Philip Sutton suggested I contact you via your blog with regard to a query about equating ppm with ‘% emission reduction targets’.

The correspondence is below. But I can’t attach a chart in Excel to this blog. Is there an email address I can send it to?

The question is:

Attached is a chart that I’ve extracted from ‘Six Degrees’ by Mark Lynas. The original shows ppm with corresponding avaerage global temp rises.

I’m trying to find out how the chart equates to the targets Rudd/Garnaut express in’ % reduction by X date’ from some base.

The Greens don’t seem to know and I’m wondering who might. Any ideas?

I think it’s important because it’s pretty clear from ‘Six Degrees’ that we don’t want to have to cope with more than a 2 degree increase (Jim Hansen would be comfortable with even less now that the rate of arctic and antarctic ice melt is accelerating).

And I believe that in order to communicate the urgency and implications of temp change, we need a simple chart that non-scientists can easily understand and that compares apples and apples by understanding targets in terms of ppm.

Otherwise the politicians get away with ‘smoke and mirrors’ as usual………../Chris

From: Philip Sutton [mailto:Philip.Sutton@green-innovations.asn.au]
Sent: Sunday, 2 November 2008 2:58 AM
To: Chris Sanderson
Cc: Robert Rosen
Subject: Re: Mark Lynas’ ‘Six Degrees’

Hi Chris,

Mark Lynas’ ‘Six Degrees’ is a great book. Extremely valuable. But, because climate science keeps developing ‘Six Degrees’ is now out-of-date in one key area. It now appears that climate sensitivity could be twice as high ~6 ºC rather than ~3 ºC, which means that longer term impacts will occur at approximately half the forcing previously anticipated. So Mark Lynas’ equilibrium temberatures will be produced by much lower CO2 levels.

A climate scientist who is grappling with this is Barry Brook at Adelaide Uni. His blog can be found at:
http://bravenewclimate.com/

Cheers, Philip

——————

I was wrong about air capture, having left out a seriously energetic s6tep in the process. I calculate that it would be about twice as espensive as biochar. The least cost solution appears to be olivine weathring:

ftp://ftp.geog.uu.nl/pub/posters/2008/Let_the_earth_help_us_to_save_the_earth-Schuiling_June2008.pdf

which at worst is no more expensive than biochar burial and at best possibly only $(US)51 per tonne of carbon removed.

————
Biochar is usually considered as a soil conditioner. As such it is typically worked into the top 30+ cm of the soil. Tests have shown that about half of it, over a few decades, returns to the active carbon cycle; the remainder lasts ‘indefinitely’, a few to hundreds of centuries. Deep burial maakes a artifical coal seam, lasting for multiple millions of years.

I’ve read elsewhere that bio-char is extremely good at binding nutrients to the soil. Here is an important quote from the Catalyst story:

By adding char, we’ve shown that we can reduce nitrous oxide emission five-fold.

Therefore you can cut back on your use of fertilisers. Plants grow more vigorously, absorbing more CO2 from the atmosphere.

The full transcript of the Catalyst program is available here:

http://www.abc.net.au/catalyst/stories/s2012892.htm

When they were talking about the avocado farm they showed the char being spread on top of the grass growing under the trees. They didn’t dig it into the soil.

If you’ve got the time have a look at the documentary I referenced above.

…and burned it for fuel instead of an equivalent amount of coal, could we make enough to replace all coal

Not a good option. You’re just putting all that carbon absorbed by growing stuff back into the atmosphere. This exactly why solar thermal, geothermal, wind, wave, photovoltaics and demand reduction through more efficient use of energy are necessary.

If we were to make as much char as possible, and burned it for fuel instead of an equivalent amount of coal, could we make enough to replace all coal? If not, how much could we replace? What do the answers to these questions say about the practicality of reducing emissions with biochar production in the first place?

The questions keep coming, but I always get back to these first few…

more expensive, less I think, than deeply burying biochar

In a recent Catalyst program they showed bio-char being spread on top of the soil and in the video I referenced all of the terra-preta is shown in the top metre or so of the soil. I’m not sure that you have to bury it at all.

I would have thought that there would be a lot more interest in this post. Seems everyone is worried about the financial turmoil. I get the feeling that people really don’t understand how big a problem global warming is.

One can only hope that the politicians get smart very quickly and start supporting the development and mass production of the sort of progressive, green technologies that are mentioned here. As Barry said, it will help alleviate both problems.

The best scheme to permanently and relatively inexpensively remove carbon from the active carbon cycle is via air capture:

http://www.ucalgary.ca/news/september2008/keith-carboncapture

My preliminary estimate is in the $(US)30–38 range per tonne of CO2; an important advantge is that the captured CO2 need not be transported long distances, only possibly the electricity to power the capture units.

If the goal is to permanently remove carbon from the acdtive carbon cycle, this is no more expensive, less I think, than deeply burying biochar.

http://video.google.com/videoplay?docid=8993313723654914866

The potential of this technology to terra-form our land using productive and sustainable practices is great. And the big plus is that it sequesters carbon naturally. This has to be one of the many technologies that research and development dollars should be spent on. Not this fake CCS stuff.