From CNN: Surveyed scientists agree global warming is real.

The results of a University of Illinois survey of scientists include the following:

• 90% of the scientists surveyed agreed that global temperatures have risen compared to levels from before 1800.
• 82% agreed that human activity been a significant factor in this increase of mean global temperatures.
• 97% of climatologists surveyed agreed with anthropogenic global warming (AGW).
• At the other end of the spectrum, only 47% of petroleum geologists agreed with this.

The researchers chose scientists listed in the the American Geological Institute’s Directory of Geoscience Departments, 2007 edition.

Geologists in general have been more skeptical about AGW than have other scientists, though I’ve noticed a considerable shift on this in publications of the Geological Society of America and the American Geological Institute. Two reasons for this skepticism that have been proposed are:

1. A deep historical perspective. Geologists know that Earth’s climate has fluctuated throughout its history by purely natural means, and that a number of factors have caused this, including changing brightness of the sun, changing oceanic circulation patterns, plate tectonics, and cyclical variations of Earth’s orbit. The Quaternary Period, i.e. the past 1.8 million years, has had an especially variable climate, with long glacial maximum periods, punctuated by interglacial periods, such as the one we live in now.
2. The close association of geology to the fossil fuel industries. Perhaps there is something psychological here, with a denial that the oil, gas, and coal that we are so closely tied to are the cause of something bad.

I think it is significant that 97% of climatologists surveyed believe global warming is real and that humans have been a significant factor in this. But climatologists will continue to need the input of geologists to gain a fuller understanding of how Earth’s climate works, in both the short term and long term.

Grace and Peace