Climate Change
Over the past years most individuals have become acutely aware that
the
intensity of human and economic development enjoyed over the 20th century
cannot
be sustained. Material consumption and ever increasing populations are
already
stressing the earth’s ecosystems. How much more the earth can take
remains a
very heated issue. Here a look at the facts sheds some very dark
light. In 1950,
there were 2.5 billion people, while today there are 5.8
billion. There may well
be 10 billion people on earth before the middle of
the next century. Even more
significant, on an ecological level, is the rise
in per capita energy and
material consumption which, in the last 40 years,
has soared faster than the
human population. "An irresistible economy seems
to be on a collision course
with an immovable ecosphere." Based on these
facts alone, there is grave
reason for concern. Taken further, it is even
more frightening to note that,
while man has affected the environment
throughout his stay on earth, the impact
has been most intense in the
relatively short industrial era. Since the
industrial revolution, and over
the past century in particular, man’s
ecological footprint on the earth has
quickly grown from that of a child to one
of a giant. True, this period is
heralded as an economic success story, which it
certainly has been. However,
many argue that it seems increasingly likely that
the path to man’s success
will soon slope downward to his demise. The climate
is changing, and so must
we. This paper will look at the coin of climate change,
where on the one side
the human impact on the earth will be shown, and on the
other, the impact of
earth on man. Such a study is inevitably somewhat
polemical, as it is still
open to debate what the precise effects of man have
and will be on climate
change, and also what climate change will mean to man. It
will also be quite
general in analysis, as a paper of this scope can allow no
more. What will be
made clear, nevertheless, is that the relationship between
man and earth is
clearly changing. More specifically, man is outgrowing the
earth. If the
relationship is to continue—indeed prosper—then a new balance
needs to be
found. The issue of climate change holds one important key to this
balance.
Man and the Environment Thomas Malthus is well remembered for his
position as
a doomsayer. When looking at the rates of population growth in
Victorian
England, he saw unchecked growth as leading to a rapid decline in the
living
standards of man. He blamed this decline on three main factors:
the
overproduction of offspring; the inability of natural resources to
sustain
rising human population; and the irresponsibility of the lower
classes to
prevent their overpopulation. Very generally, Malthus suggested
that this trend
could be controlled only if the family size of the lower
classes was regulated
so that poor families would not produce more children
than they could support.
He predicted that the demand for food would
inevitably become far greater than
the available supply of it. This
prediction was rooted in the thought that
population, when unchecked,
increased geometrically; i.e., 2,4,8,16,32... while
food products, or as he
called it ‘subsistence’, only grew at an arithmetic
rate; i.e,
1,2,3,4,5,...... He provided only a basic economic reason for this
however,
and generally attributed famine, poverty and other catastrophic
occurrences
to divine intervention (he was a very religious man, a clergyman, in
fact).
He believed that such natural outcomes were essentially God’s way
of
preventing man from being lazy. The point here is not to provide an
evaluation
of Malthus, and one might well argue that he was wrong in many of
his
predictions; but rather to highlight the posit that man has long been
living
beyond his means. Sooner or later, this will have its consequences. As
a
species, our success has certainly been impressive, but it has come by
turning a
blind-eye to our surroundings. "A prime reason for our success is
our
flexibility as a switcher predator and scavenger. We are consummately
adaptable,
able to switch form one resource base—grasslands, forests or
estuaries—to
another, as each is exploited to its maximum tolerance or use
up. Like other
successful species we have learned to adapt ourselves to new
environments. But,
unlike other animals, we made a jump from being successful
to being a runaway
success. We have made this jump because of our ability to
adapt environments for
our own uses in ways that no other animal can match."
Whether or not man can
continue to adapt to the emerging environment,
however, is a difficult question.
In a (literally) rapidly changing
world, it is difficult to look back on past or
present to divine the future.
