Title: BIOSPHERIC HEALTH AND INTEGRITY:
1- BIOSPHERIC HEALTH AND INTEGRITY
- THE TOP PRIORITY FOR HUMANKIND
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- John Cairns, Jr.
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- University Distinguished Professor of
Environmental Biology Emeritus - Department of Biological Sciences
- Virginia Polytechnic Institute and State
University - Blacksburg, Virginia 24061, U.S.A.
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- November 2009
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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.
9Suddenly 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?
14Acknowledgments 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.