Comments on: Geoengineering – damned if you do, damned if you don’t?

By: Science Educator award, Sydney talk, BNC 2 years old « BraveNewClimate

Science Educator award, Sydney talk, BNC 2 years old « BraveNewClimate — Sun, 15 Aug 2010 14:18:18 +0000

[...] little over 2 years ago, on 7 August 2008, the Brave New Climate blog, later to be shorthanded to BNC, was born. Little did I foresee the [...]

By: Towards climate geoengineering? « BraveNewClimate.com

Towards climate geoengineering? « BraveNewClimate.com — Sat, 18 Apr 2009 14:42:46 +0000

[...] too long in cutting carbon emissions. For earlier discussions of this topic on BraveNewClimate, see here and [...]

By: G.R.L. Cowan, H2 energy fan 'til ~1996

G.R.L. Cowan, H2 energy fan 'til ~1996 — Mon, 19 Jan 2009 12:48:10 +0000

If we estimate the per-tonne cost of pulling down CO2 as 2x, where the maximum acceptable cost is x, we can quickly reach the conclusion that it's a bad idea. Dr. R.D. Schuiling estimates the cost of pulverizing and dispersing alkaline earth silicate minerals such as olivine as US$10-15 per tonne of atmospheric CO2 captured. Pulverized limestone would be expected to capture only half as much, but perhaps is sufficiently easier to pulverize -- 25 kWh of electricity per tonne for olivine, if I recall correctly -- to justify its use. Sulphate dispersal does not need to be extensively considered, because it is SACTCAR. Several discussions of CCS start with the premise that all methods are SACTCAR, and prove it by avoiding enumeration of the silicate and carbonate dispersal methods; that is to say, they are long-windedly deceptive by omission. I seem to recall the COSMOS article was one such. --- G.R.L. Cowan (How fire can be domesticated)

By: Ranking geo-engineering options for mitigating climate change impacts « BraveNewClimate.com

Mon, 19 Jan 2009 07:01:56 +0000

[...] geo-engineering options for mitigating climate change impacts (for an earlier discussion on BNC, see here). The paper is entitled “Ranking geo-engineering schemes“, by New Zealander Philip [...]

By: JohnTons

JohnTons — Sun, 05 Oct 2008 06:20:08 +0000

For Australia the reality of Climate Change is a warning that we have no choice but to develop a lifestyle that is not dependent on the exploitation of finite resources. In coming months we will see a roll out of ministerial statements drooping with gravitas and all with much the same message: “we would love to take action on climate change but the global economic situation is such that now is not the right time.” We need to be prepared for this and invest time and energy in developing alternative low to zero carbon futures. We can start by promoting technologies that will make more efficient use of our energy.

By: Agmates Rural News » Blog Archive » Is PM Kevin Rudd another James Hansen Desciple?

Thu, 18 Sep 2008 10:28:50 +0000

[...] The Prime Minister made that statement in an unexpected and impassioned speech yesterday near the end of a long parliamentary debate on a government bill that clears the way for millions of tonnes of carbon dioxide to be stored under the sea. [...]

By: Target atmospheric CO2 levels, not vague emissions reductions « BraveNewClimate.com

Tue, 16 Sep 2008 01:15:17 +0000

[...] time to load another arrow into the bow and shoot again at the target – as quickly as possible, and be prepared to shoot again if we miss. But instead, we’ve turned our back on the archery range and are running in the opposite [...]

By: Ronald Brak

Ronald Brak — Thu, 14 Aug 2008 06:56:55 +0000

I’m afraid that liming the oceans doesn’t sound very practical to me. If it takes 1.5 cubic kilometers of limestone to remove a billion tons of CO2, then it would take over 30 cubic kilometers of limestone to remove the CO2 we add to the atmosphere each year. That means humanity would have to increase the total amount of mining activity it performs by about five times. If the cost of mining, heat treating and distributing limestone is only $40 a ton, then it would cost about $500 to remove one ton of carbon from the atmosphere. Since low quality sorghum, which is about 50% carbon, can often be bought for under $200 a ton it might be cheaper and easier to simply pour grain into the ocean in an area of sedimentation.