But, using Malthus’ line of reasoning, one way
or another mother nature will
surely ‘take care of us’. "Lack of
resources, environmental degradation,
famine and disease will in the painful
fashion known by our ancestors cut our
species back. AIDS is the obvious example
of a way in which to do
it....Conditions already exist in several African
countries for the virus to
kill more people than are being born...However, with
its incubation period of
as much as ten years or even more, AIDS is not a
boom-and-bust infection like
the Black Death. Unchecked it could move on a
time-scale of 200 rather than
20 years. But the effects could be as
devastating." It is thus clear that we
can not go on as we have in the past.
The questions of ‘when’ and ‘how’
environmental degradation will catch
up with us remain. In passing, it should
be noted that there are several (weak)
arguments to be made suggesting the
patterns of climatic change that have, and
will still, occur to be quite
beyond the understanding and influence of mortal
men. As argued by C. W.
Thornthwaite in 1956, "man is incapable of making any
significant change in
the climatic pattern on the earth; that the changes in
microclimate for which
he is responsible are so local and some so trivial that
special instruments
are often required to detect them." Another interesting
argument against the
severity of global warming, forwarded by Meyer in 1996, is
the "artefact of a
transition of stationing weather observatories near cities
that have grown
considerably during the same period. And place this curve, with
its
relatively small fluctuations, net to one of natural temperature changes
over
the last 20,000 years, and one might well despair of hearing any
human
impacts against so noisy a background." These arguments bring to light
the
controversy that surrounds the urgency of global warming and climatic
change.
Indeed, standing alone they do make compelling assertions that
can only be
countered by the application of theory. As also noted by Meyer,
"only by
adding a theoretical explanation of the workings of the climate
system, the
processes that generate the events that we experience as weather
and the order
that we discern as climate, can we suggest with some confidence
what would have
been or would be the consequences of particular human
activities." The
Importance of Environmental Viability Before moving on,
it is necessary to
highlight the importance of environmental viability. While
this may already be
well known, it is equally apparent that most individuals
do not perceive it as
an immediate problem. For most, concern with the
environment is a distant
long-term problem that does not require today’s
attention. This has much to do
with the lifestyle that has created the
problems in the first place. In our
increasingly interlinked world there is a
common strive towards a ‘global’
economy which is characterised by the
swelling of liberalised trade and
financial capital flows. Though it is not
certain at this point where this will
lead, it is very likely that the result
will be increased economic activity and,
in turn, increased material and
resource consumption. For many, at least in the
developed world, this means
increased prosperity and enhanced standards of
living. The glamour of this
lifestyle, however, tends to hide the ugly facts.
Consider, for instance,
that already at this stage of development, "rates of
resource harvesting and
waste generation deplete nature faster than it can
regenerate....As the world
becomes ecologically overloaded, conventional
economic development actually
becomes self-destructive and impoverishing. Many
scholars believe that
continuing on this historical path might even put our very
survival at risk."
In contrast to the impressions of many, the environment is
an immediate
problem. Though environmental concerns are widespread and many,
perhaps the
most challenging is the significant (30%) increase in greenhouse
gasses
accumulated in the atmosphere since the industrial revolution. At
present
rates of increase, these greenhouse gasses will again double by the
turn of the
next century. The effects this will have on the earth’s climate
remain
controversial, but most agree that the earth’s equilibrium temperature
will be
affected. The argument here remains, how much? This question will be
looked at
in the forthcoming section. Climatic Change It is not surprising to
note at this
stage that "fluctuations and changes in climate occur both
spatially and
temporally, the causes of which are a source of much
speculation and
controversy. What is unequivocal is that the past 2 to 3*106
years (and more)
have been characterised more by change than by constancy. It
is equally apparent
that climatic change, whether it is a response to natural
or cultural stimuli,
is complex. It is not yet understood which factors,
either singly or in
combination, create positive feedback, nor is it
understood how they
interact." Even further, the indices of climatic and
environmental change over
the past 2 to 3*106 years have been proxy records,
which makes the
identification of their underlying causes a formidable task.
