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Title: BIOSPHERIC HEALTH AND INTEGRITY:


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 2C above pre-industrial levels, but
    no agreement has been reached among the worlds
    nations to prevent this increase from happening.
  • Even worse, scientists indicate that the global
    average temperature could rise by 4C as early as
    2060.1
  • A temperature of even less than 2C 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 Earths 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 Earths 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 Earths 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 worlds 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 worlds
    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
    Earths 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 arent we doing something?
  • Can it be that we dont 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.biospher
e 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.
1061704-1709 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.stockholmresil
ience.org/download/18.1fe8f33123572b59ab800012568/
pb_longversion_170909.pdf. 8Lynas, M. 2008. Six
Degrees. National Geographic, Washington, D.C.
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