Make Sunsets: Clarifications!

[Luke Iseman]

Thanks Andrew, Olivier, Bala, and everyone else for diving in with critiques here. I'm a cofounder of Make Sunsets and want to clarify a few things: 

Honesty: 

We have no desire to mislead anyone. If we make a mistake (which we will), we'll correct it. 

Radiative Forcing:

I didn't make this "gram offsets a ton" number up. It comes from David Keith's research:

"a gram of aerosol in the stratosphere, delivered perhaps by high-flying jets, could offset the warming effect of a ton of carbon dioxide, a factor of 1 million to 1."

and, again: "Geoengineering’s leverage is very high—one gram of particles in the stratosphere prevents the warming caused by a ton of carbon dioxide."

By stating "offsetting the warming effect of 1 ton of carbon for 1 year," I was trying to be more conservative than Professor Keith. I am correcting "carbon" to read "carbon dioxide" on the cooling credit description right now, and I'm adding a paragraph at the start of the post stating that estimates vary, but a leading researcher cites a gram offsetting a ton. 

For the several hundred dollars of cooling credits we've already sold, I'll be providing evidence to each purchaser that I've delivered at least 2 grams per cooling credit. 

Olivier, or anyone else: I'd be happy to post something by you to our blog explaining what you estimate the radiative forcing of 1g so2 released at 20km altitude from in or near the tropics will be and why. I will include language of your choosing explaining that you in no way endorse what we are doing.

I very much hope to get suggestions from this community on instrumentation we should fly to improve the state of the science here. Again, I'm happy to do this with disclaimers about how researchers we fly things for are not endorsing our efforts. Or even without revealing who the researchers are: we'll fly test instruments and provide data, no questions asked:)

Telemetry: 

My first 2 flights had no telemetry: in April, this was still in self-funded science project territory. After burning some sulfur and capturing the resultant gas, I placed this in a balloon. I then added helium, underinflating the balloon substantially, and let it go. There is technically a slim possibility that neither of these balloons reached the stratosphere, as I acknowledged to the Technology Review reporter. I will add Spot trackers to my next flights. These cut out at 18km, so I'l be able to confirm that I achieve at least this altitude. If (and this is a big if) I'm able to recover the balloons, I'll have a lot more data from the flight computer. I will eventually switch to Swarms, which should let me transmit more data regardless of balloon recovery.

Pricing: 

Bala, you're totally right that this should be priced much lower. We're trying to make enough with our early flights to stay in business until we get meaningful traction with customers, and we plan to eventually drop prices to $1 per ton or less.

Reuse: 

We are not yet reusing balloons, and Andrew is correct that latex UV degradation will limit our ability to do so with weather balloons. Given that balloon cost is our main expense per gram, even a few uses per balloon will dramatically improve the economics here.

I expect to disagree with some of you, but I hope we can do so politely and assuming good intentions.

[Daniele Visioni]

Luke,

I will keep finding this rather murky as long as you keep being so hand-wavy about your numbers and then claiming you can offset a “substantial amount of warming” in your homepage.

Weather balloons have different bursting altitudes depending on 1) payload 2) amount of helium used to inflate 3) material.

You can find an example here with a calculator down below that lets you calculate max bursting height based on inflation

 https://www.highaltitudescience.com/products/near-space-balloon-1200-g

Which balloons did you use?

How much did you inflate them?

Did you check with the producer if the mix of SO₂ and He in the balloon would affect their calculations, and if so how?

The forcing we’re talking about changes depending on altitude of release as well: at 19 it’s different than at 25 (and depending on your definition, sometimes the tropopause is above 18km..), and above 29km sulfate aerosols evaporate because temperatures are too high to form liquid aerosols. If the balloon doesn’t burst at the right altitude, what would happen to the oxidized S is not so simple - frankly I don’t know the answer off the top of my head, there are a few factors that could influence this. Do you have studies showing what would happen there based on lack of water vapor and different temperature and OH levels?

If you don’t - and you don’t have any tools to measure it yet - maybe you should at least tone down the claims already present on your website?

For some ranges of stratospheric releases of sulfate we have some numbers for SAI we can be somewhat confident about - not just in term of the forcing but in terms of downstream effects on the stratospheric composition - but this may not be true for what you are proposing or claiming you are doing.

