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THE Official Magazine of the OCEANOGRAPHY SOCIETY OceanTE H OFFICIAL MAGAZINEog of the OCEANOGRAPHYraphy SOCIETY CITATION Ortiz, J.D., K.K. Falkner, P.A. Matrai, and R.A. Woodgate. 2011. The changing Arctic Ocean: An introduction to the special issue on the International Polar Year (2007–2008). Oceanography 24(3):14–16, http://dx.doi.org/10.5670/oceanog.2011.49. COPYRIGHT This article has been published inOceanography , Volume 24, Number 3, a quarterly journal of The Oceanography Society. Copyright 2011 by The Oceanography Society. All rights reserved. USAGE Permission is granted to copy this article for use in teaching and research. Republication, systematic reproduction, or collective redistribution of any portion of this article by photocopy machine, reposting, or other means is permitted only with the approval of The Oceanography Society. Send all correspondence to: [email protected] or The Oceanography Society, PO Box 1931, Rockville, MD 20849-1931, USA. down LOADED from www.tos.org/oceanography FROM THE GUEST EDITORS TheC hanging Arctic Ocean An Introduction to the Special Issue on the International Polar Year (2007–2008) BY JOSEPH D. ORTIZ, KELLY K. FALknER, PATRICIA A. MaTRAI, anD REBECCA A. WOODGATE Over the last few decades, the Arctic the western Arctic—could shift from Ocean has experienced profound benthic-dominated to pelagic-dominated changes. Its summer sea ice is shrinking ecosystems, placing growing stress on dramatically, both in thickness and endemic populations. Arctic warming extent. Ever warmer pulses of Atlantic may also affect the global atmosphere’s water are circulating within the Arctic greenhouse gas inventory through basins. Pacific waters are bringing altered CO2 cycling or methane hydrate in record amounts of oceanic heat. stability, whose possible magnitudes Freshwater storage in the Arctic Ocean is are still only poorly known. In addition displaying considerable variability. There to the direct effects on local and global are early signs of ocean acidification, climate, reduced sea ice conditions are and some waters are already corrosive to already opening the Arctic Ocean to carbonate minerals important to marine resource exploration and extraction, life. Surface air temperature and pressure development of new shipping routes, and fields are exhibiting patterns different increased tourism. These activities are from those of the last several decades. focusing attention on maritime safety Looking forward, modeling studies and national and international security. predict that the Arctic could become We must enhance our fundamental seasonally ice-free within a few decades, knowledge of the Arctic system and with profound implications. It seems improve our predictive skills to better inevitable that the Arctic Ocean itself guide future policy decisions. The major will warm, with impacts on local oceanic changes underway in the Arctic impact processes and, coupled with alterations marine ecosystems as well as the people in freshwater cycling, consequences for of the North who depend on them global climate through Arctic-subarctic and are intimately linked to our global linkages. Findings from local studies climate system. Now is clearly an impor- suggest that significant fractions of tant time to keep a finger on the pulse of the Arctic shelves—particularly in the Arctic Ocean. 14 Oceanography | Vol.24, No.3 FROM THE GUEST EDITORS These recent changes and the aimed not just at Arctic experts, but also collective, determined national efforts, possibility of new discoveries in the at those unfamiliar with the Arctic— we gained the first synoptic assessment under-observed polar regions motivated given that an important aspect of this of exchanges between the Arctic and the intense international observational IPY is bringing polar regions to those rest of the world’s ocean, as measured by efforts in the Arctic and Antarctic not intimately involved in them. long-term (multiyear) mooring arrays in during the International Polar Year You will find herein that certainly the key gateways (Beszczynska-Möller et al.; (IPY) of 2007–2008. IPY operations most sustained direct human engage- Münchow et al.). Multiyear ship-based were conducted until 2009 to allow ment in the Arctic is reflected in the observations reveal dramatic changes in observation of complete annual cycles traditions and knowledge of the local the distribution and properties of waters in both the Arctic and the Antarctic. Arctic people (Fienup-Riordan and of the main Arctic basins (McLaughlin National and international efforts were Carmack). Alongside this appreciation et al.), and satellite and modeling data organized by the International Council of change over generations, geological highlight unusual patterns in the atmo- for Science (ICSU) and the World