MP: Of course we affect the earth, but we are nothing cmpared to nature itself, things like volcanos spew out enormous amounts of bad gasses that must be several magnitudes more than the entire mankind.
Also not true. Why are you spreading counter-knowledge and misinformation? It's not hard to get the facts.
Volcanic versus anthropogenic CO 2 emissions
Do the Earth’s volcanoes emit more CO 2 than human activities? Research findings indicate that the answer to this frequently asked question is a clear and unequivocal, “No.” Human activities, responsible for a projected 35 billion metric tons (gigatons) of CO 2 emissions in 2010 (Friedlingstein et al., 2010), release an amount of CO 2 that dwarfs the annual CO 2 emissions of all the world’s degassing subaerial and submarine volcanoes (Gerlach, 2011).
The published estimates of the global CO 2 emission rate for all degassing subaerial (on land) and submarine volcanoes lie in a range from 0.13 gigaton to 0.44 gigaton per year (Gerlach, 1991; Varekamp et al., 1992; Allard, 1992; Sano and Williams, 1996; Marty and Tolstikhin, 1998). The preferred global estimates of the authors of these studies range from about 0.15 to 0.26 gigaton per year. The 35-gigaton projected anthropogenic CO 2 emission for 2010 is about 80 to 270 times larger than the respective maximum and minimum annual global volcanic CO 2 emission estimates. It is 135 times larger than the highest preferred global volcanic CO 2 estimate of 0.26 gigaton per year (Marty and Tolstikhin, 1998).
In recent times, about 70 volcanoes are normally active each year on the Earth’s subaerial terrain. One of these is Kilauea volcano in Hawaii, which has an annual baseline CO 2 output of about 0.0031 gigatons per year [Gerlach et al., 2002]. It would take a huge addition of volcanoes to the subaerial landscape—the equivalent of an extra 11,200 Kilauea volcanoes—to scale up the global volcanic CO 2 emission rate to the anthropogenic CO 2 emission rate. Similarly, scaling up the volcanic rate to the current anthropogenic rate by adding more submarine volcanoes would require an addition of about 360 more mid-ocean ridge systems to the sea floor, based on mid-ocean ridge CO 2 estimates of Marty and Tolstikhin (1998).
There continues to be efforts to reduce uncertainties and improve estimates of present-day global volcanic CO 2 emissions, but there is little doubt among volcanic gas scientists that the anthropogenic CO 2 emissions dwarf global volcanic CO 2 emissions.
For additional information about this subject, please read the American Geophysical Union's Eos article "Volcanic Versus Anthropogenic Carbon Dioxide" written by USGS scientist Terrence M. Gerlach.