[geo] Newsletter for week 34 of 2018

[i...@climate-engineering.eu]

Title: Climate Engineering Newsletter




  


 







 



Climate Engineering Newsletter
for Week 34 of 2018



 





(new) 18.09.2018, Lecture: Climate change concerns us all (German), Amstetten / Austria
21.08.2018, Webinar: Reframing Carbon Capture and Reuse: Building a New Industry, Webinar
22.08.2018, Panel: Climate Engineering: Ethical and Political Concerns, Hamburg / Germany
5.09.2018, Lecture: Lecture on Climate Geo-Engineering, Youngstown / USA
13.-18.09.2018, Conference: WC Climate Change 2018, Rome / Italy
11.-12.10.2018, Ingilaw Symposium Geoengineering: New environmental paradigm, new legal paradigm?, Rennes / France
30.-31.10.2018, Conference: 2018 Negative Emissions Conference: The big picture of negative emissions, Canberra / Australia
10.-14.12.2018, Conference: AGU Fall Meeting 2018, Washington DC / USA
19.-23.03.2019, Workshop: Climate Change Impacts and Risks in the Anthropocene (C-CIA), Riederalp, Canton of Valais, Switzerland


(no new calls)


(no deadline), Jobs at Harvard University
(no deadline), Job at Waldron
(no deadline), Job at The Center for Carbon Removal
30.08.2018, Job at Carnegie Climate Geoengineering Governance Initiative



Santori, G.; et al. (2018): Adsorption artificial tree for atmospheric carbon dioxide capture, purification and compression
Pfrommer, T. (2018): Diverging Regional Climate Preferences and the Assessment of Solar Geoengineering
Schulz, I.; et al. (2018): Remarkable structural resistance of a nanoflagellate-dominated plankton community to iron fertilization during the Southern Ocean experiment LOHAFEX


(no new political papers)

(no new projects)


Government.no: The Norwegian Government continues with the planning of a demonstration project for CO2 capture, transport and storage
CarbonBrief: Why BECCS might not produce ‘negative’ emissions after all
GlacierHub: Solar Geoengineering Could Limit Sea-Level Rise from Cryosphere
Science News: Faster way to make mineral to remove carbon dioxide from atmosphere
Umwelt und Gesellschaft: Negative Emissions - Bearer of Hope or Trojan horse of climate policy (German)
C2G2: What we don’t know about geoengineering and biodiversity
Politico: Europe mulls stripping carbon from the skies
L'Echo: Capturing CO2 can't replace forests (French)
Phys.org: Scientists find way to make mineral which can remove CO2 from atmosphere
Telepolis: "Climate policy inaction" (German)




 



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Re: [geo] Re: MCB/cirrus stripping with particle accelerators

[Andrew Lockley]

Thanks for your question, Oliver.

The reason to use a space based system is similar to the approach for earth
observation satellites - even coverage. A satellite in GS orbit can 'see'
roughly a third to a half of the world. Because the atmosphere is thin,
compared to the size of the earth, most beam attenuation is likely to occur
in the troposphere, where 75pc of the air is. That means a satellite
mounted system would only have to penetrate a few kms of thick atmosphere,
at most.

Crudely, I'm assuming beam range and power scale together. A kW system
gives you kms, MW gives you thousands of kms. (I said GW in an earlier
email, which would be the case if you relied on lossy accelerators for high
particle energy, not high density, as Russell helpfully pointed out.)

By contrast, a ground-mounted system would have to work over distances 3-4
orders greater. A ship-based system would be technically viable, but its
slow speed would inhibit its coverage, quickly reaching local saturation -
unless you used a high energy beam to reach 1000kms or so. A high-energy
system would need to be mounted on a ship the scale of an aircraft carrier
(which has a similar power output to a 747, although much more available as
electricity). A jet or balloon system would be plausible, but would have a
beam range of perhaps ten of kms (balloons) to hundreds of kms (large
jets), necessitating potentially millions of platforms to provide global
coverage.

I'm neither a satellite engineer, nor a cosmic ray expert - so multi-order
errors are inevitable in my reasoning.