Having noted these
inherent problems, its is possible to objectively evaluate
some of the
predictions that have been forwarded over time. There are several
ways by which
climatic change can be recorded and understood. Three of the
most well known are
quaternary subdivisions based on the terrestrial record,
ocean sediment cores,
and ice cores. These methods have been used in
isolation and also in conjunction
with one another. Of particular interest
here is the growing body of data that
has been collected from ice cores that
is contributing to studies of
environmental change and aiding correlations
between polar, continental and
ocean sediment records. "The polar ice sheets
and those of high tropical
mountains are nourished by precipitation from the
atmosphere, the composition of
which is thus recorded as successive layers of
ice accumulate. Such records
provide information on environmental change over
the past ca. 200K years and
base line data from pre-and post-industrial
levels for the biogeochemical
cycling of metals such as lead." Over the past
century, countless theories
about climate change have been advanced and
tested using the above techniques.
First to be highlighted are those that
look at climatic change as part of a
system of internal adjustments within
the climatic system. "Several have
emphasised changes in the quantity and
quality of solar radiation, especially in
relation to sunspot
cycles...Currie’s (1995) identification of the 18.6 year
lunisolar cycle and
the 11 year solar cycles in Chinese dryness/wetness indices,
for example."
Such phenomena have been associated with floods, draughts, poor
harvests, and
the like. A 1988 study by Labitzke and Loon made a connection
between sunspot
maxima/minima and quasi-biennial oscillation (QBO). "The QBO
is an
oscillation of the zonal wind component in the stratosphere above
the
equatorial region with a periodicity of ca. 27 months." Their study over
a 36
year period pointed out a positive link between "warmer winters during
the
Sun’s more active periods and between colder winters when the Sun is
least
active and when the QBO is in a westerly direction." They found that
the
reverse conditions also applied. While this relationship has subsequently
been
criticised and generally disrespected, recent polar ice core samples
have indeed
shown correlations consistent with the study. Indeed, a 1990
study by Beer et al
linked "10Be deposition with the 11 year sunspot in Dye 3
ice core from
Greenland. Beer et al. state that increased levels of 10Be
occur when solar
activity declines; and because the intensity of the solar
wind is reduced there
is an increase in the generation of cosmogenic isotopes
such as 10Be and 14C."
Another 1990 study by Wigley and Kelly not only
fortifies but also adds to these
findings. "Not only is there a relationship,
albeit complicated by the effects
of precipitation, between the 10Be in the
Vostok ice core and temperature
change, but there is also a possible
relationship between the 14C concentrations
and fluctuations in glaciers. The
nature of this relationship and the way it
varies have yet to be determined;
for now, change in solar irradiance, alias
sunspots cycles, remain as
enigmatic as ever." Tree ring data has also been
helpful in the study of
natural climatic change. In addition to the variables
just noted, there are
researchers who believe that the quantity and quality of
solar radiation that
reaches the earth is mainly affected by dust and sulphate
aerosols, usually
concomitant to volcanic eruption. "The dust scatters and
partially reflects
incoming solar radiation whereas the aerosols act as
cloud-condensation
nuclei. Both cause reduced temperatures for short-lived
periods unless the
volcanic eruptions are very large." Tree ring evidence has
found that cool
summers since the 17th century have indeed been primarily due to
volcanic
eruptions. Volcanic eruptions can further influence climate by
their
pollution of the oceans. "some of the dust will settle into the water
body,
providing nutrients such as iron and other cations, which may stimulate
primary
productivity in maine phytoplankton. Their uptake of carbon dioxide
could reduce
its concentration in the atmosphere and contribute to global
cooling by
diminishing the greenhouse effect." There can be little doubt that
the
combination of these, and various other factors, does induce a varying
degree of
cyclical climatic change. However, some suggest that none of them
contribute
sufficiently to create positive feedback that would effect changes
in the
magnitude of glacial-interglacial swing. "It is now widely accepted
that
astronomical forcing, the Milankovitch theory, is the most important
primary
cause of Quaternary glacial-interglacial cycles and probably those of
earlier
geological periods....It is the change in the orbital eccentricity
that is
thought to drive the glacial interglacial cycle. These cycles
influence the
amount of solar radiation received at the Earth’s surface,
especially in the
high latitudes of the northern hemisphere." However, these
cycles have proven
to have little effect on insolation. Other non-naturally
occurring factors are
therefore responsible for the climatic changes
anticipated. Popular causes are
the greenhouse gases, notably carbon dioxide
and methane, whose changes in
atmospheric concentration parallel global
warming and cooling. Further, there
may also be a relationship between "ocean
circulation, atmospheric
concentrations of greenhouse gases and global
temperature change. The production
and dampening of North Atlantic Deep Water
in particular is considered to be a
mechanism whereby temperature change over
the Arctic ice cap is translated into
global change." Whatever the particular
cause of climatic change, what
interests many observers is how the changes
will impact on human existence. It
is reasonably safe to say that, in
aggregate, the changes will be large and
profound. Indeed, it is quite
possible that human life and ecosystems in some
parts of the world will not
be able to survive. In all likelihood, the change is
probably going to be a
reasonably quick one, occurring perhaps within decades,
and most certainly
within a century. "Across the globe, changes in temperature
would be
reflected, in complex ways, in the migration of rainfall patterns,
with
enhancement in some areas and drying in others. Short-term weather
events might
become more variable and severe and unusual storms occur more
frequently.
