Originally Posted by BRussell
greg, I believe you're the one who's mincing words here. The statement says that the warming in the past 50 years has been caused by increased greenhouse gases. There's no way that greenhouse gases have increased in the past 50 years in this fashion from any cause other than human activity.
From Wikipedia, "Some greenhouse gases occur naturally in the atmosphere, while others result from human activities. Naturally occurring greenhouse gases include water vapor, carbon dioxide, methane, nitrous oxide, and ozone. Certain human activities, however, add to the levels of most of these naturally occurring gases."
Furthermore, "Atmospheric carbon dioxide derives from multiple natural sources including volcanic outgassing, the combustion of organic matter, and the respiration processes of living aerobic organisms; man-made sources of carbon dioxide come mainly from the burning of various fossil fuels for heating, power generation and transport use. It is also produced by various microorganisms from fermentation and cellular respiration."
Just because you don't fully understand global warming, doesn't mean you're qualified to laugh off points.
According to the United States Department of Energy (http://www.eia.doe.gov/oiaf/1605/gg00rpt/tbl2.html)
, there's 7.1 billion metric tons of human made carbon dioxide.
Compare this to the 150 billion metric tons of natural carbon dioxide.
A better example is table 1 here: http://www.geocraft.com/WVFossils/greenhouse_data.html
(While I contest the general premise of the page, the numbers are accurate).
Man-made contributions are only 14.8% of total CO2 additions to the atmosphere. If we completely stopped all driving and manufacturing and lived as a hunter gatherer society, we STILL would barely put a dent in the rate that CO2 is increasing.
Blaming humans isn't helpful nor useful. At best, we can only cut down our emissions. Even if we could stop our emissions, that doesn't keep the world itself from building up carbon dioxide.
The report itself very clearly states that global warming is being caused by human activity. The following is the entire summary from the report itself
Exactly. It is. It's also being caused my NON-human activity. What part of this is difficult for you to understand? The report doesn't deny this. Only you seem to be.
It's crystal clear what they're saying, and the paper I cited (and I believe icfireball was referring to) says that all scientists publishing in this field appear to agree with this.
The paper you cited states nothing to that fact. The article you cited says that most scientists generally agree. I generally agree.
What you are trying to do is take an excellent claim, that humans affect global warming. This is true, and pretty much impossible to deny.
What you are then doing is saying that humans are SOLELY responsible for global warming. Hardly anyone is saying this, especially not any article you've cited. More importantly, since your article, more evidence has come out that the role of humans is smaller than previously believed.
The point is that there really, really, genuinely, honest-to-goodness IS a bona fide scientific consensus that global warming is occurring and is being caused by human activity. Any controversy is generated by people who are not researchers in this field. It's really very similar to where we are with biological evolution. Scientists who study the field endorse it, those who criticize it are outside of the field itself.
No, they're pretty different.