Andrew Lockley

On Mon, 20 Aug 2018, 09:29 Olivier Boucher, 
wrote:

> Dear Andrew,
>
> as I stated before, I have some doubt about observed relationships between
> cosmic ray and cloudiness and if real, the physics is very unclear. However
> I do not understand your post. If there is such an effect, then why would
> you want to shot these particles downward from space rather than upward
> from the surface. The objective would be to increase low-level cloudiness,
> wouldn't it ?
> Regards,
> Olivier
>
> There appears to be some confusion here in terms of the numbers to use.
> Most of the particles are atomic nuclei (overwhelmingly hydrogen). These
> are therefore charged, and thus are substantially attenuated by the earth's
> magnetic field. I've been unable to determine the extent, from a quick
> Google.
>
> Furthermore, a proportion of scattering attenuation occurs in the high
> atmosphere, where it's too dry to produce clouds. It may therefore be more
> effective to use lower-flying aircraft, which are less lossy by this
> mechanism - although they may have very limited beam range. Nevertheless,
> Google's project Loon shows that mass production of non-high altitude
> balloons is at least worthy of consideration - numbers can potentially
> overwhelm range disadvantages.
>
> Finally, there's the issue of energy distribution. I've been unable to
> find a source that links particle energy to cloud CCN. The number peak at
> 0.3GEv may not be representative of an efficacy peak. Certainly, highly
> energetic particles are disproportionately effective, but it's not clear
> whether their numerical rarity makes them irrelevant, overall. There are
> significant technical issues with producing high-energy particles in orbit.
> Individual particles are travelling at near light speed, and they
> experience significant relativistic effects. It therefore requires serious
> infrastructure to produce them. That's impractical for a satellite.
> However, intermediate energy accelerators could be mounted on 747-type
> platforms, and full sized accelerators could be land based. One problem
> with very high energy particles is that they're *individually* dangerous.
> The highest energy particles have the energy of a baseball travelling at
> nearly 100kmh. You can't go shooting those at airliners.
>
> Further thoughts welcome.
>
> Andrew
>
> On Mon, 20 Aug 2018, 01:55 Russell Seitz,  wrote:
>
>> The  grid-to-beam efficiency of  greater than GEV particle accelerators
>> ranges from kess than 5 % for high current systems , to as little as  0.02%
>> for superconducting colliders like the LHC.  As the global cosmic ray flux
>> is of the order of 5 GW, matching it might therefore take anywhere from a
>> hundred GW to several tens of terawatts.
>>
>> At the high end of that power range one runs into a serious feedback-
>>  the cloud nucleation cooling might be overwhelmed by extra CO2  radiative
>> forcing  from the thermal plants in the grid powering the accelerators.
>>
>> On Sunday, August 19, 2018 at 10:17:58 AM UTC-4, Andrew Lockley wrote:
>>>
>>> Cosmic rays cause cloud condensation nuclei. They are therefore believed
>>> to affect cloudiness, and therefore climate. If we made more cosmic rays,
>>> that would likely make it more cloudy. Whether this was a warming or
>>> cooling effect would depend on whether it was cirrus or cumulus clouds (NB,
>>> sometimes making cirrus ultimately 

Re: [geo] Re: MCB/cirrus stripping with particle accelerators

[Olivier Boucher]

Dear Andrew,

as I stated before, I have some doubt about observed relationships 
between cosmic ray and cloudiness and if real, the physics is very 
unclear. However I do not understand your post. If there is such an 
effect, then why would you want to shot these particles downward from 
space rather than upward from the surface. The objective would be to 
increase low-level cloudiness, wouldn't it ?


Regards,
Olivier
There appears to be some confusion here in terms of the numbers to 
use. Most of the particles are atomic nuclei (overwhelmingly 
hydrogen). These are therefore charged, and thus are substantially 
attenuated by the earth's magnetic field. I've been unable to 
determine the extent, from a quick Google.


Furthermore, a proportion of scattering attenuation occurs in the high 
atmosphere, where it's too dry to produce clouds. It may therefore be 
more effective to use lower-flying aircraft, which are less lossy by 
this mechanism - although they may have very limited beam range. 
Nevertheless, Google's project Loon shows that mass production of 
non-high altitude balloons is at least worthy of consideration - 
numbers can potentially overwhelm range disadvantages.


