Global Warming Debate
Global Warming Debate
Humans have known about global warming for many years.
MANY people think that our concern about carbon dioxide and global warming is a modern preoccupation driven by the attention of high-profile personalities, politicians and green activists. But Al Gore did not discover global warming. Nor did Tim Flannery, Peter Garrett, Greenpeace or Malcolm Turnbull. Scientific concern about global warming is not new.
A single scientific paper, published more than three decades ago, can place the discussions about climate change into historical perspective. Tomorrow it will be 35 years since the leading science journal Nature published a review paper entitled "Man-made carbon dioxide and the 'greenhouse' effect", by the eminent atmospheric scientist J. S. Sawyer, director of research at the United Kingdom Meteorological Office.
In four pages, Sawyer summarised what was known about the role of carbon dioxide in enhancing the natural greenhouse effect leading to warming at the earth's surface, and made a remarkable 28-year prediction of the warming expected to the end of the 20th century. His prediction can now be compared with what has been observed. We can also compare his review of the science in the early 1970s with that in the latest (2007) assessment from the Intergovernmental Panel on Climate Change.
After summarising recent calculations of the likely impact of increasing carbon dioxide concentrations on global surface temperature, Sawyer concluded that the "increase of 25 per cent in carbon dioxide expected by the end of the century therefore corresponds to an increase of 0.6 degrees in world temperature - an amount somewhat greater than the climatic variations of recent centuries".
Examination of the global surface temperature over the latter part of the 20th century shows that in fact the temperature rose about 0.5 degrees between the early 1970s and 2000. Considering that global temperatures had, if anything, been falling in the
Humans have known about global warming for many years.
MANY people think that our concern about carbon dioxide and global warming is a modern preoccupation driven by the attention of high-profile personalities, politicians and green activists. But Al Gore did not discover global warming. Nor did Tim Flannery, Peter Garrett, Greenpeace or Malcolm Turnbull. Scientific concern about global warming is not new.
A single scientific paper, published more than three decades ago, can place the discussions about climate change into historical perspective. Tomorrow it will be 35 years since the leading science journal Nature published a review paper entitled "Man-made carbon dioxide and the 'greenhouse' effect", by the eminent atmospheric scientist J. S. Sawyer, director of research at the United Kingdom Meteorological Office.
In four pages, Sawyer summarised what was known about the role of carbon dioxide in enhancing the natural greenhouse effect leading to warming at the earth's surface, and made a remarkable 28-year prediction of the warming expected to the end of the 20th century. His prediction can now be compared with what has been observed. We can also compare his review of the science in the early 1970s with that in the latest (2007) assessment from the Intergovernmental Panel on Climate Change.
After summarising recent calculations of the likely impact of increasing carbon dioxide concentrations on global surface temperature, Sawyer concluded that the "increase of 25 per cent in carbon dioxide expected by the end of the century therefore corresponds to an increase of 0.6 degrees in world temperature - an amount somewhat greater than the climatic variations of recent centuries".
Examination of the global surface temperature over the latter part of the 20th century shows that in fact the temperature rose about 0.5 degrees between the early 1970s and 2000. Considering that global temperatures had, if anything, been falling in the