Lastly, in your Twitter account you claimed in a post 2 days ago that there are “supporters and scientists who believe in you”.  I would avoid claiming you have the support of scientists if you don’t - or show proofs if you do.  As far as any scientist I know is concerned they don’t seem particularly impressed - and your lack of clarity goes against any of the calls for open and transparent research (not to mention inclusive decision making) this community has asked in previous public statements.

Daniele 

On 28 Dec 2022, at 18:09, Luke Iseman <lu...@lukeiseman.com> wrote:



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[Andrew Lockley]

Luke, you should also be aware of criticisms of short term CDR climate intervention, eg by Höglund. He explained his arguments to Reviewer 2 https://open.spotify.com/episode/792ZqIXDuqTOVdoJE3ZNyu?si=mTUC3aQdS_yJqISL7H0rXw

He strongly criticises vertical stacking, arguing that short term interventions are useless or harmful unless sustained.

There is a substantial literature on termination shock, which raises similar issues re SRM 

Due to the cancel culture and unchecked bullying in academia, I do not express any opinions in public, outside of the published literature. However, you may be interested in 2 papers I wrote on private and state customers for commercial SRM, which I will naturally refrain from summarising. 

Licence to chill (private buyers) 

https://www.academia.edu/23166474/Licence_to_chill_Building_a_legitimate_authorisation_process_for_commercial_SRM_operations

State Commissioning of Solar Radiation Management Geoengineering

https://www.tandfonline.com/doi/full/10.1080/21550085.2020.1848176

Andrew Lockley 

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[Russell Seitz]

Luke:

In the stratospheric balloon  releases you have so far described, how many grams of helium are required to loft one gram of SO2?

[Stephen Salter]

Hi

I do not understand the bit about bursting. Control of a venting valve protects the balloon and allows release at the chosen altitude.

Helium is irreplaceable and needed for super cooling. Is there a reason not to use hydrogen?

Stephen

 

Emeritus Professor of Engineering Design

School of Engineering

University of Edinburgh

Mayfield Road

Edinburgh EH9 3DW

Scotland

0131 650 5704 or 0131 662 1180

YouTube Jamie Taylor Power for Change

 

 

 

From: geoengi...@googlegroups.com <geoengi...@googlegroups.com> On Behalf Of Daniele Visioni
Sent: 28 December 2022 23:51
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Cc: geoengineering <geoengi...@googlegroups.com>
Subject: Re: [geo] Make Sunsets: Clarifications!

 

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[Andrew Lockley]

Large weather balloons don't have much over pressure relative to volume, so venting is a challenge. Valves and pumps add weight. Hydrogen has ground handling risks, due to flammability (Hindenberg), and any leaks risk buoyancy loss and the canopy descending loaded. The most extreme scenario is that an out of control failed balloon descends into an enclosed building through an open door, skylight, or Courtyard. In windy conditions, drift into a small industrial unit is perfectly possible, through the roller shutter doors - which could be automatically or accidentally closed behind, trapping the balloon and its flammable payload. This could allow a loaded canopy to leak out into a fully enclosed space, with ignition risks.

While such scenarios appear outlandish, with thousands or millions of launches, they become real risks.

Andrew 

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[Hawkins, David]

Your web site claim that 1 gram of SO2 injected offsets the effect of 1 ton CO2 for a year is fundamentally misleading.  Any effect on temperature of injected particles lasts only as long as the particles are in the stratosphere.  If a one-time injection has a lifetime of 1-2 years that injection addresses the impact of a one-time release of a ton of CO2 for only a small fraction of its lifetime.  Even if the rest of your numbers are right, to address the warming impact of 1 ton of CO2, you would need to continue your releases for hundreds of years.  A one-time release is meaningless is addressing the climate impacts of CO2.