Finally, there's the issue of energy distribution. I've been unable to 
find a source that links particle energy to cloud CCN. The number peak 
at 0.3GEv may not be representative of an efficacy peak. Certainly, 
highly energetic particles are disproportionately effective, but it's 
not clear whether their numerical rarity makes them irrelevant, 
overall. There are significant technical issues with producing 
high-energy particles in orbit. Individual particles are travelling at 
near light speed, and they experience significant relativistic 
effects. It therefore requires serious infrastructure to produce them. 
That's impractical for a satellite. However, intermediate energy 
accelerators could be mounted on 747-type platforms, and full sized 
accelerators could be land based. One problem with very high energy 
particles is that they're *individually* dangerous. The highest energy 
particles have the energy of a baseball travelling at nearly 100kmh. 
You can't go shooting those at airliners.


Further thoughts welcome.

Andrew

On Mon, 20 Aug 2018, 01:55 Russell Seitz, > wrote:


The  grid-to-beam efficiency of  greater than GEV particle
accelerators ranges from kess than 5 % for high current systems ,
to as little as  0.02% for superconducting colliders like the
LHC.  As the global cosmic ray flux is of the order of 5 GW,
matching it might therefore take anywhere from a hundred GW to
several tens of terawatts.

At the high end of that power range one runs into a serious
feedback-  the cloud nucleation cooling might be overwhelmed by
extra CO2  radiative forcing  from the thermal plants in the grid
powering the accelerators.

On Sunday, August 19, 2018 at 10:17:58 AM UTC-4, Andrew Lockley
wrote:

Cosmic rays cause cloud condensation nuclei. They are
therefore believed to affect cloudiness, and therefore
climate. If we made more cosmic rays, that would likely make
it more cloudy. Whether this was a warming or cooling effect
would depend on whether it was cirrus or cumulus clouds (NB,
sometimes making cirrus ultimately removes water, resulting in
less cirrus)

Cosmic rays are almost all protons, with an typical energy
peak distribution of 0.3GEv. (4.8×10^−11  J). No idea if
that's the right energy for CCN, but we can tweak that later.

Creating artificial cosmic rays is possible, using a linear
particle accelerator. This is similar to an ion thruster, as
used in space probes.

To affect climate, you'd probably have to get densities of the
order of 1/s/sqm (more on that, later).

360 million square kilometers of ocean is 360tn sqm or
3.6x10^14sqm. You don't really want to send particles into
people, and the cleaner air over the oceans makes them more
effective.

A kilo of hydrogen contains 6x10^26 protons.

That means 1kg of H2 gives you enough material for 1.6x10^12s
= roughly 50 years - so a satellite could easily carry enough
material to do the job.

Power is 3.6x10^14 x 4.8x10^-11J/s = 17kW - again, well within
what a satellite could muster (roughly 100sqm of solar panels,
at around 20% panel efficiency (conservative) and 50pc
conversion (made up) efficiency).

Cheap satellites are about $50m - well within the capabilities
of a rich philanthropist. Even if this is not cheap, it's
still only perhaps 500m

If I'm out by 5 orders (1 ray per sq cm, not per sq m each
second), then that's only 10,000 satellites. That's expensive,
but not outlandish. Superficially, that would be $500bn at the

Re: [geo] Re: MCB/cirrus stripping with particle accelerators

[Andrew Lockley]

There appears to be some confusion here in terms of the numbers to use.
Most of the particles are atomic nuclei (overwhelmingly hydrogen). These
are therefore charged, and thus are substantially attenuated by the earth's
magnetic field. I've been unable to determine the extent, from a quick
Google.

Furthermore, a proportion of scattering attenuation occurs in the high
atmosphere, where it's too dry to produce clouds. It may therefore be more
effective to use lower-flying aircraft, which are less lossy by this
mechanism - although they may have very limited beam range. Nevertheless,
Google's project Loon shows that mass production of non-high altitude
balloons is at least worthy of consideration - numbers can potentially
overwhelm range disadvantages.

