Well Warmair if that is the figure being used by IPCC then they may well have it wrong.

Ozdoc said;
Pr Aleklett has not studied in depth the 'reserves' not yet discovered.

Well maybe, but what is known that all new discoveries are usually
quite small as it is believed that all large deposits were long ago
discovered.
Have a look at the declining size of new discoveries.
No more Saudi Arabias are on the likely horizon.

Bazz referring back to my last post the big problem is coal, the known reserves are at least 860,938 Million tonnes, a ball park figure in this range is widely accepted but if you wish google it here:-

https://www.google.com.au/?gws_rd=cr#q=coal+reserves+worldwide

If we burn all the coal, we will produce over 2000 billion tonnes of CO2 but it will only take 600 billion tons of CO2 get us over 550 ppm in the atmosphere. At 550ppm it is estimated global temperatures would have increased by 2 deg C . Basically we could probably avoid the worst aspects of climate change, by not burning anymore coal, cutting back on oil, burning more gas instead, and adding reasonable amounts of renewables into the mix.

Bazz, what is known is that Aleklett concedes that his 3 yr old estimates are just that, "estimates".

"all new discoveries are usually quite small" - really, Bazz?

Are you suggesting 'methane clathrates' are quite small as a fuel resource, or the Arctic or South American oil fields, or the African coal, oil & gas 'discoveries', or the vast world-wide CSG reserves are quite small?

No Bazz, please wait for more informative analysis - much better than your second guessing on matters that you want to believe.

Warmair, I understand where you are coming from - but may I respectfully suggest you leave 'back-of-the-envelope-maths' out of it? Just wait till AR5 is fully released. Cheers.

ozdoc,

Good advice.

: )

¨but may I respectfully suggest you leave 'back-of-the-envelope-maths' out of it? Just wait till AR5 is fully released.¨

This is exactly the problem I have with Aleklett he is using a whole pack of envelopes. It has been accepted for at least a decade, that burning all the known reserves of fossil fuels will push CO2 levels well over anything that the scientists consider safe. This is a trivial problem to demonstrate. It has nothing to do with IPCC scenarios, which in reality deal with when we are likely to reach various milestones on the way to stuffing up the climate. The question is can we safely burn all the known reserves of fossil fuels the answer is clearly no. In my view science without numbers is basically just opinions.

http://www.monbiot.com/2009/05/06/how-much-should-we-leave-in-the-ground/

Just a comment on a couple of things.
First peak world coal is expected around 2025 to 2030.
The reason that it seems to differ so markedly to what you believe is
coal reserves is because it that it takes into account the cost of mining.
Australia is in the fortunate position of having plenty of cheaply
accessible coal.

Re oil, well the year in which the greatest amount of oil was discovered is 1963.
Ever since then each year the discoveries are smaller.
In 1983 the amount of oil consumed exceeded the amount discovered.
The graphs have drawn further and further apart since.

If you find it, just sit and contemplate it, the conclusion is clear.

ps Shale hardly touches the sides.

I would put the graph up here but pity that facility is not available.
Try Googling Colin Campbell I think it was part of an article he wrote.