"Jim Logajan" wrote:


6. Human activity currently releases 6 billion tons of CO2 per year.

The evidence is clear that something is wrong with the above claims.


...and shouldn't that be 6GT of *carbon* each year? Has the professor
confused CO2 with carbon?

According to the U.S. EPA the claim seems to be in the right order of
magnitude, though is indicates the U.S. alone produces the equivalent of
~6 billion tons of CO2 per year:

http://yosemite.epa.gov/oar/globalwarming.nsf/UniqueKeyLookup/RAMR6P5M5M/$File/06FastFacts.pdf



But according to the USGS, the total global human contribution of CO2 is 4
times that amount:

http://volcanoes.usgs.gov/Hazards/Wh...html#reference


"Comparison of CO2 emissions from volcanoes vs. human activities.
Scientists have calculated that volcanoes emit between about 130-230 million
tonnes (145-255 million tons) of CO2 into the atmosphere every year (Gerlach,
1999, 1992). This estimate includes both subaerial and submarine volcanoes,
about in equal amounts. Emissions of CO2 by human activities, including fossil
fuel burning, cement production, and gas flaring, amount to about 22 billion
tonnes per year (24 billion tons) [ ( Marland, et al., 1998) - The reference
gives the amount of released carbon (C), rather than CO2.]. Human activities
release more than 150 times the amount of CO2 emitted by volcanoes--the
equivalent of nearly 17,000 additional volcanoes like Kilauea (Kilauea emits
about 13.2 million tonnes/year)"


It appears to me that the professor *has* confused carbon with CO2, and his
argument collapses, no?