Whether or not Global
Warming is Real – A View Point
Summary: It is not
disputed that mean temperature of Earth has increased by 0.8° C
since the early 20th century. Various
factors affecting Earth’s surface temperature have been examined and it is
found that no mathematical correlation exists between those factors and Global
Warming. It is suggested that Earth dynamically keeps its surface temperature.
The purpose of
this article is not to dispute generally accepted facts or to deny projected
effects of Global Warming. The purpose of this article is to examine whether or
not evidence that has accumulated is being correctly interpreted. Therefore
cumulative evidence is generally presumed to be correct. I have principally
relied upon Wikipedia to build up this article.
According to
Wikipedia:-
“Global
warming is the rise in the average temperature of Earth's atmosphere and
oceans since the late 19th century and its projected continuation. Since the
early 20th century, Earth's mean surface temperature has increased by
about 0.8 °C (1.4 °F), with about two-thirds of the increase
occurring since 1980. Warming of the climate system is unequivocal, and scientists are more than 90% certain that it
is primarily caused by increasing concentrations of greenhouse gases produced by
human activities such as the burning of fossil fuels and deforestation. These
findings are recognized by the national science academies of all major
industrialized nations.
Climate model projections were summarized in the 2007 Fourth Assessment
Report (AR4) by the Intergovernmental Panel on Climate Change (IPCC). They
indicated that during the 21st century the global surface temperature is likely
to rise a further 1.1 to 2.9 °C (2 to 5.2 °F) for their
lowest emissions scenario and 2.4 to
6.4 °C (4.3 to 11.5 °F) for their highest. The ranges of these
estimates arise from the use of models with differing sensitivity to
greenhouse gas concentrations.”
Wikipedia further
states:-
“Global warming
controversy
The global
warming controversy refers to a variety of disputes, significantly
more pronounced in the popular media than in the scientific
literature, regarding the nature, causes, and consequences of global
warming. The disputed issues include the causes of increased global average
air temperature, especially since the mid-20th century, whether this warming
trend is unprecedented or within normal climatic variations,
whether humankind has contributed significantly to it, and whether the
increase is wholly or partially an artifact of poor measurements. Additional
disputes concern estimates of climate sensitivity, predictions of
additional warming, and what the consequences of global warming will be.
In the scientific
literature, there is a strong consensus that global surface
temperatures have increased in recent decades and that the trend is caused
mainly by human-induced emissions of greenhouse gases. No scientific body of
national or international standing disagrees with this
view, though a few organizations hold non-committal position.
From 1990–1997 in
the United States, conservative think tanks mobilized to undermine
the legitimacy of global warming as a social problem. They challenged the
scientific evidence.”
The difficulty with
Global Warming is that cause-effect relationship between increased temperature
and the alleged causes has never been scientifically established. Only certain
associated changes have been alleged to be the cause. We are not certain if
these associated changes are indeed the culprit. Moreover even these
projections are based on empirically generated climate models. This is
presumably because we do not yet understand how Earth keeps its
climate/temperature. So literature has plenty of mutually contradictory
observations, claims and counterclaims. Plenty of positive feedback and
negative feedback cycles are known but all put together do not explain as to
how Earth keeps its climate/temperature within a range. Attempts to link
Earth’s temperature with solar constant and its variations just don’t meet the
eye. Solar constant is highest during winters and lowest during summers.
Variations in solar constant do not exceed 0.1%. Wikipedia states about Solar
Constant as under:-
“Solar output is
nearly, but not quite, constant. Variations in total solar irradiance were too
small to detect with technology available before the satellite era. Total solar
output is now measured to vary (over the last three 11-year sunspot cycles) by approximately 0.1%; see solar variation for details.
