paypuh said:
Please show me these sources you have that equate our CO2 production with the amount given off by volcanoes.
Can't be exactly done (every eruption depends of so many variables), but here's some material.
http://www.britannica.com/EBchecked/topic/632130/volcano/24453/Volcanic-eruptions
"The most common volcanic gases are water vapour, carbon dioxide, sulfur dioxide, and hydrogen sulfide. Small quantities of other volatile elements and compounds also are present, such as hydrogen, helium, nitrogen, hydrogen chloride, hydrogen fluoride, and mercury. The specific gaseous compounds released from magma depend on the temperature, pressure, and overall composition of the volatile elements present. The amount of available oxygen is of critical importance in determining which volatile gases are present. When oxygen is lacking, methane, hydrogen, and hydrogen sulfide are chemically stable, but when hot volcanic gases mix with atmospheric gases, water vapour, carbon dioxide, and sulfur dioxide are stable.
Some volcanic gases are less soluble in magma than others and therefore separate at higher pressures. Studies at Kilauea in Hawaii indicate that carbon dioxide begins to separate from its parent magma at depths of about 40 km (25 miles), whereas most of the sulfur gases and water are not released until the magma has nearly reached the surface."
From wikipedia, volcanoes.
"Large, explosive volcanic eruptions inject water vapor (H2O), carbon dioxide (CO2), sulfur dioxide (SO2), hydrogen chloride (HCl), hydrogen fluoride (HF) and ash (pulverized rock and pumice) into the stratosphere to heights of 16?32 kilometres (10?20 mi) above the Earth's surface. The most significant impacts from these injections come from the conversion of sulfur dioxide to sulfuric acid (H2SO4), which condenses rapidly in the stratosphere to form fine sulfate aerosols. The aerosols increase the Earth's albedo?its reflection of radiation from the Sun back into space - and thus cool the Earth's lower atmosphere or troposphere; however, they also absorb heat radiated up from the Earth, thereby warming the stratosphere. Several eruptions during the past century have caused a decline in the average temperature at the Earth's surface of up to half a degree (Fahrenheit scale) for periods of one to three years ? sulfur dioxide from the eruption of Huaynaputina probably caused the Russian famine of 1601 - 1603.
Volcanic activity releases about 130 to 230 teragrams (145 million to 255 million short tons) of carbon dioxide each year"
One teragram is 1 000 000 000 kg or 1 000 000 metric tons, equalling these numbers to 130 to 230 million metric tons.
And of mud volcanoes: http://www.springerlink.com/content/v2v02q5176q64161/
"Global gas emissions are provisionally estimated to exceed 27 billion cubic metres per year, of which more than 23 billion (15.8 Tg) is methane. More than 70% of this is from short-lived eruptions, about 30% of which ignite to produce flames tens or hundreds of metres high. The majority of the methane is emitted by submarine mud volcanoes, most in deep water. About 11.4 Tg per year is lost to the hydrosphere, but a tentatively estimated 3.6 Tg per year escapes to the atmosphere"
And from a NASA article:
http://geology.com/nasa/human-carbon-dioxide/
"Human activities add a worldwide average of almost 1.4 metric tons of carbon per person per year to the atmosphere. Before industrialization, the concentration of carbon dioxide in the atmosphere was about 280 parts per million. By 1958, the concentration of carbon dioxide had increased to around 315 parts per million, and by 2007, it had risen to about 383 parts per million. These increases were due almost entirely to human activity."
That 1.4 metric tons per person adds up to (6.77 billion humans assumed) 9 478 000 000 metric tons or 9.487 billion metric tons of carbon/year.
If even 10% of that carbon produced by human activity is in the form of carbon dioxide, we are still talking about 4 to 7 times to production of volcanic eruptions.
And carbon dioxide actually weights more than just carbon, so if the given output of human activity was pure carbon, the numbers are skewed even more to the side of human activity. One carbon-12 atom weighs around 12 g/mol, carbon dioxide weighs 44,0 g/mol. 12 grams of carbon therefore translates to 44 grams of carbon dioxide. or every gram of carbon translates to 3,667 grams of carbon dioxide.
This means that 900 million metric tons (slightly less than 10% of total human activity carbon production) of carbon, when combined with oxygen, is 3 300 000 000 metric tons or 3.3 billion metric tons of carbon dioxide. That is over ten times that of estimated maximum average volcanic activity produces (that was 230 million metric tons).
