[NileQueen]

John Mason, on 19 February 2012 - 09:54, said:

Another ice-age would solve your population-problem, but they develop very very slowly indeed, and given that the last decade has been the warmest on record, there ain't much sign of it happening! What would we do? Most likely have more wars to accommodate those who were displaced!

I'd certainly be very wary about even more geo-engineering (which is what AGW basically is) - we would need to be absolutely 100% certain of the outcome - which in science is never the case when looking to the future. If we were 97% certain that nothing would go wrong, would we justify gambling the whole planet on that??

Cheers - John

The Little Ice Age onset started in 25 yrs from 1275 to 1300 A.D.

Read Miller et al. 2012 Abrupt onset of the Little Ice Age triggered by volcanism
and sustained by sea-ice/ocean feedbacks. GEOPHYSICAL RESEARCH LETTERS, VOL. 39, L02708, doi:10.1029/2011GL050168, 2012

[John Mason]

Jo, I'm talking about the major glaciations, compared to which that was a passing blip!

Cheers - John

[NileQueen]

Nigel Bolton, on 18 February 2012 - 21:59, said:

The paragraph in boldface is an excellent paragraph, and one which the individual can work towards, rather than always assuming that others will do for you. If one is really serious about being non wasteful, then the home is a good place to start.

All our kitchen scraps goes on the compost heap, what cannot be composted is left under the rook colony tree. I have glass jam jars I have kept for over 20 years. Each year, freshly made homemade jam or chutney gets placed into them and is subsequently consumed. Growing ones own veg means uber-freshness and no road miles. That we cannot grow, we try and buy fresh, and with no packaging if possible.

Before Patrick came along, we could put our two weekly output to the bin men in one supermarket carrier bag. It is a shame that no one has come up with an ethical way of processing used nappies.

N.

Sounds great Nigel, but some of us live in apartments with no garden and no compost heap. I will buy veggies from the Farmer's Market when it starts up again, and I guess that
is the next best thing.

Moving 6 times in 10 years makes it impossible to keep jam jars and yogurt containers to reuse but it's a good idea if you can do that.

[NileQueen]

John Mason, on 19 February 2012 - 11:48, said:

Jo, I'm talking about the major glaciations, compared to which that was a passing blip!

Cheers - John

Conditions were such that LIA finally warmed after several hundred years 1300 to late 1800s.
You would not be thinking of it as a "blip" if it happened in your lifetime.
If this happens in the future, you don't think it would have an effect on the population?

[Peter H]

NileQueen, on 19 February 2012 - 11:55, said:

Conditions were such that LIA finally warmed after several hundred years 1300 to late 1800s.
You would not be thinking of it as a "blip" if it happened in your lifetime.
If this happens in the future, you don't think it would have an effect on the population?

So, the MWP was pre 1300?

Anyway, the LIA was, globally, much less of a change than AGW is likely (indeed probably is) to be, given it was at most less than a degree Celcius of cooling.

[Nigel Bolton]

StephenS, on 18 February 2012 - 23:50, said:

Ah, but they have (in New Zealand, anyway):
http://www.envirocomp.co.nz/

The really ethical way of course is not to use disposable ones in the first place (said the man who's never had to care for a small baby).

The above is a brilliant web-shite and should be read and understood by all those with or about to have small children. I am surprised that this form of technology has not been developed here in the UK, as the final product appears safe to use to fertilise crops.

I wonder what the costs are for running such a plant here in the UK? The web pages suggest the processing site covers not that large an area. However, it is unlikely that nimbyism is as rife in NZ as it is here in the UK, and therein lies the problem.

Using reusable 'terries' in the home may not be that ethical. One still needs to flush away the 'poo', and one needs to accumulate enough nappies to make for an ideal sized wash. This requitres using lots of water (potentialy an increasingly scarce resource), and the nappies have to be heated to high temperatures to kill the bacteria.

N.

[John Mason]

NileQueen, on 19 February 2012 - 11:55, said:

Conditions were such that LIA finally warmed after several hundred years 1300 to late 1800s.
You would not be thinking of it as a "blip" if it happened in your lifetime.
If this happens in the future, you don't think it would have an effect on the population?

It probably would have quite serious consequences, especially if rainfall patterns also changed around the world. However, in the UK, a full-on glaciation would see almost all of Wales and England north of the Midlands plus all of Scotland under an ice-sheet over a kilometre thick on places. Such things do not develop overnight, but nevertheless anybody can see the consequences if something like that were to occur. The general view is that it will not because CO2 forcing would no longer be over-ridden by Milankovitch forcings at current levels - during interglacial-glacial transitions CO2 typically fell from 280 down to 180ppm as a negative feedback loop, just as they acted as an amplifying feedback loop on the way back out of glacials. At nearly 400ppm CO2 and rising, reglaciation appears most unlikely - apart from the physics, palaeoclimate shows that the last time levels were thus there were no UK glaciations.

Cheers - John

[scrapemedic]

I thought that the co2 in the oceans was in the deep ocean and therefore not available to be released because of warm surface temps.

[NileQueen]

scrapemedic, on 19 February 2012 - 17:30, said:

I thought that the co2 in the oceans was in the deep ocean and therefore not available to be released because of warm surface temps.

If the oceans warm, it is thought that they cannot hold as much CO2 there and it remains in the atmosphere.

colder oceans can sequester more CO2, warmer oceans hold less...

John I am well aware it takes longer for a LGM type ice age. You assume ice would cover the UK again, but why didn't Siberia get iced?

[scrapemedic]

But warm oceans encourage growth of plankton, which dies and sinks to the deep ocean, thereby taking carbon to the bottom again.

[ldavidcooke]

Hey Liz,

It depends on the air/water interface temperature and surface mixing. Clear away polar ice, increase SSTs to within a few degrees of 0C and increase the average windspeeds 10%. Now change the synoptics such that the polar circle orbiting high pressure waves are interspaced with sever cyclonic waves and you have a massive uptick of surface water CO2 content...

As to deep ocean, hmmm, unlikely, CO2 at high pressure and near freezing temperatures would more likely solidify and precipitate out of solution. It may be we are confusing CO2 with warmer ocean temperatures. It is more likely for the thermocline to increase 0.6 deg C then the CO2 level to go up @9% in the last 50 years...

[John Mason]

Chris Lloyd, on 19 February 2012 - 17:28, said:

But surely the lower Co2 levels were due to sequested Co2 in the oceans and conversely as it warmed back up the oceans released the Co2 back into the atmosphere.

Surely, it is as simple as that isn't it John.

Climate drives Co2 levels - not the other way round.

Not exactly: Milankovitch Cycles drove the warming & cooling, and the CO2 released e.g. from permafrost decay in transitions from glacials to interglacials amplified the warming. So you have tipping-points relative to Earth's orbital cycles and CO2 acting as an alternatively negative or positive feedback. Did I not say ages ago that it is the thermostat of the planet?

Cheers - John

[ldavidcooke]

Hey Guys,

We really do seem to have an issue of inaccurate est. wrt the weighing of the size and volume of sinks wrt CO2. At best we can est. man's output, because we measure it, all others are SWAGs...

[andre]

And so the thread goes into deep waters again. There is an awful lot going on in the oceans during the glacial transitions, as well as a lot of volcanic events. Really some random guesses dont work here. Google Raymo Lisiecki for instance. More later.