Finally, there's the issue of energy distribution. I've been unable to find
a source that links particle energy to cloud CCN. The number peak at 0.3GEv
may not be representative of an efficacy peak. Certainly, highly energetic
particles are disproportionately effective, but it's not clear whether
their numerical rarity makes them irrelevant, overall. There are
significant technical issues with producing high-energy particles in orbit.
Individual particles are travelling at near light speed, and they
experience significant relativistic effects. It therefore requires serious
infrastructure to produce them. That's impractical for a satellite.
However, intermediate energy accelerators could be mounted on 747-type
platforms, and full sized accelerators could be land based. One problem
with very high energy particles is that they're *individually* dangerous.
The highest energy particles have the energy of a baseball travelling at
nearly 100kmh. You can't go shooting those at airliners.

Further thoughts welcome.

Andrew

On Mon, 20 Aug 2018, 01:55 Russell Seitz,  wrote:

> The  grid-to-beam efficiency of  greater than GEV particle accelerators
> ranges from kess than 5 % for high current systems , to as little as  0.02%
> for superconducting colliders like the LHC.  As the global cosmic ray flux
> is of the order of 5 GW, matching it might therefore take anywhere from a
> hundred GW to several tens of terawatts.
>
> At the high end of that power range one runs into a serious feedback-  the
> cloud nucleation cooling might be overwhelmed by extra CO2  radiative
> forcing  from the thermal plants in the grid powering the accelerators.
>
> On Sunday, August 19, 2018 at 10:17:58 AM UTC-4, Andrew Lockley wrote:
>>
>> Cosmic rays cause cloud condensation nuclei. They are therefore believed
>> to affect cloudiness, and therefore climate. If we made more cosmic rays,
>> that would likely make it more cloudy. Whether this was a warming or
>> cooling effect would depend on whether it was cirrus or cumulus clouds (NB,
>> sometimes making cirrus ultimately removes water, resulting in less cirrus)
>>
>> Cosmic rays are almost all protons, with an typical energy peak
>> distribution of 0.3GEv. (4.8×10−11 J). No idea if that's the right
>> energy for CCN, but we can tweak that later.
>>
>> Creating artificial cosmic rays is possible, using a linear particle
>> accelerator. This is similar to an ion thruster, as used in space probes.
>>
>> To affect climate, you'd probably have to get densities of the order of
>> 1/s/sqm (more on that, later).
>>
>> 360 million square kilometers of ocean is 360tn sqm or 3.6x10^14sqm. You
>> don't really want to send particles into people, and the cleaner air over
>> the oceans makes them more effective.
>>
>> A kilo of hydrogen contains 6x10^26 protons.
>>
>> That means 1kg of H2 gives you enough material for 1.6x10^12s = roughly
>> 50 years - so a satellite could easily carry enough material to do the job.
>>
>> Power is 3.6x10^14 x 4.8x10^-11J/s = 17kW - again, well within what a
>> satellite could muster (roughly 100sqm of solar panels, at around 20% panel
>> efficiency (conservative) and 50pc conversion (made up) efficiency).
>>
>> Cheap satellites are about $50m - well within the capabilities of a rich
>> philanthropist. Even if this is not cheap, it's still only perhaps 500m
>>
>> If I'm out by 5 orders (1 ray per sq cm, not per sq m each second), then
>> that's only 10,000 satellites. That's expensive, but not outlandish.
>> Superficially, that would be $500bn at the lower cost, but there is likely
>> a 10x or 100x experience curve cost reduction, meaning the whole programme
>> would be about $5-50bn max.
>>
>> As an alternative, you could use aircraft or balloons, but beam
>> attenuation would be a serious issue. 40km balloons can be launched, albeit
>> with small payloads. They would fly at the bottom of the mesosphere, over
>> 99.9pc of the atmosphere. So maybe beam attenuation would be tolerable, at
>> that height. I don't know how to calculate it, but I'm guessing it would be
>> cms to kms - so not really far enough to make a difference to climate. You
>> could perhaps have mountaintop accelerators with very high powers, and a
>> 

Re: [geo] MCB/cirrus stripping with particle accelerators

[Olivier Boucher]

Dear Stephen,

Thank you for pointing this paper, I wasn't aware of it. The PDF is here:
http://orbit.dtu.dk/ws/files/126609957/Svensmark_et_al_2016_Journal_of_Geophysical_Research_Space_Physics.pdf
The paper is from 2016, so obviously couldn't be considered in the IPCC 
AR5. Let's see if AR6 has something else to say.


