Geology Reference
In-Depth Information
EXERCISE
1
8
Global Change and Sustainability
INTRODUCTION
"The public in the industrialized nations, particularly in
the United States, must be made more aware of the
pervasive trends in environmental degradation and
resource depletion, and of the need to modify pat-
terns of life to cope with these trends."
doubters are funded by special interest groups and
fossil fuel coalitions that do not want research on, or
evidence of, global change that could impact their
economic condition (Gelbspan,
1997).
Island nations,
environmentalists, active geoscientists, environmen-
tal economists, and insurance organizations were
among the first to recognize that global change is
occurring. Now many groups are working on adapta-
tions to change and on ways to reduce human
impact globally.
We should be able to adapt to the limits of our
habitat on Earth without overshooting them. Many
organisms undergo increases and collapses in their
populations but they do not have our technology,
information, and understanding. We have models,
examples, and explanations of why societies collapse
(Diamond, 2005). We probably will never understand
how the total Earth system works; however, we need
to write the "Operating Manual for Spaceship Earth."
The final activity in this exercise is constructing a
scenario—your description of the future viewed from
50 years in the future. This forecasting approach is
used by think tanks to understand possible futures
(Schwartz,
1991).
— K
AULA AND
A
NDERSON,
P
LANET
E
ARTH
C
OMMITTEE,
A
MERICAN
G
EOPHYSICAL
U
NION,
1991
"The time to consider the policy dimensions of cli-
mate change is not when the link between green-
house gases and climate change is conclusively
proven ... but when the possibility cannot be dis-
counted and is taken seriously by the society of
which we are part. We in BP have reached that
point."
—J
OHN
B
ROWNE,
G
ROUP
C
HIEF
E
XECUTIVE,
BP A
MERICA,
1997
The quotations above capture the concern of many
geologists who understand Earth history and
change in the Earth system. In the distant past
humans did not play a role in these changes. Now
we do. In this exercise we look at changes in cli-
mate using ice cores and glacier retreat, changes in
the atmosphere through ozone and C0
2
/
and the
human component of change through population
increase and the response to projected temperature
change.
Other components of global environmental
change include deforestation and habitat loss, loss of
biodiversity (which may be the most important one),
desertification, soil erosion and agriculture, spread of
infectious disease by microorganisms, rising sea
level, modifications in weather patterns and stormi-
ness, and decreasing water resources.
A
very few scientists do not accept the evidence
of warming, or if they do, its relation to human activity.
These few doubters receive "equal time in the press"
with those actively working on the science of global
change. It has been revealed that many of the
PART A. ICE-CORE PALEOTEMPERATURES
AND GLACIER RETREAT
Ice cores provide excellent records of past atmospheric
conditions, including temperatures and CO2 concentra-
tions. Interpreting cores from ice caps in mid-latitude and
equatorial regions has been the research focus of Lonnie
and Ellen Thompson's Ice Core Paleoclimatology
Research Group at the Byrd Polar Research Center, The
Ohio State University. Material in this part of the exer-
cise has been provided by the Thompson team. Images
of the Quelccaya Ice Cap are available at
http://bprc
268
