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'Educated' opinions on climate change part 2 40

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Some quick sums

2 billion first worlders use say 10 times the energy per capita of 5 billion third worlders

so total energy useage is 25 units.

We want to reduce that by 10% (random target)

That leaves us with 22.5 units.

I can see no moral justification for the following, but let's restrict the third worlders to merely trebling their energy usage. So they've taken 15, leaving 7.5 for us.

That's about 4 units each, ie we need to (a) prevent the third world from increasing their energy usage overmuch, and (b) reduce our own energy useage by 60%. (b) might be containable, but I wouldn't be buying Boeing shares, or expecting to see much concrete or aluminium around, (a) is politically preposterous.

The reward for this Stakhovanite (and unlikely) effort will be a slight reduction in the rate of increase of atmospheric CO2.

Coincidentally I read this this morning. A fairly neat summary of an Australian perpsective on the global warming thing.





Cheers

Greg Locock

SIG:please see FAQ731-376 for tips on how to make the best use of Eng-Tips.
 
GregLocock said:
3) Anthropogenic CO2 is a significant contributor to (2)
4) (2) is a dominant contributor to (1)
.....
My argument is that 3 is duff, anthropogenic CO2 is a small percentage of the natural carbon cycle, which is an enormous feedback cycle (that may or may not include temperature)
Click to expand...

Let's look at #3.


Wiki tells me the total amount of CO2 in the air today is 3,000 gigatonnes.
The increase in the last century or so is 30% or about 1,000 gigatons.

We are spewing about 30 billion tons per year into the air from burning fossil fuel. Let's not even add in the effect of deforestation and stick with 30 billion tons per year as conservatively low number for man's effect on CO2.

At 30 billion tons per year, how many years would it take to create the amount of the increase (1,000 gigatons) ?

1000 gigatons / 30 billion tons/yr ~ 30 years
(Double check my math – and forgive me if I have intermixed tons and metric tonnes or whatever– this is just an order of magnitude discussion).

Well, we have certainly been dumping CO2 into the air for more than 30 years, but not at the full 30 gigaton/yr rate. And some of it has decayed (I think the half-life is 40 years). So, our contribution gets close but maybe not quite enough to explain the whole thing

But there is also the temperature feedback cycle. Increased CO2 brings increased temperature brings increased CO2 etc. Surely that has played a role in the CO2 increase since we have been getting warmer over this last century (that was your item 1 so I don't have to argue that one thank goodness). So the "feedback" of increased temperature might serve to magnify the added CO2. Rolling this back into the equation, might cancel out the factors like decay and make the conclusion that man has caused the increase reasonble.

But now you cry foul... how do I know the CO2 caused the temperature to increase and not the other way around? Well let's think about this. CO2 and temperature move togehter in the historical record in the same direction. CO2 historically lagged temperature. But at the particular point in time (2008), the CO2 concentration is HIGHER THAN AT ANY TIME IN THE LAST 800,000 YEARS, while the temperature is nowhere near it's high point of that period. It suggests that the CO2 is not fully driven by temperature this time... on this occasion they are again moving together, but this time the initiator / leading /driving variable is CO2 and the temperature is the lagging / driven feedback variable. (a break from the historical pattern but one that is expected if CO2 were driven by an influence other than temperature.... i.e. mankind)


Well, I will certainly admit the last paragraph about feedback is a lot of supposition. And the last paragraph discussion also neglects the fact that there certainly are other factors which can drive temperature change (a fact that NO-ONE DISPUTES). But even without the feedback discussion of the last paragraph, we can see that we are in the ballpark – 30 years addition at the current rate (neglecting feedback and the variation in addition rate) gives us the 30% increase in CO2 that we have seen in the last century or so.

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Maybe a picture is worth a thousand years.

Blue = temperature
Red = CO2.

Look at the unprecedented increase in CO2 at the very end of the graph. You believe the change occurred (that is your item #2).

Something clearly changed dramatically at the end of this graph to have that effect on CO2.

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"Maybe a picture is worth a thousand years."
Musta been a Freudian slip.

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How about that sea weed bloom in China?
 
The Chinese attribute it to rising water temperatures.
But that's them, not me. And they didn't say it was global.

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The quote I was referring to:
Australian sailing team director Michael Jones said with the climate on the Yellow Sea coastline warming up, the rise in sea temperatures was causing the massive algae build-up.
Click to expand...
An Australian, not a Chinese person.
Other reports of course mention pollution, natural causes etc.
Not a very relevant subject, just wanted to head off any accusation that I was making stuff up.

