Antarctica

by

Peter Convey

• LAST REVIEWED: 15 January 2019
• LAST MODIFIED: 15 January 2019
• DOI: 10.1093/obo/9780199363445-0109

Introduction

Antarctica originally formed part of the southern supercontinent, Gondwana, and its fossil record shows that the continent hosted cool temperate and even subtropical forests, dinosaurs, early mammals, and many other biota, despite lying at high southern paleolatitudes for over 100 My. The Antarctica of today is a continent of extremes, inspiring awe, trepidation, and superlatives from those privileged to experience it. It is certainly a forbidding place, more than twice the area of Australia, distant and isolated from other southern continents, with around 0.2 percent of its area ever exposed from permanent ice and snow and covered on average with ice more than 2 kilometers thick. In winter, the surface of an area of ocean of approximately the same size as the continent freezes around it, and throughout the year ice is one of the major drivers of physical and biological processes in the Southern Ocean. Antarctica is also distinct among the Earth’s continents, being the only one not to have ever had a natural human population, and only being discovered and explored over the last one to two centuries. Even now, the human population is limited to the temporary residents of national research stations (about five thousand in summer and one thousand in winter), augmented by thirty to forty thousand mostly ship-based tourist visitors in the austral summer. At least to human perception, the environments of the polar regions are challenging to life. Organisms that live on land in Antarctica today must survive chronic, highly variable and extreme environmental stresses, in particular low temperatures, desiccation, high winds, and a harsh radiation climate. At latitudes beyond the Antarctic Circle, extreme seasonality is driven by the sun remaining permanently below the horizon for up to several months during winter and, conversely, above the horizon in summer. In winter terrestrial habitats experience extremely low air temperatures, typically −40 to −60°C or lower (the lowest instrumentally recorded temperature on Earth is −89.2°C, at Vostok Station on the Antarctic polar plateau). As well as its extreme climate, parts of Antarctica, in particular the Antarctic Peninsula region, have been facing rates of regional climate change in recent decades that are the most rapid in the Southern Hemisphere, as well as the consequences of the anthropogenically caused stratospheric ozone hole. These provide both further challenges to the organisms native to the continent and its surrounding oceans, and a test-bed or proxy for understanding the consequences of change for organisms and ecosystems globally. Terrestrial ecosystems and biodiversity, the primary focus of this chapter, are generally depauperate, primarily comprised of cryptic and microscopic groups that are often overlooked except by specialists. Antarctic marine ecosystems, in contrast and despite also facing extreme seasonality and chronic exposure to near-freezing temperatures, can be highly diverse and comprise considerable biomass, possibly second only to tropical coral reefs.

General Overviews

Walton 2013 introduces the history and development of scientific research in Antarctica. An overview and introduction to the physical characteristics and biodiversity of the three widely recognized biogeographic regions of Antarctica (sub-, maritime, and continental Antarctic) is given by Convey 2017. Of these regions, the most biodiverse is the sub-Antarctic, with more individual detail on its component islands given in the synthesis journal special issue Selkirk, et al. 2007. The seminal two volumes of Laws 1984 provide thorough and still relevant source descriptions of Antarctic ecology and environments, both marine and terrestrial, as does Friedmann 1993 for terrestrial microbial ecosystems. The journal special issues Rogers, et al. 2007 provides a more recent synthesis, placing Antarctic studies in the wider integrated context of “genes to ecosystems.” Thomas, et al. 2008 and Beyer and Bölter 2002 provide integrated syntheses of physical and biological aspects of terrestrial ecosystems, the former being a bipolar volume with a wider remit than Antarctica alone. Chown, et al. 2015 provides a detailed review of Antarctic biodiversity elements, including discussion of contemporary trends of change. The physical and biological processes and consequences of climate change—past, present, and future—in Antarctica are documented by Turner, et al. 2009, with Bergstrom, et al. 2006 providing a more detailed compendium of studies of biological consequences.

• Bergstrom, D., P. Convey, and A. H. L. Huiskes, eds. 2006. Trends in Antarctic terrestrial and Limnetic ecosystems. Dordrecht, The Netherlands: Springer.

  Edited book volume integrating studies of different forms of change and biological consequences across Antarctica and the sub-Antarctic.

• Beyer, L., and M. Bölter. 2002. Geoecology of Antarctic ice free coastal landscapes. Berlin: Springer.

  DOI: 10.1007/978-3-642-56318-8

  Volume linking the physical terrestrial environment in Antarctica (soils, rocks) and its associated biology and ecology.

• Chown, S. L., A. Clarke, C. I. Fraser, S. C. Cary, K. L. Moon, and M. A. McGeoch. 2015. The changing form of Antarctic biodiversity. Nature 522:431–438.

  DOI: 10.1038/nature14505

  Up-to-date review of patterns and composition of biodiversity in marine and terrestrial ecosystems, and contemporary challenges to that diversity.

• Convey, P. 2017. Antarctic biodiversity: Reference module in life sciences. Edited by Bernard D. Roitberg. Amsterdam: Elsevier.

  Overview of Antarctic biogeography and diversity.

• Friedmann, E. I. 1993. Antarctic microbiology. New York: Wiley.

  Overview of Antarctic microbiology and microbial ecosystems, the dominant terrestrial ecosystems of Antarctica.

• Laws, R. M., ed. 1984. Antarctic ecology. London: Academic Press.

  Seminal and still relevant volumes introducing physical and biological aspects of Antarctic ecosystems.

• Rogers, A. D., E. J. Murphy, A. Clarke, and N. M. Johnston, eds. 2007. Special issue: Antarctic ecology: From genes to ecosystems, Part 1. Philosophical Transactions of the Royal Society B Biological Sciences 362:1–166.

  Journal special issues integrating studies, across multiple disciplines, of the structure and function of Antarctic organisms and ecosystems. See also Part 2 of these special issues in the same volume (pp. 2183–2378).

• Selkirk, P. M., P. G. Quilty, and M. Davies, eds. 2007. Special issue: The sub-Antarctic. Papers and Proceedings of the Royal Society of Tasmania 141.

  Journal special issue introducing the distinctive islands and ecosystems that make up the sub-Antarctic.

• Thomas, D. N., G. Fogg, P. Convey, et al. 2008. The biology of polar habitats. Oxford: Oxford Univ. Press.

  DOI: 10.1093/acprof:oso/9780199298112.001.0001

  Very accessible textbook introducing polar ecosystems, north and south.

• Turner, J., R. Bindschadler, P. Convey, et al., eds. 2009. Antarctic climate change and the environment. Cambridge, UK: Scientific Committee on Antarctic Research.

  A major report coordinated by the Scientific Committee on Antarctic Research, extensively documenting physical and biological aspects of change research across the Antarctic, divided into main sections addressing past, present, and future (predicted) change.

• Walton, D. W. H. 2013. Antarctica: Global science from a frozen continent. Cambridge, UK: Cambridge Univ. Press.

  DOI: 10.1017/CBO9780511782299

  Overview of the history and development of globally relevant science in Antarctica.