Philosophical Vegan Forum

I was thinking about your point on the contrails.

Let's say you buy a seat on a plane and emit 1 tonnes of CO2.
And now say you cause an equivalent warming of 1 tonne of CO2e from contrails.
The contrails last thousands of times less in the atmosphere than the CO2, but trap heat thousands of times more per unit time.
Total 2 tonnes of CO2e.
(This is an oversimplification since there are more than 2 ways planes effect the climate.)

The 1 tonne of CO2 will still be adding to global temperature in 2075 when climate change might be at its worst.
But the contrails are only causing heating now.

Now say the average death rate from climate change this century (2000-2100) is 5 million people per year (500 million people killed by climate change in the century), but in 2021 only 0.5 million people die from climate change. And let's say by 2100 humanity has fixed the climate and regulating it at will.

Does that mean that the contrails although they cause 50% of the warming from a 2021 flight only cause more like 10% of the death and suffering and destruction?

Not completely sure, a bit hard to get your around it, but I think maybe it does mean that? What do you think?

And would that also have been your reasoning for partially discounting it?

I asked a climate scientist and he seems to agree with me.

So contrails may cause 50% of the warming but only a smaller% of the destruction and devastation and suffering and death. The former, the warming, is more measurable, but the latter, even though not really measurable easily, is probably more useful.

This also means that although night flights cause perhaps 2x the warming of day time flights, they may only cause 1.1x or 1.5x the death/suffering/destruction.

Sorry for getting off topic. It only really happened originally because I was linking to an article about food and wanted to explain away the clickbait headline lest it confuse people.

But actually, now I think about Brimstone's Salad's comments, the comparison that bottom trawling and aviation are similar may turn out to be closer to the truth that I thought if we think about harm rather than warming.

Jamie in Chile wrote: ↑Thu Apr 01, 2021 8:49 am I asked a climate scientist and he seems to agree with me.

So contrails may cause 50% of the warming but only a smaller% of the destruction and devastation and suffering and death. The former, the warming, is more measurable, but the latter, even though not really measurable easily, is probably more useful.

This also means that although night flights cause perhaps 2x the warming of day time flights, they may only cause 1.1x or 1.5x the death/suffering/destruction.

That makes sense. 10% seems roughly right, but I think we could be more precise by laying out some scenarios.

For example, let's say we regulate flights in the next 5 years to reduce contrails by 90%, which seems more than plausible based on existing technology and knowledge since it only takes minor altitude changes and changing the timing of flights, and we have solid technology for affordable CCS or the politics to subsidize carbon capture by 2060 (so nothing after that is significant).

So we're talking about being responsible for the share of the industry's 10% contribution between 2026 and 2060 (which we can not claim innocence for since taking flights perpetuates the industry), and responsible for all of the proportionate harm of climate change in the next 5 years (which will be less total harm per year, but a larger share of it).

What % total are contrails? And what kind of prorated damage does that amount to in the next 5 years?
Then after that we could assess the damage of 10% of contrails for the next 39 years.
Add all of that up, divide by years and divide by flights per year, that that's probably what it amounts to per flight.

Does that sound right?



I edited that less/more thing and added a note as you asked.
Also, are you sure about fertilizer vs. manure? What makes you sure that industrially manufactured fertilizer is worse?

I wasn't really thinking of fertilizer vs mature so much as fertilizer vs NO fertilizer.

is there an excess of manure? if it isn't used for this, it's probably just thrown on the ground elsewhere? or does it not work that way?

here's what I read in Bill Gates book

When we add synthetic fertilizer, the ground gets full of nitrogen and it stops the natural process of producing it

to make synthetic fertilizer you produce ammonia which requires heat that we get from burning natural gas

much of the fertilizer applied to soil is wasted and becomes pollution in ground or surface wasters, or escapes into the air as nitrous oxide

That means, if Bill Gates is right here, synthetic fertilizer produces all three of the world's top greenhouse gases. Carbon dioxide from burning the natural gas, the nitrous oxide and "natural gas" I think usually means mostly/entirely methane so that would just be the leakage.

He says fertilizer are 1.3 billion tons of greenhouse gas emissions in 2010, if he means CO2e that's over 2% of the global warming. If he means actual weight I think it would be even worse.