investigations provide a longer-term spheric forcing of the system (Overland). Meteorological Organization (WMO), perspective of regional changes. O’Regan New tools, such as autonomous systems and coordinated by an International et al. provide a current synthesis of measuring ocean physics and relaying IPY Programme Office. This most recent what is known of the Arctic Ocean data via satellite while drifting with IPY marks the fourth time that the world over the past 112–140 million years as the ice (Toole et al.), give us a fresh, community has gathered its scientific it transitioned from a warm, ice-free, broad-scale assessment of Arctic Ocean expertise to assess the state of the Arctic, land-locked sea to the cold, inhospitable change. As our understanding of the with previous efforts taking place in environment that it is today. Polyak and system improves, we can draw on expe- 1882–1883, 1932–1933, and 1957–1958 Jakobsson document the development rience from lower latitudes to foresee (http://ipy.arcticportal.org/about-ipy). of the modern oceanographic circula- increased impacts of wind-driven mixing The six main research themes that united tion features—the Transpolar Drift and internal waves in the currently this latest effort focused on polar region and the Beaufort Gyre—within the last quiescent Arctic Ocean (Rainville status, changes, global linkages, new 0.5 to 0.7 million years. Jennings et al. et al.). Arctic-wide international model frontiers, unique vantage points, and discuss how the retreat of ice from Nares intercomparisons are synthesizing these human dimensions (see Carlson). Strait, in northern Baffin Bay, led to various field efforts to produce a collec- Even at this comparatively early stage, the reconnection of the Arctic and the tive best assessment of Arctic circulation it is clear that the recent IPY signifi- Atlantic Oceans during the warming simulations to enhance their ability cantly enhanced our understanding following the Last Glacial Maximum, to understand Arctic physical change of Arctic and Antarctic systems. As approximately 10,000 years ago, while (Proshutinsky et al.). we outline below, this special issue of St-Onge and Stoner reveal remarkable The impacts of these changes are Oceanography—The Changing Arctic changes in Earth’s magnetic field over the multidisciplinary. Sea ice has histori- Ocean—showcases some of the scientific past 400 years. cally been viewed as a barrier to heat advances and illuminates the consider- Leading up to and through the and mass transport, but that view is now able international investments in the recent IPY, extensive resources have being revised to acknowledge its active 2007–2008 IPY. The volume brings also been aimed at documenting and participation in polar biogeochemical together new and diverse Arctic findings, understanding the “vital parameters” of cycles (Loose et al.). As such, the Arctic stretching across and integrating many the Arctic Ocean. Satellites and drifting marine carbon cycle and exchange of disciplines and including the human buoys allow an updated assessment of sea CO2 between the ocean and atmosphere dimension of the Arctic. The articles are ice state and changes (Perovich). Through appear particularly sensitive to physical Oceanography | September 2011 15 and biological changes (Bates et al.). levels (Moran and Farrell). It is a dream, but not an inaccessible Understanding this complexity requires One major outcome of this IPY is one. The technological components exist conceptual models of biogeochemical recognition of the necessity for the world and are in play in the lower-latitude carbon cycling and climate warming at to observe the Arctic routinely, adapting oceans—the transition to polar environ- various scales (Wassmann and Riegstad). and employing technology now common ments is a difficult, multifaceted chal- Regional differences in summer distribu- at lower latitudes to meet the particular lenge currently under consideration. tions of marine animals in the western challenges of the North. We have a We can and should do more with the Arctic Ocean will likely reflect a new dream for an Arctic observing system necessary resources, and we will. Our balance between northward-moving where gliders equipped with autono- immediate goal thus should be to subarctic fauna, in juxtaposition with mous sensors patrol the Arctic Ocean, define what questions we, as a global Arctic animals that are sea ice depen- collecting information on an array of community, must address in these times dent, and resilient Arctic species (Sigler ocean properties, ferrying data from of rapid Arctic change, and from this et al.). Thus, the diversity of Arctic lone, heavily instrumented subsurface inquiry find an efficient and economi- Ocean biota is reflected in its species
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