Gregory Many thanks. I would like to know more about the CROPS program if you have a reference
But a propos "when the trees die", they don't die under commercial forrestation but get cut down when growth slows and the rate of increase of value falls below the operator's cost of borrowing. When that happens, if there is co-produced fuel and timber, is that some fossil fuel gets left in the ground and some other timber elsewhere gets left standing (hopefully in natural biodiverse forest), an ongoing process for "chipping away at atmospheric CO2 yearly" that can also support both REDD and biodiversity objectives. In a 'normal' commercial plantation there are equal area stands of all ages of maturity from just planted to due to be felled next year. Annual growth shifts each stand one year towards maturity, so that the average age of stand is half the maturity age and there is a total standing stock of carbon equal to approximately half of the maximum possible if all the stands were left unfelled after growing to maturity and then left to die (which would yield a zero return on investment). While a new forest is growing towards the maturity of its first stand, and a new stand is planted each year so as to eventually result in a normal forest, the "chipping away" comes from annual average growth of the forest, which ceases when the first stand is felled since thereafter annual felling removes as much C as is captured by the annual growth of the rest of the forest. Increased "chipping away" results from routing the fuel fraction through one of the negative emissions systems, biochar or BECCS, which results in C being stored as nearly pure C in the soil or as CO2 deep underground, as well as in leaving fossil fuel underground. Decreased chipping away results if the trees left standing in natural forests die off. A forthcoming paper by Len Ornstein suggests (from memory - some time since I saw the draft) that about 1Gt of carbon annually could be kept from the atmosphere if an organised program existed for sequestering C that would otherwise be returned to atmosphere following natural treefall. Peter ----- Original Message ----- From: <[email protected]> To: <[email protected]>; <[email protected]>; <[email protected]>; <[email protected]> Sent: Sunday, May 17, 2009 4:20 AM Subject: Re: [geo] Re: [clim] Fwd: White/Cool Roofs Memo to MEF (Major Economies Forum) Peter: I might point out that commercial reforrestation works hand in hand with deep ocean sequestration as well. Forest growth can hold CO2 for centuries, but when the trees die, much of their debris can be sequestered in deep water, a la the CROPS program. Chipping away at the CO2 yearly makes sense, and each seasonal year we neglect doing it, that CO2 will be with us a long time: Sequestration by installment. Gregory Benford . . . (snipped by PR) --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en -~----------~----~----~----~------~----~------~--~---
