Global Warming Geography Essay

8/13/2019 Global Warming Geography Essay

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Why Is Global Warming a Controversial Topic?

Abstract:

Global Warming is a hugely controversial issue of the 21st century, this is a result of scientific

and media speculation over the topic. The many sources of data and evidence available are

subject to a diverse variety of interpretations. These interpretations can be influenced by political agenda, as well as misreading of scientifically obtained data. The culmination of speculative

factors and poor scientific method have made ‘Global Warming’ an uncertain, and thus more

controversial topic of debate.

Introduction

It is important to separate Global warming from Climate change. Global warming

characterises the increase in greenhouse gases in the earth’s atmosphere; particularly when

attributed to human activity. The Greenhouse effect is a naturally occurring layer of gases,

including water vapour, carbon dioxide, ozone, methane, and nitrous oxide; which trap radiated energy, and therefore heat from the sun. Climate change defines any permutations in weather on

all scales, not simply variations in temperature. Climate change includes all possible factors as

culpable in the weather change. The issue of Global warming raises disparate hypothesis on

Earth’s ecological and economic future. The political element to the controversy is attributable to

a desire to persuade the present and future electorates that aspiring governments can assess

the uncertainty and create solutions to the perceived problems.

The media is responsible for generating an over dramatic and wholly unscientific

approach to climate change. Scientific papers of study and analysis can, have been distorted to

alter the emphasis of research papers, in order to make the uncertainties prevalent. This encourages a great deal of interest in any story relating to Global Warming. The process

whereby scientific sources are edited and simplified by a university press office for the

consumption of journalists, and thusly further simplification for the general public allows for a

restriction to many facets of interpretation of collected data. It is therefore reasonable to suggest

that unreliable sources contribute to the controversy of the topic. Publications from media

organisations such as the BBC do not carry the same stringent regulations for scientific

publication as well-reputed peer reviewed articles, which must clearly cite their evidence, and

are reviewed by specialists in the particular field. Recently popular programmes and films such

“An Inconvenient Truth” and “The Great Global Warming Swindle” have shown the polarity of

opinion on the subject of global warming. Many think global warming to be a dangerous threat to

humanity, whereas some have the view that global warming is a cycle of the Earth’s climate, and

that any hype is a result of political scare-mongering. The education of students is also

increasing the amount of controversy, as climate change and other geographical elements are

often taught in a way that perpetuates outdated and incorrect information, encouraging more

ill-informed notions into the minds of newer generations. Knight (2007) suggests that as

geographical study progresses ever more quickly, and in ever more diverse directions, the text

books and knowledge of teachers cannot keep up with new discoveries made in the field. It is



important that educators and students learn from reliable and up to date sources.

Evidence for climate change is important for understanding the nature of the Earth’s

climate and also for predicting trends for the future, and constructing climate models. The

necessity for accurate data collection and understanding of the climate has lead to the creation

of bodies like the IPCC. Organisations like the IPCC create the arena for scientific debate, which

has contributed to added controversy in the media. Evidence of quaternary environmental history indicates that the climate, in the last 2.6 million years, have been characterised by rapid and

extreme alterations. Many ice ages have been shown to have occurred in this period. Evidence

for this idea is four fold. Firstly, continuing and historical records, documenting climate and so

called “proxy” indicators of climate; i.e. the growing plant life. Proxy indicators can be shown in

ice core in the form of delta oxygen 18. Secondly, geological evidence, including fossil bio

evidence. Thirdly, the geomorphological evidence, showing the change in land-forms. Lastly,

ocean cores like Vema 28 238, which illustrated 16 significant changes in climate, and ice cores

such as the “Summit” in Greenland.

The change in sea level is a very potent physical image in the issue of global warming.

the notion that coats lines and dense areas of population may be engulfed by a risen ocean creates a fear for most of the uniformed general public. The change in sea level can be affected

by elements of the geographical and ecological systems occur in some congruency with the

effects of an increased shift to warmer temperatures in the Earth’s climate. Two important

factors in the study of sea level change are the melting and accumulating of continental ice

sheets, and the thermal expansion of the ocean. In the case of ice increase and decrease, it is

apparent that more ice melt from increased temperature creates more water in the ocean, and

thus higher sea levels, and inversely the accumulation of ice affects to reduce the current sea

level. A warmer climate promotes thermal expansion of water molecules, resulting in higher sea

levels. The variations in ice melt produces a increasingly complex pattern of sea level change.

This is due to the fact that not all ice melts occur t the same time or at the same rate. This limits the theory that Global warming affects does not affect sea level change.

Evidence for sea level change is presented in the Tide Gauge Records, which date back

to relatively recently, around 200 years or so. These records indicate the relative sea level

variation. from 1961- 2003 a trend of sea level increase has been shown, at a average rate of 1.8

mm per year. The affects of future sea level rise could present a threat to populous areas,

particularly on coastlines and small islands. Low lying islands, such as the Maldives could have

fresh water supplies contaminated by such sea level change. Global temperature and sea-level

change have been shown to be closely linked.

