Here's the research/math. According to F. A. Davis's Medical Dictionary, the average male exhales approx. 550 CC's of mixed gases upon every exhale. It turns out, only about 28 CC's are actually Carbon Dioxide (CO2). There are about 6.6 Billion inhabitants of the Earth, so:

28CC'sX6.6Billion= 184.8 Trillion CC's of CO2 released when the whole world takes a breath.

1 CC of CO2 equals about 0.00000198 Kg's so: 184.8 Trillion CC's X 0.00000198 equals 365,904 Kg's of CO2.

The average man breaths approx. 13 times a minute. Which translates to approx. 6.8 million times per year. Multiply that to the total amount of CO2 humans exhale in one breath, and it turns out that approx 2 Trillion Kg's of CO2 is exhaled a year, just by humans.

For a reference, in 2004 The Carbon Dioxide Information Analysis Center in Oak Ridge Tennessee found that in 2004 humans had burned approx. 7910 million Metric tons which equals 7,910,000,000 Kg's (approx 8 Billion Kg) burned since 1751.

The ratio of Carbon burned (over 250 years) compared to the ratio of Carbon exhaled (over one year) looks something like this: 8Billion Kg's to 2 Trillion. Which simplifies to: 8 to 2,000 Kg's. To put this on a more universal scale, there was approx. 400 Million Kg's of CO2 burned in the year 2004. Compared to the annual exhalation rate, the simplied ratio looks like this: 1/5,000. So for every Kg of CO2 burned, five thousand Kgs was exhaled.

So in conclusion, humans exhale WAY more CO2 than we could possibly burn in 250 years, in just one short year. And that is just humans exhaling, what about our furry little friends of the animal kingdom? They exhale CO2 also.