2002년 1월3일 Nature 에 실린글
PAUL J. CRUTZEN
Paul J. Crutzen is at the Max Planck Institute for Chemistry, PO Box 3060, D-55020 Mainz, Germany, and the Scripps Institution of Oceanography, University of California, San Diego, 9500 Gillman Drive, La Jolla, California 92093-7452, USA.
For the past three centuries, the effects of humans on the global environment have escalated. Because of these anthropogenic emissions of carbon dioxide, global climate may depart significantly from natural behaviour for many millennia to come. It seems appropriate to assign the term 'Anthropocene' to the present, in many ways human-dominated, geological epoch, supplementing the Holocene -the warm period of the past 10~12 millennia. The Anthropocene could be said to have started in the latter part of the eighteenth century, when analyses of air trapped in polar ice showed the beginning of growing global concentrations of carbon dioxide and methane. This date also happens to coincide with James Watt's design of the steam engine in 1784.
Mankind's growing influence on the environment was recognized as long ago as 1873, when the Italian geologist Antonio Stoppani spoke about a "new telluric force which in power and universality may be compared to the greater forces of earth," referring to the "anthropozoic era". And in 1926, V. I. Vernadsky acknowledged the increasing impact of mankind: "The direction in which the processes of evolution must proceed, namely towards increasing consciousness and thought, and forms having greater and greater influence on their surroundings." Teilhard de Chardin and Vernadsky used the term 'noösphere' - the 'world of thought' - to mark the growing role of human brain-power in shaping its own future and environment.
The rapid expansion of mankind in numbers and per capita exploitation of Earth's resources has continued apace. During the past three centuries, the human population has increased tenfold to more than 6 billion and is expected to reach 10 billion in this century. The methane-producing cattle population has risen to 1.4 billion. About 30-50% of the planet's land surface is exploited by humans. Tropical rainforests disappear at a fast pace, releasing carbon dioxide and strongly increasing species extinction. Dam building and river diversion have become commonplace. More than half of all accessible fresh water is used by mankind. Fisheries remove more than 25% of the primary production in upwelling ocean regions and 35% in the temperate continental shelf. Energy use has grown 16-fold during the twentieth century, causing 160 million tonnes of atmospheric sulphur dioxide emissions per year, more than twice the sum of its natural emissions. More nitrogen fertilizer is applied in agriculture than is fixed naturally in all terrestrial ecosystems; nitric oxide production by the burning of fossil fuel and biomass also overrides natural emissions. Fossil-fuel burning and agriculture have caused substantial increases in the concentrations of 'greenhouse' gases - carbon dioxide by 30% and methane by more than 100% - reaching their highest levels over the past 400 millennia, with more to follow.
So far, these effects have largely been caused by only 25% of the world population. The consequences are, among others, acid precipitation, photochemical 'smog' and climate warming. Hence, according to the latest estimates by the Intergovernmental Panel on Climate Change (IPCC), the Earth will warm by 1.4-5.8 °C during this century.
Many toxic substances are released into the environment, even some that are not toxic at all but nevertheless have severely damaging effects, for example the chlorofluorocarbons that caused the Antarctic 'ozone hole' (and which are now regulated). Things could have become much worse: the ozone-destroying properties of the halogens have been studied since the mid-1970s. If it had turned out that chlorine behaved chemically like bromine, the ozone hole would by then have been a global, year-round phenomenon, not just an event of the Antarctic spring. More by luck than by wisdom, this catastrophic situation did not develop.
Unless there is a global catastrophe -a meteorite impact, a world war or a pandemic- mankind will remain a major environmental force for many millennia. A daunting task lies ahead for scientists and engineers to guide society towards environmentally sustainable management during the era of the Anthropocene. This will require appropriate human behaviour at all scales, and may well involve internationally accepted, large-scale geo-engineering projects, for instance to 'optimize' climate. At this stage, however, we are still largely treading on terra incognita.
FURTHER READING
Marsh, G. P. Man and Nature (1864). (Reprinted as The Earth as Modified by Human Action (Belknap Press, Cambridge, Massachusetts, 1965)).
Crutzen, P. J. & Stoermer, E. F. IGBP Newsletter 41 (Royal Swedish Academy of Sciences, Stockholm, 2000).
Clark, W. C. & Munn, R. E. (eds) Sustainable Development of the Biosphere Ch. 1 (Cambridge Univ. Press, Cambridge, 1986).
Vernadski, V. I. The Biosphere (translated and annotated version from the original of 1926) (Springer, New York, 1998).
Turner, B. L. et al. The Earth as Transformed by Human Action (Cambridge Univ. Press, Cambridge, 1990).
Mc Neill, J. R. Something New Under the Sun: An Environmental History of the Twentieth-Century World (W. W. Norton, New York, 2000).
Houghton, J. T. et al. (eds) Climate Change 2001: The Scientific Basis (Cambridge Univ. Press, Cambridge, 2001).
Berger, A. & Loutre, M.-F. C. R. Acad. Sci. Paris 323 (IIA), 1-16 (1996).
Schellnhuber, H. J. Nature 402, C19-23 (1999). |}}
Crutzen, P. J. & Stoermer, E. F. IGBP Newsletter 41 (Royal Swedish Academy of Sciences, Stockholm, 2000).
Clark, W. C. & Munn, R. E. (eds) Sustainable Development of the Biosphere Ch. 1 (Cambridge Univ. Press, Cambridge, 1986).
Vernadski, V. I. The Biosphere (translated and annotated version from the original of 1926) (Springer, New York, 1998).
Turner, B. L. et al. The Earth as Transformed by Human Action (Cambridge Univ. Press, Cambridge, 1990).
Mc Neill, J. R. Something New Under the Sun: An Environmental History of the Twentieth-Century World (W. W. Norton, New York, 2000).
Houghton, J. T. et al. (eds) Climate Change 2001: The Scientific Basis (Cambridge Univ. Press, Cambridge, 2001).
Berger, A. & Loutre, M.-F. C. R. Acad. Sci. Paris 323 (IIA), 1-16 (1996).
Schellnhuber, H. J. Nature 402, C19-23 (1999). |}}
1784년 제임스 와트에 의해 증기기관이 발명된 이후 3세기동안 인간이 지구환경에 미치는 영향은 무시할 수 없을 정도가 되었다. 이미 이탈리아의 지질학자인 Antonio Stoppani에 의해 1873년에 의해 이러한 문제가 제기되었다
지난 3세기동안 인구는 10배가 증가해서 60억을 넘어섰고, 메탄가스를 방출하는 가축의 수는 13억에 육박한다. 지구면적의 30~50%가 인간에 의해 개발되고 있으며, 열대우림의 빠른 파괴로 인해 이산화탄소가 증가하고 멸종이 가속화되고 있다. 댐건설과 강절단(?)은 흔하게 일어나고, 지구에 있는 식수 절반이상을 인간이 사용한다. 그외에도 많은 예가 있다.
이러한 짓거리는 인류의 25%에 의해서 이루어졌으며, 산성화와 스모그현상을 발생시켰다. (이런젠장~~) 21세기이내에 지구의 온도는 1.4에서 5.8도 이상 올라갈 것으로 예측된다<By Intergovernmental Panel on Climate Change (IPCC)>.
물론 혜성의 충돌과 세계대전, 전염병등의 대참사도 존재하지만, 인류는 환경변화에 영향을 미치는 중요한 요소로 간주되어야 할것이다. 과학자그룹과 기술자 그룹은 사회를 환경친화적으로 이끌어야 하며, 이는 범세계적으로 인간행동의 변화를 요구할 것이다. --김우재