I am a little confused on your contrails post. Does the "10% seems roughly right" refer back to the 1.1x of the "may only cause 1.1x or 1.5x the death/suffering/destruction". i.e. 1.1x = +10%?

And when you later in your post refer to 10% again, this time in the phrase "industry's 10% contribution" is this the 10% remaining after you've deducted the 90% above. In which case, we have two different 10%s, not referring to the same thing?

I don't think we are going to regulate contrails in the next 5 years. You would have to ask yourself where the political will would suddenly come from. There is very little political will on aviation for now, there is some around transport and electricity. So I don't think that will suddenly happen.

Jamie in Chile wrote: ↑Thu Apr 01, 2021 8:56 pm I wasn't really thinking of fertilizer vs mature so much as fertilizer vs NO fertilizer.

Even if we are talking about nitrogen fixation by plants, that's not necessarily benign on it's own either when it comes to nitrous oxide, it does release some greenhouse gases. The best you can do is try to regulate the nitrogen in the soil to what's actually needed and *when* it's needed. Plants only need a large amount of nitrogen at certain points that farmers have identified, which means with synthetic fertilizers this can be targeted better to when it's needed leaving lower levels the rest of the time.

Jamie in Chile wrote: ↑Thu Apr 01, 2021 8:56 pmis there an excess of manure? if it isn't used for this, it's probably just thrown on the ground elsewhere? or does it not work that way?

If not used on the ground they have a disposal problem, but that's a problem we want the industry to have as a tax on its profits impeding growth. Buying steer manure not only saves them money but puts money into the industry's pockets subsidizing the industry as a whole -- which means more cows on the pasture or in feed lots producing more methane, and more energy wasted on feed.

Jamie in Chile wrote: ↑Thu Apr 01, 2021 8:56 pmhere's what I read in Bill Gates book

When we add synthetic fertilizer, the ground gets full of nitrogen and it stops the natural process of producing it

That is untrue/only sometimes true. When it comes to the soil itself, that's pretty much false because the nitrogen added isn't going to affect free nitrogen fixing bacteria's metabolism. When it comes to plants with nitrogen fixation in the roots, there are different kinds of nitrogen fixers, some downregulate production of nitrogen depending on the balance in the soil while others do not, and I think it lies more along a spectrum. It's a mixed bag, because those that downregulate are pretty climate neutral but they only provide nitrogen for themselves and don't benefit other plants much if any at all, those that do not down downregulate may release more nitrogen for other plants but also pose their own climate problem if that nitrogen is not all used up.

Ultimately, however, free nitrogen is free nitrogen. If you're dealing with a plant that doesn't significantly fix its own nitrogen then it needs free nitrogen in the soil and it doesn't matter where it's coming from. As I mentioned before, however, free nitrogen applied from synthetic fertilizers provides a more targeted and immediate supply which can mean less free nitrogen to be converted into greenhouse gases the rest of the time when no longer needed.

A lot of noise is made about the slow release nitrogen in manures, but this is not necessarily an advantage.

Jamie in Chile wrote: ↑Thu Apr 01, 2021 8:56 pmmuch of the fertilizer applied to soil is wasted and becomes pollution in ground or surface wasters, or escapes into the air as nitrous oxide

True of any free nitrogens. Likely the only real winners are legumes which don't require fertilization because they are fixing their own nitrogen.
If we do genetically engineer other plants to fix their own nitrogen that might be pretty big.

Jamie in Chile wrote: ↑Thu Apr 01, 2021 9:19 pm I am a little confused on your contrails post. Does the "10% seems roughly right" refer back to the 1.1x of the "may only cause 1.1x or 1.5x the death/suffering/destruction". i.e. 1.1x = +10%?

Yes, the additional 10% attributable to the contrails. I assumed you meant the 1 was the CO2, which isn't plausibly ameliorated by regulation. There's no practical CCS for airplanes and they can't plausibly go electric due to weight.
We could move to hydrogen fuel for airplanes and do CCS on the ground when it's cracked. That's something that might happen, but seems less likely than for other industries because it needs more changes to take place. The main thing airlines can change is contrail production.

Jamie in Chile wrote: ↑Thu Apr 01, 2021 9:19 pmAnd when you later in your post refer to 10% again, this time in the phrase "industry's 10% contribution" is this the 10% remaining after you've deducted the 90% above. In which case, we have two different 10%s, not referring to the same thing?