David

Sent from my iPad

On Dec 28, 2022, at 6:09 PM, Luke Iseman <lu...@lukeiseman.com> wrote:



--

[Alan Gadian]

Andrew,

I used Hydrogen for 20 years to use for weather balloons.  No problem , even when one exploded fir a colleague in a balloon shed ( he has the doors firmly closed and there was a leak , which he knew about). Probably millions of radiosondes were launched with hydrogen. We had a fusion lab where hydrogen was piped around the facility.  However, in the Falklands they had a hydrogen making device … ( solid + water).  Now that was dangerous.   There was one hole in the ground in africa where a hydrogen plant as above had been sited, but using the stuff is a safe.  

obviously , if you plant a bomb nearby , little is safe ( what was the actual cause of the hind disaster?) 

i predict trains / trucks / cars will soon be using the stuff. Far greener than Li batteries and I think safer.  Never mind the Co2 output.  An electric car costs more to produce as regards Co2 than a small petrol car does ( + 70,000) miles of petrol.  i should have bought an H2 car, but the problem is there are / were on 11 charging stations in the YK and 8 of them were in the M25

A. 

T ---

Alan Gadian, UK.

Tel: +44 / 0  775 451 9009 

T ---

On 29 Dec 2022, at 11:05, Andrew Lockley <andrew....@gmail.com> wrote:



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[Stephen Salter]

Andrew

The survival rate for the Hindenburg was much higher than for aircraft fuelled with kerosene because its lightness means it leaks upwards. Heavy vapours like propane or butane are very much more dangerous if they sink into cellars or bilges. The hydrogen flame has a very low emissivity. No pump is needed. I can give you a valve design weighing less than one gram. Think open prairie for launching.

Stephen

[Daniele Visioni]

Folks, while you are giving free ideas to these people (not necessarily good ones - please go take a look at recent research about hydrogen GWP and impact on stratospheric compostion https://acp.copernicus.org/articles/22/9349/2022/) you might want to be aware that at the first hint of questions on this mailing list and on Twitter they quickly switched from “we’ll openly publish all our data” to “gives us 10k to know just the brand of the balloons we’re using” https://twitter.com/makesunsets/status/1608513289247686657?s=46&t=m_d3Xnwl0uI3AfdgdF-nZg

(The balloons that were claimed to be reusable and suddenly aren’t)

which I would say should clarify all we need to know and perhaps stop engaging with them in good faith?

A reminder that what this community is trying to claim first and foremost is how fundamental total transparency is in this field to build trust. 

Daniele 

On 29 Dec 2022, at 07:16, Stephen Salter <s.sa...@ed.ac.uk> wrote:



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[Andrew Song]

Hi Daniele,

I'm the other co-founder of Make Sunsets, I was the one that wrote that post. Apologies I misspoke and the tweet has been deleted. We plan on releasing balloon spec soon. Thank you for your concern, we will do better next time.

Best regards,
Andrew Song
Co-Founder of Make Sunsets

[Andrew Lockley]

Stephen,

I hope you can share your calculations or experimental data to show the performance of a valve vented balloon at realistic over pressure. 

Risks for hot landings have to be multiplied by the number of flights - which would surely need to be in the millions to influence global climate to detectable levels. Balloons ending up in barns and workshops is a possibility. 

Andrew 

[Russell Seitz]

Luke,  Make Sunsets has tweeted invoking "trade secrets ' in denying simple requests to quantify how much  helium is needed  per

 " cooling credit".

This lack of transparency cannot stop anyone , policy analysts included from running the numbers .

Dimensional analysis  based on handbook  and commercially disclosed values of the physical constants of  air, helium and SO2 indicates that you can at best hope to lift 1.01 Kg per  STP cubic meter of 97% pure balloon grade He. 

Since SO2 vapor's molecular weight makes it over twice as dense as air  ( ~64/29),  even if  if the dead weigh of the balloon and its telemetry are completely disregarded it will still take  a tonne  or more of helium to loft a  tonne of aerosol feedstock to stratospheric elevation.

As you must be aware,  the short supply of helium ( the US strategic reserve acquired after WWII was largely sold off by 2021)  has already quadrupled its cost.,  and at present , annual   global production is below100,000 tonnes and recoverable reserves stand at around 30 million tonnes globally. 

Using NOAA's numbers:

https://research.noaa.gov/article/ArtMID/587/ArticleID/2756/Simulated-geoengineering-evaluation-cooler-planet-but-with-side-effects

 it is clear that your scheme would  require lofting of a megatonne  or more of SO2 a year per degree K of cooling: which is not only an order of magnitude more that present production can bear, but enough to completely deplete known reserves and resources by 2050. 