Svensmark had a similar paper in GRL (2009) which we cite in the AR5:  
"Svensmark et al. (2009) found large global reductions in the aerosol 
Ångström exponent, liquid water path, and cloud cover after large 
Forbush decreases, but these results were not corroborated by other 
studies that found no statistically significant links between the cosmic 
ray flux and clouds at the global scale (Čalogović et al., 2010; Laken 
and Čalogović, 2011). Although some studies found statistically 
significant correlations between the cosmic ray flux and cloudiness at 
the regional scale (Laken et al., 2010; Rohs et al., 2010), these 
correlations were generally weak, cloud changes were small, and the 
results were sensitive to how the Forbush events were selected and 
composited (Kristjánsson et al., 2008; Laken et al., 2009)."


Here I can see the signals are clearer, but still noisy. It would 
probably take an independent study to confirm the findings to convince 
the rest of the community. Also the physical mechanism behind it isn't 
clear. People have tried to increase aerosol nucleation manifold in 
their aerosol models and it doesn't change cloudiness because the system 
is very much buffered in terms of CCN. Pure speculation on my side, but 
I would like to be reassured to hear that there is no difference in how 
the electronics of the satellite instruments respond during Forbusch 
events as compared to the rest of the time.


Thank you again for pointing this, I'll try to discuss it with colleagues.

Best regards,
Olivier

Hi All

I cannot reconcile

https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1002/2016JA022689

with what Olivier says is the IPCC position without saying things 
which might annoy the IPCC.


Can anyone else?

Stephen

On 19-Aug-18 5:48 PM, Andrew Lockley wrote:
As discussed in my original post, a significant scaling of synthetic 
cosmic rays is possible, over background levels (3-5 orders) This may 
give a large climate signal, sufficient to analyse the effect with a 
view to using it for CE.


Does anyone have a view on the potential usefulness of high-volume, 
standard-energy cosmic rays?


A

On Sun, 19 Aug 2018, 16:35 Olivier Boucher, 
> wrote:



Hello Andrew,

see section 7.4.6 of IPCC AR5 :
http://www.ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_Chapter07_FINAL.pdf

The summary is

"Cosmic rays enhance new particle formation in the free
troposphere, but the effect on the concentration of cloud
condensation nuclei is too weak to have any detectable climatic
influence during a solar cycle or over the last century (medium
evidence, high agreement). No robust association between changes
in cosmic rays and cloudiness has been identified. In the event
that such an association existed, a mechanism other than cosmic
ray-induced nucleation of new aerosol particles would be needed
to explain it. {7.4.6}"

Best

Olivier



Cosmic rays cause cloud condensation nuclei. They are therefore
believed to affect cloudiness, and therefore climate. If we made
more cosmic rays, that would likely make it more cloudy. Whether
this was a warming or cooling effect would depend on whether it
was cirrus or cumulus clouds (NB, sometimes making cirrus
ultimately removes water, resulting in less cirrus)

Cosmic rays are almost all protons, with an typical energy peak
distribution of 0.3GEv. (4.8×10^−11  J). No idea if that's the
right energy for CCN, but we can tweak that later.

Creating artificial cosmic rays is possible, using a linear
particle accelerator. This is similar to an ion thruster, as
used in space probes.

To affect climate, you'd probably have to get densities of the
order of 1/s/sqm (more on that, later).

360 million square kilometers of ocean is 360tn sqm or
3.6x10^14sqm. You don't really want to send particles into
people, and the cleaner air over the oceans makes them more
effective.

A kilo of hydrogen contains 6x10^26 protons.

That means 1kg of H2 gives you enough material for 1.6x10^12s =
roughly 50 years - so a satellite could easily carry enough
material to do the job.

Power is 3.6x10^14 x 4.8x10^-11J/s = 17kW - again, well within
what a satellite could muster (roughly 100sqm of solar panels,
at around 20% panel efficiency (conservative) and 50pc
conversion (made up) efficiency).

