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Preserving Biospheric Health: A Global Priority for Humankind

This article discusses the urgent need to prioritize the health and integrity of the biosphere, highlighting the potential consequences of neglecting its preservation. The author emphasizes the importance of monitoring and taking precautionary steps to prevent irreversible tipping points.

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Preserving Biospheric Health: A Global Priority for Humankind

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  1. BIOSPHERIC HEALTH AND INTEGRITY: THE TOP PRIORITY FOR HUMANKIND John Cairns, Jr. University Distinguished Professor of Environmental Biology Emeritus Department of Biological Sciences Virginia Polytechnic Institute and State University Blacksburg, Virginia 24061, U.S.A. November 2009

  2. Global climate change is proceeding much more rapidly than expected. • Intentions have been voiced about limiting global heating to 2°C above pre-industrial levels, but no agreement has been reached among the world’s nations to prevent this increase from happening. • Even worse, scientists indicate that the global average temperature could rise by 4°C as early as 2060.1 • A temperature of even less than 2°C is currently melting glaciers and having deleterious effects upon agricultural productivity and the biosphere. • The biosphere2 (living organisms together with their environment), which serves as Earth’s life support system and is the source of resources for the human economy, has lost biodiversity and habitat.

  3. The present biosphere is not like the ones that preceded it since the biota and climate are different. • The present biosphere has supported the genus Homo for at least 3 million years and the species Homo sapiens, to which humans belong, for 160,000-200,000 years. • Each of the five great extinctions was followed by a different biota that evolved from the survivors of the extinctions. • Humans probably could not have survived in the environment produced by the preceding biospheres, nor is human civilization likely to survive the next biosphere if “business as usual” continues. • Humankind should be nurturing the present biosphere, not only because humankind is a part of the biosphere but also because the human species evolved under the conditions the biosphere produced.

  4. The biosphere is an envelope surrounding Earth, an envelope so thin that its edge cannot be seen from outer space. • The biosphere is a mosaic of ecosystems that cover the entire Earth. The oceanic component covers about 70% of Earth’s surface and has already been affected adversely by acidification from carbon dioxide, a greenhouse gas. • The oceanic ecosystem may have already passed a major ecological/global tipping point; however, because the oceans are on “evolutionary time” rather than “human time,” a few more years may be needed to produce evidence that a major tipping point has been passed. • The global financial tipping point of 2008 was a big surprise, although 20/20 hindsight has revealed a few warning signals. • Since tipping points are essentially irreversible,3 humankind can either take precautionary steps to avoid tipping points or try to adapt when they occur.

  5. All life on Earth, including humankind, depends upon the biospheric life support system that provides both natural capital (resources) and ecosystem services. • Hawken et al.4 list four types of capital that the human economy needs for functioning properly. • (1) human capital – labor, intelligence, culture, and organization, • (2) financial capital – cash, investments, and monetary instruments, • (3) manufactured capital – infrastructure, machines, tools, and factories, • (4) natural capital – resources, living organisms, and ecosystem services. • Since both humans and natural capital are part of the biosphere, the human artifacts (i.e., financial capital and manufactured capital) are derived from the biosphere.

  6. Why then is the human economy, which is clearly a subset of the biosphere (i.e., the environment), given the highest priority by both politicians and the general public? • The present biosphere has been around for all of human history and has never given the human species any trouble until recently when anthropogenic stresses have had deleterious effects. • Scientists have been giving increasingly urgent warnings for decades to no avail. • If the present biosphere suffers collapse, the new biosphere probably will not maintain conditions as habitable for humans as the present one.

  7. A tipping point is the critical point in an evolving situation that leads to a new and irreversible development. • When an ecological tipping point is passed, the system goes into disequilibrium and may not recover for thousands, even millions, of years at the ecological level of the biosphere. • Conditions during the transition period will probably be erratic, even chaotic, but a new complex biosphere should eventually be reached if the five past biotic extinctions are a guide. • Monitoring the health and integrity of the biosphere would probably, but not certainly, provide an early warning that a tipping point was near. • This undertaking is daunting but not impossible. Cairns5 provides an outline of the steps for monitoring the health and integrity of natural capital and ecosystem services. • The biosphere probably has multiple tipping points, as is the case for most complex, multivariate systems. • A major tipping point was reached when emissions of carbon dioxide exceeded Earth’s assimilative capacity and the gas began to accumulate in the atmosphere, causing climate change. • When a tipping point has been passed, change may come gradually in human time, but not in ecological/evolutionary time.

  8. Suddenly the world is different. • Humankind cannot return to the world it once knew. • The change is irreversible and humans must adapt to the new world. • Sea level rise is one of the consequences of climate change. • The world’s rice harvest is particularly vulnerable to rising sea level. A World Bank map of Bangladesh shows that even a 3-foot rise in sea level would cover half of the rice land in this country of 160 million people. • A 3-foot sea level rise would also inundate one-third or more of the Mekong delta, which produces half of the rice in Vietnam, the world’s number two rice exporter.