Finally, US helium is almost exclusively a byproduct of natural gas production , and so entails substantial release of  methane and other hydrocarbons that are greenhouse gases  more powerful than CO2

On Wednesday, December 28, 2022 at 6:09:51 PM UTC-5 lu...@lukeiseman.com wrote:

[Josh Horton]

I want to repeat a set of questions I publicly posed to Luke on December 9, few if any of which have been fully answered (despite the statement "Happy to answer any questions").

Hi Luke,

Can you provide more information about your launches--locations, flight descriptions, release altitudes and amounts, safety protocols, consultations, permits, funding, etc.?

Josh Horton

[Luke Iseman]

Josh, 

I believe I've addressed all of these I can. You'll get a lot more detail when I fly telemetry, particularly if I can recover the balloons after the flight. To recap:

locations: Baja California

flight descriptions: the balloons were intentionally underinflated and went up. guesstimate 25-30km burst altitude. as i have made clear, i cannot confirm with 100% certainty that they reached the stratosphere.

release altitudes and amounts: don't know, several grams

safety protocols, consultations, permits, funding, etc.? nothing to add here that hasn't been covered.

These were self-funded, initial flights. They were meant to demonstrate (mainly to me) that I could launch balloons containing some small amount of sulfur dioxide. 

--------------------

Luke Iseman

make sunsets : global cooling

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[Joshua Horton]

Setting aside whether answers like "don't know, several grams" are sufficient in this context, I don't recall seeing anything about safety protocols, consultations, or permits.  Did you talk to Mexican authorities before doing this?

Josh

On Fri, Dec 30, 2022 at 10:39 AM Luke Iseman <lu...@makesunsets.com> wrote:

Josh, 

I believe I've addressed all of these I can. You'll get a lot more detail when I fly telemetry, particularly if I can recover the balloons after the flight. To recap:

locations: Baja California

flight descriptions: the balloons were intentionally underinflated and went up. guesstimate 25-30km burst altitude. as i have made clear, i cannot confirm with 100% certainty that they reached the stratosphere.

release altitudes and amounts: don't know, several grams

safety protocols, consultations, permits, funding, etc.? nothing to add here that hasn't been covered.

These were self-funded, initial flights. They were meant to demonstrate (mainly to me) that I could launch balloons containing some small amount of sulfur dioxide. 

--------------------

Luke Iseman

make sunsets : global cooling

On Fri, Dec 30, 2022 at 8:03 AM Josh Horton <joshuah...@gmail.com> wrote:

--

[Luke Iseman]

Russell, 

My cofounder tweeted the "trade secrets" claim in error (see further up in this thread). 

I agree helium is a valuable resource and intend to switch to hydrogen in the future. 

I also don't have religion around balloons: if anyone has a surplus stratospheric aircraft sitting around along with a venue from which to fly it, that's probably a better value then balloons;)

--------------------
Luke Iseman

lukeiseman.com

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[Joshua Horton]

And why not just do this in the US?  That's where you're based, correct?

[Daniele Visioni]

Aside from simply being a greenhouse gas (and not to mention how it is produced - countries use weather balloons filled with hydrogen but the machinery to produce H on site is expensive, and the handling procedures are complex, see https://www.fp2fire.com/hydrogen-balloon-inflation/), hydrogen is a reactive species that tends to deplete hydroxyl radical molecules (forming H2O), which also happens to be what you need to produce H2SO4.

So if you started using hydrogen you would:

- have even more and possibly unknown reaction capable of modifying ozone (meaning the link to our study on ozone depletion you have on your website would be irrelevant), and potentially rendering your SO4 formation processes inefficient 

- risk balloon safety - normally you need to make sure you’re only putting H in your balloon (see link above). I doubt balloons have been tested with such a mixture inside, and that some form of reaction wouldn’t occur.

- assuming you use 1g of H for 1g of sulfate, as Russell has already said, at scale you would emit in the stratosphere a quantity of hydrogen similar to current estimates for the whole hydrogen leak rate of a whole hydrogen economy in 2050 (source https://www.energypolicy.columbia.edu/research/commentary/hydrogen-leakage-potential-risk-hydrogen-economy#:~:text=The%20leakage%20rate%20stands%20between,%242%2Fkg%2DH2).