Forests, sensitive to temperature, might be severely damaged
if the rate of
warming exceeded the rate at which the forest species could
migrate toward more
suitable conditions, and such migration would be widely
obstructed where other
land uses stood in the way." Moreover likely is that
the melting of the polar
ice caps would cause the sea level to rise. While
some credible arguments
actually suggest that the sea level would decrease
(due to increased
precipitation in the polar regions), the mainstream logic
does rather suggest a
rise to the tune of several centimetres per decade. In
time, this would surely
flood very low-lying coastal areas, and increase
erosion and stress on
shorelines around the world. This knowledge, however,
is of little comfort or
interest to most people. The only fact that can
perhaps involve people and ease
their tensions is knowing which particular
locations will be affected, and how
they can begin to prepare themselves. It
is towards this difficult question that
the following question turns.
Regional and Local Effects of Climate Change
Making any specific or even
generalised claims about regional and local climate
changes is even more
controversial than the effects of climate change at large.
"Existing
lakes and inland seas do have some measurable effects on temperature
and
humidity in the ribbon of land along their shores, but no so large and
so
widespread as ordinarily to justify creating new ones as climatic
generators."
The same type of controversy surrounds the desertification
of land. Looking to
the cases of the desertification of the middle east,
northern Africa, and India,
it is argued that "overgrazing by livestock both
raised the albedo of the
surface and injected dust into the air; thus
altering the regional heat balance
by reflecting away more solar radiation. A
net cooling from these processes then
promoted atmospheric stability and
suppressed rainfall; the vegetation withered
under the lessened rainfall and
more dust swirled upward, magnifying the
original impact." The example of the
diminishing rainforests provides another
good, though controversial, case. As
has been witnessed in these regions to some
degree, changing the earth’s
physical landscape can have affects on
microclimates. Cities, too, have
witnessed some significant climatic changes as
a result of increased
urbanisation. The well-known ‘heat island’ effect;
i.e., a net elevation of
temperatures above those found in the adjacent
countryside, has been well
documented. "It stems particularly from changes in
the land surface and the
energy budget. Cities themselves generate much of the
heat in which they bask
or swelter. The roughness of the urban land surface
retards the speed of the
winds, and thus lessens the dispersion of heat; the
impermeable and
well-drained surface is less moist, and so less heat is lost
through
evaporation; and the structures and surfaces typical of the city absorb
and
retain heat at high rates." This increased heat may in turn result in
fog,
storms, precipitation induced by convective heating and pollution
condensation.
On a larger regional level, the distribution of species
will be affected by
climatic change, which is likely to have widespread
consequences for human life.
