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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
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.
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.
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.
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)
(2)
(3)
(4)
human capital – labor, intelligence, culture, and organization,
financial capital – cash, investments, and monetary instruments,
manufactured capital – infrastructure, machines, tools, and factories,
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.
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.
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.
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.
Suddenly textbooks seem to be
describing some other world
than the one humans live in.6
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.
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.
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.
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?
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_lo
ngversion_170909.pdf.
8Lynas, M. 2008. Six Degrees. National Geographic, Washington, D.C.