The solar constant
includes all types of solar radiation, not just the visible light. It
is measured by satellite to be roughly 1.361 kilowatts per
square meter (kW/m²) at solar minimum and approximately 0.1% greater (roughly
1.362 kW/m²) at solar maximum. The actual direct solar irradiance at
the top of the atmosphere fluctuates by about 6.9% during a year (from
1.412 kW/m² in early January to 1.321 kW/m² in early July) due to the
Earth's varying distance from the Sun, and typically by much less than 0.1%
from day to day. Thus, for the whole Earth (which has a cross section of
127,400,000 km²), the power is 1.740×1017 W, plus or minus
3.5%. The solar constant does not remain constant over long periods of time
(see Solar variation), but over a year varies much less than the variation
of direct solar irradiance at the top of the atmosphere arising from the
ellipticity of the Earth's orbit. The approximate average value
cited,1.361 kW/m², is equivalent to 1.952 calories per minute per square
centimeter, or 1.952 langleys (Ly)—or, in SI units— about 81.672
kJ/m² per minute.
The Earth receives a
total amount of radiation determined by its cross section (π·RE²),
but as it rotates this energy is distributed across the entire surface
area (4·π·RE²). Hence the average incoming solar radiation,
taking into account the angle at which the rays strike and that at any one
moment half the planet does not receive any solar radiation, is one-fourth the
solar constant (approximately 340 W/m²). At any given moment, the amount
of solar radiation received at a location on the Earth's surface depends on the
state of the atmosphere, the location's latitude, and the time of day.”
The amount of solar
energy Earth receives for sun is sufficient to increase surface temperature
beyond 100° C in less than one hour. Moreover amount of energy can’t be
correlated with observed weather conditions, being the highest in winters and
lowest in summers. Even the extent of variation in solar constant can’t be
correlated with rise of Earth’s temperature by 0.8° C during the last century.
Moreover it is self-evident that Earth was unable to dissipate energy it
receives from Sun; it would have been hot enough that no known life forms
except (probably) some kind of Extremophiles could have survived. Even
depletion of Ozone layer does not correlate with Global Warming.
In 2008, total
worldwide energy consumption was 474 exajoules (474×1018 J=132,000
TWh). This is equivalent to an average power use of 15 terawatts (1.504×1013 W).
This is 0.009% of the amount of energy Earth receives from Sun during any year.
Therefore increased energy consumption due to increased human activity can’t
account for increase in mean temperature of Earth from 13.9° C to 14.6° C
(approximate increase of 5.4%) during past 100 years.
From the above
discussion, it is evident that Earth rigorously keeps its temperature and
Earth’s temperature bears no direct correlation to amount of energy it receives
from sun or released by burning of fuels to meet demands created by increased
human activity. Further no cause-effect relationship with accumulation of so
called green house gases and Earth’s temperature has been established.
Increased concentration (16% to 167% since 1750) of naturally occurring
greenhouse gases does not linearly correlate with extent of reported mean
temperature change. Same is the case with increased positive radiative forcing.
Increased positive radiative forcing for different naturally occurring
greenhouse gases has increased from 0.18 W/square meter to 1.79 W/square meter
but bears no correlation with reported temperature increase.
Therefore all that
can be said at the moment is that Earth’s surface temperature is the result of
dynamic equilibrium which is attained and maintained by a variety of mechanisms
having positive and negative feedback loops. So the reported increase in mean
temperature of Earth may not be due to alleged accumulation of green house
gases or increased human activity but may be the result of shift in dynamic
equilibrium. How this dynamic equilibrium is determined, attained and
maintained is the key issue to be resolved if we want to understand the reason
underlying reported increase in mean temperature of Earth. Empirically worked
out climate models are really not of much help because they indicate only
association of facts and not the rationale behind those facts. Scientific
resolution of problem of Global warming is not possible in the absence of
proper understanding of the phenomenon. Last but not the least, nature is
self-perpetuating and this invariably is the result of dynamic conservation of
status-quo.
Author: Dr Mahesh C. Jain is a practicing medical doctor and has
written the book “Encounter of Science with Philosophy – A synthetic view”. The
book begins with first chapter devoted to scientifically valid concept of God
and then explains cosmic phenomena right from origin of nature and universe up
to origin of life and evolution of man. The book includes several chapters
devoted to auxiliary concepts and social sciences as corollaries to the concept
of God. This is the only book which deals with origin of nature and universe
from null or Zero or nothing.
http://curatio.in
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