  9. Suddenly textbooks seem to be describing some other world than the one humans live in.6

  10. Where might humankind be going? • Rockstrom et al.7 list nine planetary boundaries and propose quantification for seven of them. • Climate change • Ocean acidification • Biogeochemical nitrogen cycle • Phosphorus cycle • Global freshwater use • Land system change • Loss of biological diversity • Chemical pollution (yet to be quantified) • Atmospheric aerosol loading (yet to be quantified) • The authors estimate that humanity has already transgressed three planetary boundaries: climate change, biodiversity loss, and changes to the global nitrogen cycle. • Three out of seven planetary boundary conditions have been transgressed, and climate negotiations lack urgency.

  11. How can these changes be ignored when the global system is highly interactive? • Mark Lynas’ book Six Degrees8 is based on the landmark 1.4 degrees to 5.8 degrees Celsius increases in global average temperature (GAT) of the Intergovernmental Panel on Climate Change (IPCC). The increase may be much more in some regions. . . . less in others. • Cynics might say that sub-Saharan Africans are well accustomed to drought. But the evidence suggests that the extent of drying in the three-degree world is going to be far off any scale that would permit human adaptation.8, p. 125 • On the other hand, if emissions (of carbon dioxide) go on rising as they currently are, global temperatures could shoot past three degrees as early as 2050. 8, p. 134 • 2050 is a date frequently mentioned as a target date for reducing emissions of greenhouse gases. This date is too far into the future.

  12. The sleeping climate giant: positive feedback loops. • In addition to the vast amounts of carbon stored in the remaining fossil fuels, much more carbon is stored in frozen, hydrated methane on the ocean floor and in permafrost soils, wetlands, forests, soils, and so on. • When frozen methane thaws or when permafrost thaws, carbon is released into the atmosphere and accelerates global heating. • Such positive feedback is already occurring and results in increased atmospheric methane and carbon dioxide. • Another greenhouse gas, nitrous oxide, is emitted during agricultural and industrial activities, as well as during the combustion of fossil fuels and solid waste. • Any increase in emissions would act as positive feedback and increase global heating. • The same result is true of potent fluorinated gases. • Such things as increased thawing of frozen methane or permafrost will accelerate global climate change, which would probably destabilize the present biosphere. • The positive feedback loops, if strongly activated, would probably result in uncontrollable climate changes to which humankind would have to adapt or suffer. • Extinction is unthinkable, but possible.

  13. Conclusions • Humankind is rapidly approaching the creation of an alien planet because it refuses to reduce anthropogenic greenhouse gas emissions to match Earth’s assimilative capacity for them. Only a short time is left to make an emissions/capacity match before the next biospheric tipping point or before the positive feedback loops become more active. The changes humankind needs to make in lifestyles and behaviors to sustain Earth as it is presently known are almost certainly less than those needed to adapt to a markedly changed Earth. • Why aren’t we doing something? • Can it be that we don’t realize we are part of the biosphere we are destroying?

  14. Acknowledgments: I am indebted to Darla Donald for transcribing a portion of the handwritten first draft and for editorial assistance, to Karen Cairns for transcribing a portion of the handwritten first draft and for assistance with the format, and to Valerie Sutherland for converting it to Power Point. References 1Shukman, D. 2009. Four degrees of warming “likely.” BBC News 28Sept http://news.bbc.co.uk/2/hi/8279654.stm. 2definition of biosphere from http://www.merriam-webster.com.dictionary.biosphere 3Solomon, S. G-K Plattner, R. Knutti and P. Friedlingstein. 2009. Irreversible climate change due to carbon dioxide emissions. Proceedings of the National Academy of Sciences, USA. 106:1704-1709 4Hawken, P., A. Lovins, and H. Lovins. 1999. Natural Capitalism: Creating the Next Industrial Revolution. Little, Brown and Company, New York, NY, p. 4. 5Cairns, J., Jr. 2002. Monitoring the restoration of natural capital: water and land ecosystems. Chapter 1, pp. 1-31 in Advances in Water Monitoring Research, T. Younos, ed. Water Resources Publications, LLC, Highlands Ranch, Colorado. 6Rubin, J. 2009. Why Your World is About to Get a Whole Lot Smaller. Random House, NY, p. 17. 7Rockström J. and 28 additional authors. In press. Planetary boundaries: exploring the safe operating space for humanity. Ecology and Society, p. 8, online at http://www.stockholmresilience.org/download/18.1fe8f33123572b59ab800012568/pb_longversion_170909.pdf. 8Lynas, M. 2008. Six Degrees. National Geographic, Washington, D.C.

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