I don't follow.

Jamie in Chile wrote: ↑Thu Apr 01, 2021 9:19 pmI don't think we are going to regulate contrails in the next 5 years. You would have to ask yourself where the political will would suddenly come from. There is very little political will on aviation for now, there is some around transport and electricity. So I don't think that will suddenly happen.

Political will on global warming is growing, as is awareness that flights are a problem. Contrails is a very easy target because they're so easy to avoid using modern technology and small changes, including something like a cap and trade system to incentivize formation of early morning contrails to reflect light rather than trap in heat in the evening: https://catsr.vse.gmu.edu/Contrails.htm
The main thing is that it doesn't sacrifice people's ability to travel the world, so it's pretty painless, and it doesn't necessarily cost airlines profits either (which I think would eliminate the political will).
I think five years is a plausible time line to see regulation on contrails. I don't think it'll happen this term in the U.S., but maybe next one.
That first big study that got press attention was only 2019 after all

So do you think inorganic vs organic is secondary to the question of using the right amount and avoiding too much (in debate relating to nitrogen and climate change)?

If the manure is being purchased from a factory farm operation, then I would agree that it’s making tht operation more profitable and thus causing more animal suffering and death. If it’s being given away, then it probably doesn’t matter much (assuming that the avoided cost of disposal is very low). I think this is key. Do you know which approach is more common?

I may have added all I can on this aspect of the debate.

Jamie in Chile wrote: ↑Sun Apr 04, 2021 2:26 pm So do you think inorganic vs organic is secondary to the question of using the right amount and avoiding too much (in debate relating to nitrogen and climate change)?

The optimal is probably a small amount of organic fertilizer from green manure (like composted clover) for the slow release baseline, then inorganic fertilizer for boost in free nitrogen only at the appropriate time.
In my understanding, organic fertilizer can never beat synthetic in terms of immediate nitrogen.

In terms of animal manure, I'm not sure if there's any good way to avoid the methane production from its anaerobic decomposition since it tends to be very wet (slurry) or dense. Compost is more "fluffy" and seems to permit more oxygen penetration. Manure is also starting with a large amount of anaerobic microbial inoculation. You can compost manure, but I think it would need to be high carbon or have a lot of other matter added to be successful.

Jamie in Chile wrote: ↑Sun Apr 04, 2021 2:26 pm If the manure is being purchased from a factory farm operation, then I would agree that it’s making tht operation more profitable and thus causing more animal suffering and death. If it’s being given away, then it probably doesn’t matter much (assuming that the avoided cost of disposal is very low). I think this is key. Do you know which approach is more common?

I mean, even free beats trying to pay for disposal. That wouldn't be cheap. I don't know the average, but I've seen articles talking about it being expensive to have manure hauled off so it's important to advertise locally to try to give it away instead.

I think "can't possibly go electric due to weight" is overstating it. I think I would go with "direct, long-haul flights almost certainly can't go electric because of weight unless there is an unlikely technological breakthrough".

I believe routes such as London-Paris, New York-Washington, San Francisco-Los Angeles probably can be electrified and powered with low carbon energy. With enough political will, you could see this in the 2030s, at least in theory. There are lots of emissions from short haul flights because routes like that often have multiple flights per day per airlines, vs one per day per airline on most long haul routes.

In theory, I also see no reason why you couldn't fly mid haul distances as well by landing the plane a few times on the way in order to swop out batteries, recharge the batteries or have passengers change to an identical plane parked next to the first one that just landed. This would be better than catastrophic climate change and faster and easier than overland or boat travel for such distances.

But, in practice, the industry seems to have moved away from electric in the last 2-3 years and seems to be leaning more towards hydrogen and electrofuels. I wonder if this is because electric for short and mid haul requires huge redesign of planes and the business model, whereas hydrogen and electrofuels are closer to a drop in replacement fuel.

Unfortunately, hydrogen (from electrolysis and CCS) and electrofuels (that produce CO2 in flight but also start off with CO2 and so can be carbon neutral in theory) are both expensive.

I think we need to have a very high carbon tax on flights - and everything else- and the public should accept it because if the funds raise are dividended back to the people equally most people win since the majority of the flights are taken by the rich (I am a supporter of "fee and dividend").

Clearly this would lead to a reduction in flights and there is no political will for this at the moment but I think one day something has to change.