Oops! Damned Decimal Places!

Ok. I promise that this is my last rant for a while about global warming and carbon emissions, but I need to give you some stats, because there's some confusion about exactly how much CO2 25 billions tonnes is, and I might have put a decimal in the wrong place last week.

So I whipped out the trusty Excel spreadsheet, and this time, I figured it out as a proportion of the total of the world's atmosphere. I did this because a)I was bored, b)I need to get out more, and c)I was filling in for Amanda, our brilliant retail manager, on a day when nothing much else was happening.

Whatever. I'm sure there could have been a more productive use of the energy consumed by my braincells, so I'm sorry, Al Gore, if all that thought energy has contributed to global warming on Titan.

Ok... here it is... for anyone remotely interested, and get ready for some numbers so big they're incomprehensible...

The total weight of the world's atmosphere is around five million billion tonnes, which is the number 5 with fifteen zeros on the end. Of course, you already knew that, didn't you?

Depending on what part of the world you're in, I think you can call it five thousand trillion tonnes, of five quadrillion tonnes. Or not. Let's just call it "a lot". You can work it out by multiplying the surface area of the earth, which is 510 million sq km, by the air pressure (which is the weight of the air, 1kg per sq cm (14.7lb/sq in), or 10,000 tonnes per sq km.).

Which means the total man made CO2 going into the atmosphere every year (if you were paying attention, you'll remember that as 25 billion tonnes a year) is 0.0003%, or 3 thousandths of one percent of the total volume.

This is about 3% of the total CO2 pouring into the atmosphere from all sources, which means natural CO2 accounts for 97%.

Here are some more stupid meaningless comparisons...

If I wanted to show it on a graph, the line would stretch from Sydney to LA, and the man made CO2 would be the first 40cm (about 15.5") of that line.

If it was a proportion of total Government spending in 2007, it would run whatever country you live in for about a hundred and three seconds out of the year.

People, these numbers are about as easy to understand as your mobile phone plan.

Here's a thought though... breathing by every human on earth produces about 1kg of CO2 a day each, which, given our population of five billion people, accounts for a staggering 7% of the total man made CO2 emission around the world...

...so if we could just get rid of some people... now wouldn't THAT be an inconvenient truth!