Source: Forward Essay by Naomi Oreskes on page xvi in the 2011 book Climate Denial Heads in the Sandby Haydn Washington and John Cook.
Notes: In this forward essay by Naomi Oreskes, she writes,
"Climate sensitivity isn't just a theory, it's an observation." (her emphasis)
Oreskes writes that Irish scientist John Tyndall first indicated carbon dioxide (CO2) is a powerful greenhouse gas back in the 1850s. Even more, CO2 presence in the atmosphere, even at extremely low concentrations, is vital for Earth's life sustaining climate.
Since then, numerous other studies confirmed the high sensitivity of Earth's climate to atmospheric CO2. Since the 1880s, we increased atmospheric CO2 by one-third. The result is an increase in average global temperature of close to 1 degree Celsius.
Orseskes goes on to say "As for the source of the recent increase in CO2, that was worked out in 2003 – and it's not volcanoes." She notes two different forms of carbon: C-12 and C-13." Orsekes then states,
"Plants and material derived from them, notably coal, have much lower concentrations of C-13 than in other materials, including the CO2 emitted from volcanoes. Isotope geochemists Prosenjit Ghosh and Willi A. Brand measured the C-13 content of the atmospheric CO2 and show that as the total CO2 rose, the C-13 fell. This result is what you'd expect if that CO2 came from fossil fuels."
Yet, Austrialian professor of mining geology Ian Plimer, puts invisible, underwater volcanoes as the source for increased atmospheric CO2. Naomi Oreskes response:
"Besides the obvious point that he is asking us to believe in something that no one has ever seen, felt or observed in any form, he asks us to disbelieve what scientists have seen and measured. It's a bit like asking us to believe in Santa Claus after we have seen our parents putting the presents under the tree."
Image Source: iwitness.wthr.com