Agricultural pests will be displaced, and
the incidence of ‘disease vectors’
through the spread of malaria carrying
mosquitoes, for instance, will affect the
health and well-being of human
populations. Mannion makes the observation that"areas of high altitude are those
which have been most directly affected by
the advance and retreat of glaciers
and ice caps. Indeed, the Arctic and
Antarctic zones are currently
experiencing glaciation, and it is from these
areas that much can be learned
about glaciation." Many others share this posit
that higher altitude will be
more affected, but how much more remains the
question. In sum, it must be
said that "the diversity of the earth’s surface
translates into a diversity
of physical impacts of global changes, different
social impacts even of
similar physical ones, different expectations of their
impacts—which , of
course, have often been wide of the mark—and different
costs that any
globally uniform change in behaviour would incur." Based on
this observation,
it is quite likely that landlocked countries have nothing to
fear in terms of
rising sea levels, and areas that have traditionally
experienced poor levels
of rainfall may actually benefit from increased
precipitation. Canada,
however, as a nation that is very dependent on
agriculture, forestry, and
fisheries—and thus more dependent on climatic
conditions—will likely be quite
vulnerable to any climatic shifts. In general,
however, it can be said that
"climate change may create opportunities for gain
as well as for loss, but
countries with different endowments of skills and
capital will differ in
their ability to exploit those opportunities."
Conclusion As has been
advanced throughout this paper, there is a considerable
degree of uncertainty
surrounding the climatic future of the earth. This,
according to Mannion,
"highlights the complexity of the climate system and the
inadequacy of
current scientific understanding." This vein of thought also ran
through the
Rio Earth Summit, which recognised the reality of global warming,
but also
the substantial scientific uncertainty with regard to its timing
and
magnitude. This lingering confusion has made the problem of global
environmental
change "the largest single problem facing the world scientific
community."
But, while the precise impact of man’s footprint on the earth
cannot be
measured with great accuracy, there is no reasonable man who will
argue that
current rates of consumption are either beneficial or wholly
necessary. Indeed,
it is quite intuitive to conclude that increasing
industrialisation and
increased economic output is a step in the wrong
direction, at least in terms of
the environment’s wellbeing. Given the state
of present day research, it has
reasonably been estimated that "under a
business as usual scenario of
continued growth of fossil fuel use, and hence
of greenhouse gas emissions, the
global average temperature is estimated to
rise at a rate close to 0.3C per
decade—a rate which is probably greater than
any that has occurred on earth
since the end of the last ice age, some 10,000
years ago. Associated with the
rise in global average temperature will be
substantial changes in regional
climate, especially in the intensity and
frequency of droughts and floods."
Though impossible to prove, in
aggregate it has been argued that the change will
be large and greater than
the earth has seen since the last ice age. If this is
even close to the
truth, it is very likely that human beings and the earth’s
ecosystems will
not be able to sustain the pace of change in their present
surroundings. What
will happen at the regional and local level, however, is much
more difficult
to predict though in some cases, will likely be even more
devastating. From
what has been shown in this paper, there is distinct reason to
suspect that
higher latitudes will experience greater overall warming than
lower
latitudes. If this is indeed the case, "the release of vast stores of
carbon
from the tundra peatlands and boreal zone will reinforce global
warming.
Moreover, if there are further reductions in acidic emissions,
which at current
levels cause a counteracting effect, global warming will be
accelerated." Put
simply, this is not a good thing. Quantifying the extent of
the potential damage
is not only beyond the scope of this paper, but perhaps
beyond human
comprehension (at this point) and even worse, missing the point.
The only
certainty about future climatic change is indeed uncertainty of its
extent. It
might not be wrong, given such circumstances, to prepare for the
worst. The
picture that this study has painted is, quite apparently,
confusing and sombre.
However, there is a faint stroke of optimism that
can be added. E. G. Nisbet
notes that "despite our losses, we are
intellectually and physically richer
than any other generation of humanity.
Our poverty is spiritual. It is well
within our power to be optimists, if we
can dispel the cynicism of the past
decades. If we are optimists, most things
are possible. The challenge to cherish
the planet, to construct a new global
economy, is far less than the challenge,
in 1940, to defeat the last threat
against human hope." This strain of
reasoning provides a welcome contrast to
the depressing observation noted by
Barrett at the opening of this study.
And it is true, there is nothing to
suggest that we are firmly locked into a
future that is condemned. For the first
time in history, it may well be
possible for a balance to be found between man
and
nature.
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