John, list, et al:
Apologies if this comes to you twice. Am still at the conference hotel
and have had trouble sending. This time much shorter.
> On Aug 25, 2016, at 9:08 AM, Ronal W. Larson <rongretlar...@comcast.net>
> wrote:
>
> John, list et al:
>
> Re your almost last sentence(emphasis added):
> “BTW, I would also recommend an ambition to restore land and ocean
> productivity to their levels of a few thousand years ago, before mankind
> started to denude soils and sea of nutrients.”
> I am pleased to report that we have just finished the 2016 Biochar
> conference at Oregon State University (Corvallis, OR), and that great
> progress has been made since our last in 2013. I would guess at least three
> times more commercial presence and activity than then. Many new reports of
> cost effectiveness - even as little as one-year payback.
> I would amend your sentence to express an ambition not to restore but
> to double.
>
> Ron
>
>
>> On Aug 25, 2016, at 6:25 AM, John Nissen <johnnissen2...@gmail.com
>> <mailto:johnnissen2...@gmail.com>> wrote:
>>
>> Dear Benjamin,
>>
>> I should have mentioned olivine crushing because it has a huge role to play
>> in bringing down the level of CO2 in the atmosphere, for example directly by
>> scattering on the beach or indirectly by promoting diatoms or soil
>> improvement.
>>
>> Re emissions reductions, I probably made a mistake in my earlier email,
>> because I was assuming the maximum rate of emissions reduction, suggested to
>> be 7% per annum, was an exponential reduction with a halving of emissions
>> every 10 years and thus never reaching zero. But the rate will be more
>> linear than that, making it feasible to obtain an emissions reduction to 30%
>> in 10 years and to near zero in 15 years.
>>
>> As well as this reduction, starting now, I propose immediate aggressive CDR
>> over the next 10 years (including olivine crushing, biochar and ocean
>> fertilisation) to obtain an equalisation of drawdown with emissions, thus
>> achieving a zero net input of CO2 to the atmosphere, aka "carbon
>> neutrality", by ~2025. This will be the peak of CO2 level in the
>> atmosphere. The CDR will be exactly offsetting 30% the current level of
>> emissions, assuming that maximum 7% annual reduction is maintained over the
>> 10 years.
>>
>> CDR should continue to be ramped up over the following 20 years, to obtain a
>> halving and then a quartering of the climate forcing due to excess CO2 in
>> the atmosphere, i.e. taking the level from its peak in ~2025 down to 340 ppm
>> and then to 310 ppm.
>>
>> If IPCC were to accept this as a legitimate "representative concentration
>> pathway", then there could be the ambition of climate restoration by 2050,
>> with CO2 and CO2eq back to near pre-industrial levels resulting in a
>> cessation of global warming well below the <2C target.
>>
>> In addition to CDR, there would need to be measures to reduce non-CO2
>> forcing agents: to reduce fugitive methane: to suppress methane from the
>> Arctic and from wetlands; to reduce black carbon, especially from tundra
>> fires; and, most urgently, to save the sea ice, prevent disintegration of
>> the Greenland Ice Sheet and restore albedo in the Arctic. The ambition
>> might be to restore the levels of albedo and greenhouse forcing agents to
>> their pre-industrial levels by 2050.
>>
>> BTW, I would also recommend an ambition to restore land and ocean
>> productivity to their levels of a few thousand years ago, before mankind
>> started to denude soils and sea of nutrients.
>>
>> I am looking forward to your response.
>>
>> Kind regards, John
>>
>>
>> On Tue, Aug 23, 2016 at 9:00 AM, Schuiling, R.D. (Olaf) <r.d.schuil...@uu.nl
>> <mailto:r.d.schuil...@uu.nl>> wrote:
<Snip>
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