While I'm not sure that the atmosphere's volume is constant, I will give slasher the benefit of the doubt.

It seems that sea-level pressure changes have been recorded for some time in a lot of places and has been compiled into large dataset called the HadSLP2. Given your knowledge about pressure/temperature relationships in the atmosphere, can you tell us what the HadSLP2 dataset says about it slasher? Does it confirm global temperature changes or not?

Bugsy

<< While I'm not sure that the atmosphere's volume is constant, I will give slasher the benefit of the doubt.>>

The Ideal Gas Law slasher bangs on about is a reasonable response from a high school physics/chemistry student. I can understand how his comment would sow the seeds of doubt.

Nevertheless, it is also reasonable to assume that a student does not have enough experience or tutaledge in more advanced physics/chemistry. On a personal level, I thought I knew calculus until I was confronted with tensor calculus.

Slasher has not discovered anything new that scientists have not been aware of and while it may seem nice to him to describe the atmosphere in terms of a simple linear model,unfortunately, its not. The climate system is profoundly non-linear.

When I said "the atmosphere is not a closed system", it was not only alluding to volumes (implicit in the gas law) but also other external factors that must be taken into account in regard to heat transfer e.g. sources/sinks. I expect to be amused by his answer to your challenge.

I can only suggest that if people want to learn about atmospheric physics or radiative transfer, they should go to a prime source, rather than an opinion forum.

To others whinging about "alarmist" writing in risk mitigation scenarios:
1. I said I don't know about the 100 meters, they might be right when one includes modelling for thermal expansion as well as ice-water melt. It also depends on time scales.

2. I doubt some of the IPCC's models because there simply isn't the oil, gas, and coal to exponentially increase our consumption to the year 2100. When I hear the IPCC say things like (for example only, haven't bothered to look up the actual statement for a while) "by 2100 we'll be consuming 150 million barrels of oil a day"... I just laugh. We're about to hit peak oil at somewhere around 90 million barrels a day and from then on it's all downhill. Gas follows a few years later, then coal maybe around 2025 to 2050.

Now global warming is already BAD, we need to get down under 350 ppm. Burning just all the remaining OIL would be serious enough, let alone all the gas and COAL cook cook the planet 5 times over. But I'm talking about economic incentives to change suddenly overwhelming nice "greenie" incentives to change. Once we pass the peak of these resources their price skyrockets in a market competing for them. All I'm saying is that I'm looking forward to what the market comes up with after this occurs! You guys will no longer be able to complain about government conspiracies to tax us, it will become a profound economic necessity!

3. You are all actually sounding REALLY uninformed about the scariest *realistic* global warming scenario that could have enormous ramifications for the world's politics in just a few decades. So if you're busy debunking climate alarmism, why haven't you gone for the biggie? Maybe you don't even know about it?

4. Real science evolves, but dogmas stay the same and keep trotting out the same old myths. Some of you are just repeating the same tired old narratives which are so unutterably boring and predictable. Fiddling while Rome burns.

I have to hand it to you, Eclipse Now: I thought there were some elegant rhetorical gymnasts on this forum, but you make them look like rank amateurs.

Of course some scientists aren't being alarmists - they're not being alarmist enough!

The IPCC represents the consensus view of every scientist who's ever lived ever, and absolutely cannot be wrong about anything - until Eclipse Now disagrees with it!

Well, I think I have learned "the difference between some greenie activist making a big flamboyant statement to attract attention to the absolutely worst case scenarios, and a more solid statement of scientific probability" ... you've just given us a prime example.

EN

There is no doubt humanity is conducting an *experiment* that has not been done before. The *experiment* can’t be repeated and we don’t have a control against which to test it. Therefore, it makes sense to proceed with caution, risk management if you like.

Anyway, are you familiar with the work of Susan Solomon (co-chair on WG1 for the IPCC’s AR4)?
Earlier this year she and some colleagues published a paper showing that reducing CO2 concentrations will take a very, very long time - so long in fact that they describe it in terms of irreversibility. The so called ‘deny-n- delay brigade’ jumped on this research and used it as an argument not to mitigate GHG emissions – what’s the point was their catch-cry. Their response of course was/is just silly.

Solomon et al were saying that we (humanity) have to find a way to limit our GHG emissions given that we are already committed to an embedded increase in CO2 concentration, because if we don’t, we will just have to get used to high levels – and the concomitant problems, of which I am sure you are well aware of.

You say “we need to get down under 350 ppm.” To suggest this is fine, but if you understand the implications of Solomon et al, you must also understand that your statement is just as naive as the ‘deny-n- delay brigade’s call to do nothing. If you do not accept the conclusions of the Solomon paper, perhaps you could tell me why not.

Regardless, I think it will be difficult enough to limit the CO2 concentrations to 450 ppm, given the projected increase in world population to 9.5 billion by 2050.

I will say I too am bothered by the UN’s Special Report on Emission Scenarios. I am not an econometrician but I suspect they (like economists) have difficulty with the modelling. Climate modelling is very different.

Here is a link to the Solomon et al paper:

http://www.pnas.org/content/early/2009/01/28/0812721106.full.pdf

Hi Q&A,
none of my previous comments were targeted at you but at those whining about "alarmism".

So I guess it started me thinking about what is alarmist? Is the IPCC alarmist when it talks about huge volumes of fossil fuels being used in 2100... when no such volumes of fossil fuels exist on earth to delay peak fossil fuels till after 2100? Or is the IPCC NOT being alarmist enough because their political processes, slowed by the Saudi's and other interests, have left its models far behind the climate consensus as expressed by the leaders in their fields?

So when you say... "Of course some scientists aren't being alarmists - they're not being alarmist enough!" I think I'm inclined to agree.

I guess I was trying to say to the others "Sure, I can see problems with the IPCC models..." but the bottom line is I think they're actually not alarmist enough because they're still running on the 450ppm model.

Anyway, did Solomon deal with biochar?
What about painting our roofs white?
What about moving to economical Gen4 nuclear reactors that Dr Barry Brook always goes on about, and running our car fleet on "Better Place" battery-swap vehicles from that (coming to Canberra in 2012 as a large scale trial).

Better Place are ONLY using clean wind energy.

Surely there's stuff we can do to limit what we emit, change the albedo of our cities, and suck Co2 out of the air and into our farmland soil where it will do us some good? Surely there's always hope, even though the sceptics here STILL haven't mentioned what could happen to India and China?