For the last forty
years, the world has been aware about a possible planetary climate change
induced by Carbon Dioxide emissions from fuel fossil burning. In fact, the
IPCC, a United Nation’s organization, states that they are 99% sure that the
human being is the major responsible for the rising global temperatures since
the beginning of the Industrial Revolution (Stocker et all, 2013, p 5-7). However, many people
have a different opinion about this issue. This group, that includes people
from different occupations like climatologists, physicians, and geographers,
are known as “skeptics”, since they partially or totally disagree with this
theory. Many of them states that there is no conclusive evidence about the
climate change, while others don’t agree that the rising CO2 concentration is
capable to alter the world climate. The purpose of this paper is to analyze the
skeptics’ claims about climate change in order to understand why they are so skeptical
about a well-documented and peer-revised topic like climate change. Some issues
pointed by the skeptics are improper methodology, excessive reliance on
computer models, misinterpretation of historic climatic register, and biased
science.
Is Global temperatures really rising?
The first question that comes in
mind is: what the term average global temperature
means? It is possible to have a single representative temperature for the
entire planet? That is the first point cast in doubt for many skeptics, since
this number can vary according to the adopted methodology. To obtain this
number, meteorologists and climatologists rely on temperature information
provided by hundreds of meteorological stations spread around the world. Those
stations are where the problem begins. Some critics argue that temperatures
near cities are higher than that measured in the country or in the forests.
This difference is attributed to the urban
heat island effect, a warming effect caused by buildings, cars, industry,
asphalt, reduced vegetation areas, etc., that changes the air circulation
patterns, albedo, air humidity, and several other factors, causing a difference
of temperature between city and the country that can reach 12ºC (Akasofu, 2010).
Therefore, if a meteorological station is located in an urban area, its temperature
measures are subject to the same trend.
Another
point that concerns the Skeptics is that several rural meteorological stations
have been closed in the last years. They also claim the existence of a strong
correlation between rising temperatures and the reduction of those rural
stations (D’Aleo, 2002). Therefore, the current rising temperatures would be
just a consequence of the way data is collected. Skeptics have been complaining
that temperature data in the United States is not completely available for pair
reviewing, making more difficult to verify the quality of the data involved in
climatic modeling (Global Climate Change Facts, n.d.).
Figure 1. This graphic shows the correlation between the number of meteorological stations (blue dots) and the average temperature (purple bars). The rising temperatures in 1990 coincide with the closing of several stations – most of them in rural areas - around the world (Global climate change facts, nd).
Why different models
show different results?
The
main tool used by climatologists to predict climate tendencies is computer
modeling. Those models are very useful for weather forecasts, providing
reliable three to four days’ prognostics. Nevertheless, when the same models
are used to climatic forecasts, which involves larger periods, the results diverge
among them. The model forecasts also diverge from observed stable temperature
trend in the last years, so the skeptics state that the models are unable to
provide accurate climatic forecasts.
Figure
2. An interpretation of changes in global average temperature from 1800 to
2012. The temperature in the vertical axis is for reference scale. An insert
above the yellow box is a detailed version of data shown in the yellow (Akasofu,
2010).
Comparing with what?
Another
point made by the skeptics is that all models compare current temperatures with
the period between 1860 and 1920. However, 1860 is considered the end of a
period called “the little ice age”. According to Akasofu (2010), the Earth is
still recovering from this cold period, one of the coolest in the last 8000
years, while the computer models use to predict global temperature trend rely
only in a short period beginning in the 1970s. This choice of data and its
linearization suggests a more accelerated warming trend than that we can get
from the linearization of the entire period since 1860, as we can observe in
figure 2. Nowadays, we are in the cooling period of the Pacific Multi-decadal
Oscillation, which enhance the difference between measured temperatures and
computer models results. Therefore, any observed warming trend is probably part
of this recovering process, instead of an effect of the anthropogenic
activities.
Who benefits from global warming?
Global
warming is a biased topic, not only academically speaking yet also economically
and politically. Some skeptics see a hidden agenda behind “global warmers” –
people that advocate the global warming - position. Assumed skeptical
researchers face difficulties in obtaining research funds, and the media have
been giving more space to warmers than to skeptics. Warmers usually accuse
skeptics of being financed by the oil industry, while skeptics state that
warmers work against the developing countries, since the restrictions of fossil
fuel could jeopardize its development. Companies that make money from carbon
credit earn billions of dollars by implementing “mitigation actions”(Global
Climate Change Facts, n.d.). Surprisingly, most of those action are not
focused on reducing fossil fuel consumption or planting trees yet on building
preposterous CO2 absorbing machines, “cultivating” algae by launching iron
oxide in the ocean, trading questionable carbon credits, or even launching
orbital mirrors in order to reduce sun’s incidence. Those questionable
strategies are amazingly expensive and can be a heavy burden to the taxpayers.
The Occam's Razor
As we could see,
bad data quality, confuse methodology, improper computer models interpretation,
improper climatic history interpretation, and biasing are widespread in climate
change theory and among its defenders. This questionable scientific behavior may
be causing us to miss something important. Our incapacity of properly
understand what is really happening with the global climate can put all
humanity in danger. What if the climate is cooling instead of warming? Will we
be prepared? What if while trying to prevent a catastrophic global warming we are
causing a catastrophic global cooling? In order to really understand our
planet, science must be skeptic and unbiased. The search for elegant scientific
models, the pressure over researchers to produce scientific papers, and the
tendency of provide grants only to researchers that get economic results are
probably in the kernel of the current bias.
According to the
William of Occam’s Principle of Parsimony,
if you have two explanations to the same phenomenon, choose the simple one.
There are several natural processes that can be used to explain the current
climatic trend. Natural forcings, like the 11-year solar cycle, El Niño and the
Pacific Multi-decadal Oscillation, may be the major cause of the observed
climatic variation (Akasofu, 2010). In this case, scientists should use the Occam's
razor principle instead of looking for complex, elegant, imprecise, and
inconclusive computer models. The world climate is extremely complex, and
blaming a single aspect like atmospheric CO2 concentration is not scientific,
state the skeptics.
References:
Global climate
change facts: The truth, the consensus, and the skeptics. (n.d.). Retrieved from http://www.climatechangefacts.info
Akasofu, S. (2010). On
the recovery from the little ice age. Retrieved from http://www.iarc.uaf.edu/en/node/3811
D'Aleo, J. (2002). Is
this record warm winter a sure sign of global warming? Informally published
manuscript. Retrieved from http://www.uoguelph.ca/~rmckitri/research/intellicast.essay.pdf
Stocker, T.F., D. Qin, G.-K. Plattner,
M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley
(eds.). Intergovernmental Panel on Climate Change, (2013). Climate change
2013: The Physical Science Basis. Contribution of Working Group I to the Fifth
Assessment Report of the Intergovernmental Panel on Climate Change.
Retrieved from: http://www.climatechange2013.org/images/report/WG1AR5_ALL_FINAL.pdf
Reconsidered II:
Physical Science. Chicago, IL: The Heartland Institute.
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