Change in glaciers is also an important aspect to answering the preposition that Global

warming is a controversial issue. Glaciers are an important part of global climate, as they

dispense most of the dry season water supply. Yohe (2004) makes the point that glacial

changes can affects local climates severely, in terms of communities vulnerable to floods, and

landslides that can be initiated by a melting glacier. The images of glacial melt and glacial retreat

plague media publications and broadcasts, and have influenced the opinions of many members

of the public. Yet glacial change is an immensely complex area of ongoing scientific

investigation, and so the postulation that glacial change diametrically reflects climate change is

an uncertain one. Glaciers are moderately affected by the climate, in terms of rain and snow fall,



and the temperature changes; causing more or less ice-melt. However, there are climate

independent glacial fluctuations that occur which affect the advance or retreat of the glacier

margin. It is pertinent to make clear that ice travels forwards in receding glaciers, and that it is

the position of the glacial margin that indicates if the glacier is retreating of advancing. Margin

position alteration can occur due to changes in the ice supply, and also due to the rate at which

ice is lost. If ice supply is increased, and the temperature is reduced the glacier continues to thicken, as the flow of ice slows down. If there is more melting and less ice, there will be a basal

deformation, as the glacier advances, elongates and thins. These changes have to be viewed

over a broad time-scale, as changes in ice gain, and in ice melt thousands of years in the past

could affect contemporary glacial change.

There are various theories as to what are the most primary causes of climate change

and global warming. These diverse scientific ideas increase the amount of debate and

controversy related to the subject, and intensify the desire of the public for scientists to work to

remedy the effects of the most accountable causes of climate change. Three major

suppositions are astronomical forcing, solar forcing and forcing due to volcanic eruptions.

Forcing due to astronomical causes proposes that changes in the Earth’s oribtal eccentricity, obliquity and precession have significant resultant effects on the global climate. The eccentricity

of the earth’s orbit alters around every 100,000 years, this altering eccentricity coincides with

Vostok ice core records which show a near 100,000 year cycle of regular climate change.

Milankovitch, an advocator of this theory thought that deviations in the earth’s relative position to

the sun reduced or increased the distribution of the sun’s energy on the earth surface. Imbrie, et

al. (1976) argue that this in turn has a bearing on the ice sheets in the northern hemisphere,

the expansion and reduction of which is believed to impact heavily on the global climate.

Solar forcing relates to the varying amounts of energy radiated to the earth from the sun.

The theory intimates that the absence of sunspots means that the sun is radiating less energy to

earth than if there were sunspots present. Shindall, et al. (2001) suggest that evidence for any possible link with climate alteration is from the Maunder Minimum (1645-1715) in which the

recorded absence of sunspots coincided with a abnormally colder climate, thus indicating a

diminishment of the sun’s energy to earth. In the two previous theories the strength of these

astronomical factors to cause serious climate change is doubted by many.

The third theory is that volcanic activity and volcanic eruptions over earth’s history have

contributed to episodic cooling in the earth’s climate. It is thought that the expulsion of dust and

sulphurous elements into the atmosphere; during an eruption, block a great deal of the sun’s

energy which in turn cools the earth’s temperature, quite substantially. Examples of

corroborating the notion of this theory include the eruption of Mt Pinatubo in the Philippines in

1991. In this instance many tonnes of sulphur and dust were discharged, resulting in a cooling of

almost 0.6ºc. Briffa et al. (1998) indicate that the eruption of Tambora in Indonesia in 1815

influenced the description in historical archives of 1816 being “the year without summer”. This

eruption is also related to the little ice age experience in the late 18th and early 19th century.

The global warming topic is now at it’s forefront in the mind’s of government, the media

and the general population. The public, the media, and governments wish to know the possible

future impacts of climate change, so as to be prepared for the worst possible outcome. Yet,

evidence of the disastrous effects of global warming is uncertain, much more evidence needs to



be collected over a longer time-scale to fully understand the nature of the global climate system.

At the present time some believe that global warming is directly related to the immoral expansion

of our industrial civilisation, others believe that global warming is a cyclical phenomena, the

controversy lies in that there is not enough evidence to fully prove or disprove either theory.

Reference List

Briffa, K.R., Jones, P.D., Schweingruber, F.H. and Osborn, T.J. 1998, 'Influence of volcanic

eruptions on Northern Hemisphere summer temperature of the past 600 years.', Nature, 393,

450-455.

Holden, J. 2005, Quaternary Environmental Change, J. Holden Ed, Pearson, Prentice Hall.

Imbrie, J.D., Imbrie, J., et al. 1976, 'Variations in the Earth's orbit: Pacemaker of the ice ages.',

Science, 194, 1121 - 1132.Knight, P.G. 2007, 'Physical Geography: Learning and teaching in a discipline so dynamic that

textbooks can't keep up!', Geography , Vol. 92, Issue 1, pp. 58-62.

Lowe, J.J and Walker, J.C. 1997, Reconstructing Quaternary Environments, Second Edition,

Longman, .

Shindall, D.T. and Schmidt, G.A. 2001, 'Solar forcing of regional climate during the Maunder

Minimum', Science, 294, 2149 - 2152.

Yohe, E. 2004, Sizing Up the Earth's Glaciers [online], p. 1, Available from:

http://earthobservatory.nasa.gov/Study/GLIMS/ [Accessed: 23.4.2008].

http://www.google.com/url?q=http%3A%2F%2Fearthobservatory.nasa.gov%2FStudy%2FGLIMS%2F&sa=D&sntz=1&usg=AFQjCNEtet2PpcRV5oZhZjj0azZL4CI-iQ

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Global Warming Geography Essay