Page 9 - Managing Global Warming

Why do we have global warming? 1

Trevor M Letcher * ,†,1
*Laurel House, FosseWay, Stratton on the Fosse, Somerset, United Kingdom,
†
University of KwaZulu-Natal, Durban, South Africa
1
Corresponding author: trevor@letcher.eclipse.co.uk

Chapter Outline

1.1 The greenhouse effect 3
1.2 The root cause of global warming 5
1.3 Other causes of global warming and climate change including global cooling 7
1.4 Indicators of climate change 9
1.5 Why we must act now 10
1.6 What must be done to reduce global warming? 10
1.7 Are we making progress in reducing global warming? 11
1.8 Conclusions 13
References 14

1.1 The greenhouse effect

The concept of the greenhouse effect goes back to the 1820s, when Joseph Fourier
suggested that some component of the earth’s atmosphere was responsible for the
temperature at the surface of the earth. He was researching the origins of ancient
glaciers and the ice sheets that once covered much of Europe [1].
Decades later, Tyndall followed up the Fourier’s suggestion, and used an apparatus
designed by Macedonio Melloni to show that CO 2 was able to absorb a much greater
amount of heat than other gases. This fitted in with Fourier’s concept and pointed to
CO 2 as the component in the atmosphere that Fourier was looking for. The Melloni
apparatus was called a thermomultiplier and was reported in 1831 [2,3]. Tyndall’s
results were published in references [4,5]. As a result, Tyndall can be named as the
discoverer of the CO 2 greenhouse gas effect.
Linking CO 2 in the atmosphere to the burning of fossil fuels was to be the last link
in the chain in understanding the reasons for the ice ages and also our own climate
change. In the 1890s, Svante Arrhenius, an electrochemist, calculated that by reducing
the amount of CO 2 in the atmosphere by half, the temperature of Europe would be
lowered by about 4–5°C. This would bring it in line with ice age temperatures. This
idea would only answer the question of why the ice age formed and then retreated,
if there were large changes in atmospheric composition and in particular, changes
in CO 2 concentration. At much the same time, also in Sweden, a geologist, Arvid

Managing Global Warming. https://doi.org/10.1016/B978-0-12-814104-5.00001-6
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