and the subglacial environment, to the Rapley, C., and R. E. Bell. 2004. A Framework for the International Polar Year 2007-2008. Paris: ICSU. international scientific community. From the IPY 2007-2008 Rignot, E., G. Casassa, P. Gogineni, W. Krabill, A. Rivera, and R. Thomas. will emerge new collaborative frameworks for science that 2004. Accelerated ice discharge from the Antarctic Peninsula follow- will continue to enable each of us to accomplish more than ing the collapse of Larsen B Ice Shelf. Geophysical Research Letters we could have accomplished as individual scientists or as 31(18). individual nations. Scambos, T. A., J. A. Bohlander, C.A. Shuman, and P. Skvarca. 2004. Gla- cier acceleration and thinning after ice shelf collapse in the Larsen B embayment, Antarctica. Geophysical Research Letters 31(18). REFERENCES SCAR. 2002. Scientific Committee on Antarctic Research Bulletin, Cam- bridge, Scientific Committee on Antarctic Research 149:1-16. Albert, M. R. 2004. The International Polar Year. Science 303(5663): Shepherd, A., D. Wingham, A. Payne, and P. Skvarca. 2004. Warm ocean 1437. is eroding West Antarctic ice sheet. Geophysical Research Letters Allison, I. B. M. et al. 2007. The scope of science for the International Polar 31(23). Year 2007-2008. World Meterologic Organization Technical Document Steen, A. S. 1887. Die internationale Polarforschung, 1882-1883. No. 1364, 81 pp. Geneva: World Meterologic Organization. Beobachtungs-Ergebnisse der Norwegischen Polarstation Bossekop in Bell, R. E., M. Studinger, C. A. Shuman, M. A. Fahnestock, and I. Joughin. Alten. Christiania: Grödahl & Sons. 2 vols. 2007. Large subglacial lakes in East Antarctica at the onset of fast- Steffen, K., S. V. Nghiem, R. Huff, and G. Neumann. 2004. The melt anom- flowing ice streams. Nature 445(7130):904-907. aly of 2002 on the Greenland ice sheet from active and passive micro- Domack, E., D. Duran, A. Leventer, S. Ishman, S. Doane, S. McCallum, wave satellite observations. Geophysical Research Letters 31(20). D. Amblas, J. Ring, R. Gilbert, and M. Prentice. 2005. Stability of the Weyprecht, L. K. 1875. Scientific work of the Second Austro-Hungarian Larsen B Ice Shelf on the Antarctic Peninsula during the Holocene Polar Expedition, 1872-4. Journal of the Royal Geographical Society epoch. Nature 436(7051):681-686. of London 45:19-33. Greely, A. W. 1886. Report on the Proceedings of the United States expe- Wood, K. R., and J. E. Overland. 2006. Climate lessons from the first Inter- dition to Lady Franklin Bay, Grinnell Land. Washington, D.C.: U.S. national Polar Year. Bulletin of the American Meteorological Society Government Printing Office. 87(12):1685-1697. Johannessen, O. M., E. V. Shalina, V. Elena, and M. W. Miles. 1999. Sat- ellite evidence for an Arctic sea ice cover in transformation. Science 286(5446):1937-1939.