Very interesting article Man’s Contribution to Global Warming | The Foundry … . But i don’t agree 100% with it as I need to search for other sources on this topic. But still thank you for posting. Visited your website Monday will look forward to vi…

BTW – Greenland lies where the North Atlantic meets the Arctic Sea, and didn't get its name from lush vegetation but rather from a deception by Eric the Red (Leif’s daddy). That (moderate climate) geography populated by Norsemen in the Middle Ages is on Western shore and represents a very small part of the total (very cold) land.

The source of the figure is:

"A Global Warming Primer"

http://www.ncpa.org/pdfs/GlobalWarmingPrimer.pdf
And indeed on page 7 it says that humans contribute approximately 3.4% of annual CO2 emissions.

To arrive at that figure, you need to divide the human emissions by the total emissions from all sources. So what are all those sources? The bibliography at the end of the Global Warming Primer points to this document as the main reference for the chart on page 7:

"Sense and Sequestration: The Carbon Sequestration Cycle Explained"

http://liberty.pacificresearch.org/docLib/2007020…

Look at Table 1 on page 9, specifically the column "Estimated carbon flux into atmosphere". The total is 217.1 Pg C/yr. The human contributions are 5.5 from Fossil fuel burning, and 1.6 from Forestation/deforestation, for a total of 7.1 Pg C/yr.

So the percentage from human contributions is 7.1 / 217.1 x 100 = 3.27% (close enough to the 3.4% in the chart).

But think about it: it's a meaningless number, as it fails to take into account the fact that the largest natural sources of emissions are also the largest *sinks* – as is made very clear from the right hand column "Estimated carbon movement out of atmosphere" of Table 1 on page 9 of "Sense and Sequestration".

To draw an analogy: suppose two people, Henry and Nancy, open a joint bank account. At the start of every month, Nancy deposits $1000, but also withdraws $995 dollars during the month, so her net monthly contribution is $5. Meanwhile, Henry contributes $45 each month and makes no withdrawals. Over the course of one year, the bank balance goes up by 12 x $50 = $600.

Now, suppose you ask what percentage of that $600 increase is attributable to Henry's activity.

Well, since the net total monthly increase is $50, and $45 of that is from Henry, Henry accounts for $45/50 x 100 = 90% of the increase. Obvious.

Suppose you have an accountant who decides to ignore the withdrawals and only take into account the deposits. Here's what you get:

Henry's total deposits = 12 x $45 = $540

Nancy's total deposits = 12 x $1000 = $12000

Total deposits = $12540

Fraction of increase due to Henry = $540 / $12540 x 100 = 4.3%

I would fire that accountant, wouldn't you?

But what's been done to arrive at the 3.4% figure in the chart. It uses the source values ("deposits" or flux of CO2 into the atmosphere), but ignores the sinks (the "withdrawals" or movement of CO2 out of the atmosphere)!