But if that hydrogen was released in the stratosphere directly its GWP would be much higher than that estimated from current surface leaks (https://acp.copernicus.org/articles/22/9349/2022/) 

So while doing stunts with Helium and sulfate you produce yourself may be seen as potentially harmless, without proper studies doing the same with hydrogen would be outright insane and hazardous. 

Onus would be on you to prove otherwise before outdoor tests.

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[Andrew Lockley]

Dan

What's your view on using CH4 as a lifting gas at volume scale? 

Andrew 

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[Russell Seitz]

Thanks for the link to the Ocko & Hamburg paper.  Steve and I often disagree , but in terms of the numbers we're on the same page on this one.

Luke gets points for facing reality on the  helium supply situation, but  his retreat into the arms of hydrogen and heavier than aircraft makes me wonder if his marketing people haven't missed the boat 

As  balloon payload ratios improve with envelope size, and the metal is remarkably resistant to sulfuric acid corrosion , one large scale SO2 delivery vehicle  is the most attractive by far.  

I'd contribute  ten dollars to a  lead zeppelin revival.

[Andrew Lockley]

This useful dialogue helps repair the communication breakdown, ensuring we can all stay friends - that's the way it should be (my desire, anyway).

I've been wondering when the levee breaks for some time, on test deployment. Balloons seem to be the epic small scale approach, considering there's no stairway to heaven. But not a whole lotta love has been expressed for the idea, leaving me dazed and confused - but I hope, in our enthusiasm for scrutiny we don't leave Luke and Josh trampled underfoot, behaviour we should give no quarter to. 

I wonder if they might consider Kashmir for their next launch, which is on a similar latitude, but with no risk of flying over the ocean, since recovery is difficult any further than down by the seaside - although they might have difficulty going to California afterwards. But calls for an American launch for jurisdiction reasons - some kind of LA drone, seem to be very US centric. How many more times will this perspective be repeated? 

We can look forward to Luke doing telemetry launches, allowing tracking over the hills and far away. 

Right, I'll end this before I start to ramble on. The unusual tone of this email is nobody's fault but mine. 

All my love

Thank you 

Andrew

PS luke - something else before I go - was it a night flight, or in the evening, which would reduce UV damage to the canopy?

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[Russell Seitz]

When I was at MIT, "War Surplus " stores abounded in $5 canned hydrogen  generators designed to fill radiosonde or  life raft rescue balloons. The gizmo opened with a can of sardines key  to expose  the calcium hydride within to sea water, and  filled  the attached 1- meter balloon in about 15 minutes. 

Whereupon, it being sunset on the 4th of July on an easterly beach with a westerly wind, we attached a slow  magnesium ribbon fuse and let it go . it traveled some miles downwind  and rose perhaps one before exploding with a pale flash, but no audible pop

The current  low cost balloon record seems to be held by   the 22 meter Le Ballon Air de Paris,  filled with 6,000 m3 (210,000 cu ft) of helium and  terthered with a cable winch.  It can board up to 30  tourists, max  total weigh 2,500 kg (5,500 lb) whom it takes to  150 m (490 ft) above Paris.  for 15 minuteas a apsesent fare of sixteen Euros a head.

Though hardly stratospherics, that works out to $194  a tonne 

[Chris Vivian]

Edward Parson has posted a commentary on Legal Planet about the Make Sunsets concept - see - A Dangerous Disruption - Legal Planet (legal-planet.org)   

Chris.

[Russell Seitz]

Has Andrew Lockley  been punked along with James Temple?

Legal Planet ' s sober fisking of Make Sunsets failed to notice its executives most interesting potential  liability defense —   the  ChatGPT AI did it !

 Iseman & Song's  offering website ran the following  

Author's note: 99% of this blog post and title was written using the help of ChatGPT and the hero image was generated using DreamStudio. The title was generated based off the content of the blog post.

[Andrew Lockley]

Could you please clarify how you think I've been "punked"? I interviewed the founders for 2h, they weren't chatbots. https://open.spotify.com/episode/2Fr15fdX20qyyfVX8VCF3Q?si=5Hq3ikM2QS6MVilqYvPZig

I don't think using AI to create content is irresponsible, provided it's checked for accuracy. 