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Increasing industrialisation means: power generation: means cooling water use from rivers: means local increases in water temperature.

By the way, as I understand it, the "greenhouse gas effect" is not linear. As CO2 concentration increases, the effect plateaus. And CO2 still lags temperature.
Potent stuff though (not when compared to water vapour, methane etc.), its there at 0.03%. Of course, NOX is there at 0.01% but is said to be 3 times more powerful as a green house gas than CO2.

Of course, not much we can do about NOX.
While fossil fuel burning accounts for a significant proportion of anthrogoenic CO2 release, it is less than 1% of athropogenic NOX; most is from agriculture. Anthropogenic NOX is around 2 terratons per annum and natural NOX is around 15 terratons per annumn; mostly from bacterial action and electrical storms.


JMW
 
I didn't think that "NOx" (NO and NO2) was a significant greenhouse gas, but Nitrous Oxide (N2O) is. (NOx contributes to ground-level ozone / smog and is a pollutant emitted by combustion engines)


 
So do I understand correctly that we need more smoke to reduce solar radiation?
 
If someone suggested that, I didn't see it. NOx and smoke are different things, if that's what you were referring to.

 
He may have been referring to the NOx/particulate tradeoff, having confused NOx with N2O?

- Steve
 
N2O is a different issue which should showup as acid rain, which to an extent is good for plants.

Smog, or smoke reduces radiation from sun light by reflecting it. It also should reflect infra red light back to the earth. So what is the net result hotter or cooler?


 
Actually, I'm quoting the environmentalists at Oceana.com.
The more provocative statements are harder to find as they have edited many of them out now.
Note that they want to see distillate fuels used because of the impact on global warming yet distillates will produce more CO2 due to the added refining.

JMW
 
hmm... so they say that NOx reacts to form O3, and that O3 is a greenhouse gas, and that N2O itself is a greenhouse gas. As far as I know, NOx is not considered in any GHG trading schemes currently, whereas N2O is (with a multiplier to give a tons CO2 equivalent). Anyone have further info on that?
 
See also the Friends of the Earth proposition supporting Senator Boxter.
These guys are not, of course, authorities on anything but that doesn't stop them making it up as they go.

JMW
 
Our TV advertising is telling us we can save the world by following the Supreme Master Ching Hai.
Life is simpler in Australia.
(NB I would not recommend that anyone actually follows Ms Hai, you won't save the world.)
 
sulphur-something crystals from burning dirty coal form albedo-increasing emissions. As we clean up the smokestacks on dirty coal power-stations we will reduce the Earth's albedo and so increase the solar laod on the Earth.

Apparently.



Cheers

Greg Locock

SIG:please see FAQ731-376 for tips on how to make the best use of Eng-Tips.
 
Interesting thought.
According to ARIC (DEFRA's information website): “In the early 1960s, winter smoke concentrations in Manchester averaged at more than 250mgm-3. Today the typical urban annual mean for smoke is 10-40mgm-3.
The amount has decreased dramatically due to technical industrial air pollution control, the decline in the use of coal for domestic purposes and the general shift of power stations and industries from town and city centres to more rural locations.

Er, does that mean that the environment has been significantly improved? Yes. Not by 10% or 12% but significantly. In my lifetime. So why do the environmentalists insist we are making things worse than ever before in our history?

One of the contributors to this was the clean aor act and the change to smokeless fuels. Subsequently we have the "rush to gas" and the introduction of gas fired central heating.
I remember well those days when the first one up, shivering in the cold, would have to clean grates, make fire starters from rolled up newspaper, fetch coal and start the fires. Another sheet of newspaper to close off the front of the fire place would help with the draft and with care you could get the fire going without filling the room with smoke or setting the draft enhancing newspaper alight.
One of the things I miss is the smell of chimney smoke on a cold winters day.

Of course, all that smoke pollution was killing millions and every day they'd drag the bodies out of the houses and bury them in huge mass graves. No, wait a minute, maybe that was MAFFI (DEFRA) during the foot and mouth outbreak? So why do the Greens make me think that is the case today? They're messing with my mind. And yes, the changed albedo has resulted in this ten year low that is "temporary" and nothing at all to do with the sun which is so absolutely stable that it has no influence on warming or cooling of the climate.

JMW
 
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