Apparently the biggest man influenced contributor are cows and other livestock, far more than industry and automotive. And then volcanoes give off more in minutes then we do in years.
So what?
I suggest you look up metastability and tipping point, and then re-read TESLACOIL's contribution below.
Whilst I don't agree with the previous post to this, I also personally can't accept the above.
If we look at the earth over geologic time we know that historically there has been much more CO2 in our atmosphere than exists today. For example, during the Jurassic Period, average CO2 concentrations were about 1800 ppm or about 4.7 times higher than today. The highest concentrations of CO2 during all of the Paleozoic Era occurred during the Cambrian Period, nearly 7000 ppm - about 18 times higher than today.
The Carboniferous Period and the Ordovician Period were theonly geological periods during the Paleozoic Era when global temperatures were as low as they are today.
The late Ordovician Period was also an Ice Age while at the same time CO2 concentrations then were nearly 12 times higher than today - 4400 ppm.
According to greenhouse theory, Earth should have been exceedingly hot. Instead, global temperatures were hardly any different than today. Clearly, other factors besides atmospheric carbon influence earth temperatures and global warming.
No climatologist, nor anyone with a basic grounding in physics, would claim otherwise. However, MMGW naysayers like to claim that others do so claim, because it gives their arguments an apparent way in.
Why do you think it weakens the relevance of tipping points? If anything, it strengthens it.
PHP: Is that a fact?
What 'current' global warming thing?
With regard to atmospheric carbon and it's relationship with global warming, what tipping point?
Completely agree
Not true at all.
"In 2009, the CO2 global average concentration in Earth's atmosphere was 387 parts per million by volume (ppmv). This is 103 ppmv (36%) above the 1832 ice core levels of 284 ppmv" (Wikipedia).
Carbon dioxide (CO2) forms approximately 0.04% of the nominal 5,000,000 gigatonnes of gas and aerosols that comprise the Earth's atmosphere.
The problem with this is that the CO2 levels are always naturally fluctuating due to causes that root back to the sun. If we look at further back CO2 levels (hundreds of millions of year) we can see that CO2 levels have been much higher.
This graph is only over the past 70mill years, but you can still see that CO2 levels have dropped since then:
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