Andrew 

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[Russell Seitz]

Technically, there's no there there,  and their podcast performance makes one doubt the intellectual seriousness of their investors 

As a matter of due diligence , have you contacted  the VC's whose allegiance Make Sunsets claims ?

[Andrew Lockley]

I don't understand your first question. And no, Reviewer 2 doesn't do any background research / verification. It would be dumb to lie about it. 

Andrew 

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[Oliver Morton]

As Russell points out, helium is far too valuable to be used for this. As Daniele points out, hydrogen does chemistry with alacrtity -- and thus at very least wets the stratosphere to a degree which would seem disturbing. In suggesting methane i think Andrew has chosen...poorly.

And Josh has his finger on something absolutely crucial. As someone with an interest in developing-country solar geoengineering research via my relationship with Degrees, I think doing this work in Mexico without seeking to involve Mexican researchers or investigation of permitting is completely indefensible. As far as I can see, Luke has not provided an account for why the flights were launched from Mexico rather than the US, and in the absence of such an account it is very hard not to see this as developed world actors choosing a developing country venue for nefarious reasons. 

best, o

[Russell Seitz]

If Oliver's book has anything to teach it is that environmental entrepreneurs,  amateur and professional, have yet to discover any real limits to the credulity of their investors.  

This one seems to fall somewhere between  space mirrors and Ice 911, but  the sky's the limit in the vaporware market :

 Having already found  some inspiration in  the tequila sunsets of Baja California, perhaps they should focus their  considerable powers of speculation on Hawaiian punch:

https://vvattsupwiththat.blogspot.com/2023/01/the-next-big-thing-in-tequila-sunsets.html

[Andrew Lockley]

I think they mentioned somewhere it was due to latitude. I didn't have time to ask them much about injection pattern in the Reviewer 2 interview. https://open.spotify.com/episode/2Fr15fdX20qyyfVX8VCF3Q?si=KMEg9KvIRFiuoTcwYUp2OQ

Andrew 

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[Luke Iseman]

Again: can we please not assume I'm an evil AI hoax?? 

In spite of having been born in the U.S., I spend 4+ months per year in Baja and intend to be based here as much as I can. I bought land here over a year before contemplating starting Make Sunsets. The nefarious reason to launch from here is that I love it and happened to already have a place here.

Oliver: as "someone with an interest in developing-country solar geoengineering research," please consider researching where to launch from for maximal cooling effect. I want to launch in/near the tropics for greater cooling per gram via increased particle residence time (another source).

I agree that we should prioritize the voices of those in the developing world, and I dream of growing Make Sunsets to where it can provide meaningful economic opportunities to some residents of island nations whose very existence is threatened by climate change.

Personally, I find it "completely indefensible" to place the onus on those most harmed by climate change to initiate work on measures to buy us more time. 

--------------------

Luke Iseman

make sunsets : global cooling

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[Florian Rabitz]

To add two points to this discussion.

First, there are some serious flaws with solar geoengineering offsets analogous to carbon offsets. This isn't only because of the broader problem of public trust with any commercial use of SG. It's also because carbon markets are designed for removals that are permanent at human time-scales; and because there is some scope for market demand to fluctuate. SG offset markets simply do not make sense because what if there is a sudden drop (or spike) in demand? This certainly doesn't matter if you are releasing a few grams or kilograms in total, but at a larger scale, you would need some rather complex reserve-banking system to avoid termination shock if demand crashes. So let's face it, these credits are simply a gimmick for making money from gullible investors.

Second, many people have, for years, tried to steer a cautious and somewhat even-handed course through what you are all aware is an incredibly polarized public debate. Discussing geoengineering in a balanced and civilized manner is difficult enough as it is, without dubious start-up entrepreneurs doing who-knows-what because they recently read a novel by Neal Stephenson. I feel this is really counterproductive and undercuts the efforts of all those that have been trying to build public trust and engagement for informed and high-quality future decision-making. This little adventure isn't going to help with anything and we all know the potential political ramifications.

Just my 2 cents,

Florian