Cheap satellites are about $50m - well within the capabilities
of a rich philanthropist. Even if this is not cheap, it's still
only perhaps 500m

If I'm out by 5 orders (1 

Re: [geo] Re: MCB/cirrus stripping with particle accelerators

[Olivier Boucher]

You may want to look to 
https://www.geosci-model-dev.net/10/2247/2017/gmd-10-2247-2017.pdf
Sections 2.2.2 and 2.2.3.  There is an associated dataset in netcdf 
format available on the Earth System Federation grid (input4MIPS).
This is a little far from my field, but I trust this is a good source of 
data / information.


Best regards,
Olivier

Thanks, Russell. Do you have a citation for the power numbers for 
natural rays (although I've ignored the rarer, high-energy rays)? The 
numbers you've provided contradict my sources, which are many orders 
of magnitude lower.


For clarity, the comparator technology is an ion thruster, not a 
research particle accelerator. These have to be efficient, otherwise 
they'd impart a very large energy penalty on space probes.


A

On Mon, 20 Aug 2018, 01:55 Russell Seitz, > wrote:


The  grid-to-beam efficiency of  greater than GEV particle
accelerators ranges from kess than 5 % for high current systems ,
to as little as  0.02% for superconducting colliders like the
LHC.  As the global cosmic ray flux is of the order of 5 GW,
matching it might therefore take anywhere from a hundred GW to
several tens of terawatts.

At the high end of that power range one runs into a serious
feedback-  the cloud nucleation cooling might be overwhelmed by
extra CO2  radiative forcing  from the thermal plants in the grid
powering the accelerators.

On Sunday, August 19, 2018 at 10:17:58 AM UTC-4, Andrew Lockley
wrote:

Cosmic rays cause cloud condensation nuclei. They are
therefore believed to affect cloudiness, and therefore
climate. If we made more cosmic rays, that would likely make
it more cloudy. Whether this was a warming or cooling effect
would depend on whether it was cirrus or cumulus clouds (NB,
sometimes making cirrus ultimately removes water, resulting in
less cirrus)

Cosmic rays are almost all protons, with an typical energy
peak distribution of 0.3GEv. (4.8×10^−11  J). No idea if
that's the right energy for CCN, but we can tweak that later.

Creating artificial cosmic rays is possible, using a linear
particle accelerator. This is similar to an ion thruster, as
used in space probes.

To affect climate, you'd probably have to get densities of the
order of 1/s/sqm (more on that, later).

360 million square kilometers of ocean is 360tn sqm or
3.6x10^14sqm. You don't really want to send particles into
people, and the cleaner air over the oceans makes them more
effective.

A kilo of hydrogen contains 6x10^26 protons.

That means 1kg of H2 gives you enough material for 1.6x10^12s
= roughly 50 years - so a satellite could easily carry enough
material to do the job.

Power is 3.6x10^14 x 4.8x10^-11J/s = 17kW - again, well within
what a satellite could muster (roughly 100sqm of solar panels,
at around 20% panel efficiency (conservative) and 50pc
conversion (made up) efficiency).

Cheap satellites are about $50m - well within the capabilities
of a rich philanthropist. Even if this is not cheap, it's
still only perhaps 500m

If I'm out by 5 orders (1 ray per sq cm, not per sq m each
second), then that's only 10,000 satellites. That's expensive,
but not outlandish. Superficially, that would be $500bn at the
lower cost, but there is likely a 10x or 100x experience curve
cost reduction, meaning the whole programme would be about
$5-50bn max.

As an alternative, you could use aircraft or balloons, but
beam attenuation would be a serious issue. 40km balloons can
be launched, albeit with small payloads. They would fly at the
bottom of the mesosphere, over 99.9pc of the atmosphere. So
maybe beam attenuation would be tolerable, at that height. I
don't know how to calculate it, but I'm guessing it would be
cms to kms - so not really far enough to make a difference to
climate. You could perhaps have mountaintop accelerators with
very high powers, and a sweeping beam (like a lighthouse). If
the power requirement was GW-range, then maybe the beam range
would be a hundred km, or so. That might be enough to work,
but it would have some pretty significant effects on local
atmospheric chemistry - so probably not a good idea.

Any thoughts from anyone?

Andrew Lockley


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