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Air Travel Emissions Vastly Outpace Predictions

nytimes.com

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Re: Air Travel Emissions Vastly Outpace Predictions

#261

Post by lutorm »

martamoreno2 wrote: post #8

2.5% eh? We should all immediately stop flying... This is outrageous. Just imagine, 2.5%!! But on a more serious note, this article is again wrong, like so many others about climate change. Being a combination of clickbait and false assumptions, it fails to miss the point entirely that first, 2.5% are irrelevant, but also that it makes no sense whatsoever to tackle this now. The technology is just not there yet. What…

Given that switching to renewable energy is already becoming cost-competitive with fossil fuels, while CCS is a pure cost, what makes you think a major investment in CCS is more likely than reducing emissions in the first place?

Re: Air Travel Emissions Vastly Outpace Predictions

#262

Post by learnstats2 »

TulliusCicero wrote: post #239
js8 wrote: post #223

Earlier quoted context omitted.

> A world with greatly reduced air travel is a more insular and less understanding world. I don't think there is an evidence for that. It is more likely that immigration increases cultural understanding rather than travel. In any case, emissions of travel can be greatly reduced by using other modes of transport and by making the stay in the target country longer. Such a cultural shift could actually even improve the…

> I don't think there is an evidence for that. It is more likely that immigration increases cultural understanding rather than travel. Disagree that travel doesn't matter, but even then, do you really think it being much harder to visit their home countries again will have no impact on immigration patterns? > In any case, emissions of travel can be greatly reduced by using other modes of transport Would love to hear…

> Disagree that travel doesn't matter

We know - you already made this point in the parent comment.

> sans airplanes

You've moved the goalposts from 'greatly reduced air travel' to 'sans airplanes'.

Re: Air Travel Emissions Vastly Outpace Predictions

#263

Post by ac29 »

snowwrestler wrote: post #222
loeg wrote: post #150

Earlier quoted context omitted.

(And little substitute for burning hydrocarbons as airplane propellant. Energy density and stuff like fire safety really really matters in aviation.) Totally agree that air travel is one of the last places to look for carbon savings. That said, carbon offset taxes should be applied where they are not already. The market can price this cost in and judge whether the value is there, if the incentives are structured corr…

An area of research that I don't hear much about is creating hydrocarbon fuels for applications that really need them, like airplanes. Essentially, using hydrocarbons as a chemical battery instead of an out-of-the-ground energy source. As with any contributor to climate change, the issue is not burning the fuel, the issue is that the fuel is bringing new carbon out of the ground into today's carbon cycle. Hydrocarbon…

Biofuels are certainly a thing - over 100 billion liters were produced last year [0]. For a while, it looked like there were credible avenues to using algae to produce jet fuel, and there were even test flights. Unfortunately, pumping fuel out of the ground is really, really cheap, and most of these companies went under or pivoted [1] (a gallon of algae-produced omega-3 oil or cooking oil is worth far more than a gallon of algae-produced Jet-A).

[0] https://en.wikipedia.org/wiki/Biofuel

[1] https://www.greentechmedia.com/articles/read/lessons-from-th...

Re: Air Travel Emissions Vastly Outpace Predictions

#264

Post by dredmorbius »

vonmoltke wrote: post #234
dredmorbius wrote: post #181

Earlier quoted context omitted.

Aircraft use a lot of fuel. Roughly half the takeoff weight of an airliner is fuel. The fuel burned on a continental-distance (3000+ km / 2000+ mile) flight is roughly equal to the passenger's weight. CO2 emissions by mass exceed the mass of the fuel by a factor of three , as you're adding the mass of the oxygen that's added, far more than the hydrogen that's split off. https://www.engineeringtoolbox.com/co2-emission…

> At Shanghai-NYC distances, that's 34,300 kg of fuel That's sounds very low for fuel burn at that distance for a 747. The 747-8 carries over 191,000kg of fuel, yet has a maximum range of only 14,320km. As an aside, I wonder if using "carbon" as shorthand for "carbon dioxide" does more harm than good.

I've updated my comment to make clear that's a back-of-the-envelope calculation, and not based on actual performance data. Generally, if you're within a few powers of two with the approach, it's a good start, and empirical data trump rough estimates any day.

The "carbon" vs. "fuel" vs. "CO2 emissions" terminology is legitimate -- these are all different real aspects of the phenomenon. Playing fast and loose between these, or simply confusing the terms (see also kW vs. kWh confusion in energy discussions) is far too common. I specifically called which of these I was using and how they're related.

Much of this would benefit by more use of tables and graphs and sensible comparisons, so that people are at least familiar with appearances. Understanding might or might not follow, but the journalistic practice of "tell a story around numbers without using numbers or pictures" seems to me actively harmful.

Re: Air Travel Emissions Vastly Outpace Predictions

#265

Post by Robotbeat »

abootstrapper wrote: post #259
Robotbeat wrote: post #210

Earlier quoted context omitted.

I think getting an electric car is even lower hanging. No change in lifestyle, a similar total cost of ownership, but a factor of 2.5-3x lower emissions with even the current grid (and effectively zero emissions in the future grid we'll need anyway). (Plus now you can go on emissions-free road trips.)

Low hanging fruit, assuming you can afford to purchase a new car. Soooo, not so low hanging for a lot of people.

Low hanging fruit assuming you can afford a decent used car. I bought both of my EVs used for $10k apiece (and will save about half of those amounts in gas and maintenance costs...). I see lots of people driving around very large vehicles which, new or used, they probably don't absolutely require and which have both high upfront costs and high operating costs.

I think you'd have more of a point if most people were driving around subcompact beaters.

And remember the context was about someone who can already afford to fly regularly (potentially even overseas), in which case switching to an electric car--if they even require a car--is almost certainly feasible.

Re: Air Travel Emissions Vastly Outpace Predictions

#266

Post by scarejunba »

Lramseyer wrote: post #168

One thing that's very important to keep in mind when looking at air travel emissions is how fuel efficient planes actually are. The math works out to around 100 miles per gallon per passenger. And at an underwhelming 2.5% of global emissions, I can't really put it in the category of "low hanging fruit." That's not to say that we shouldn't invest in things like high speed rail, (because we absolutely will see quality…

The manual choice of what is low-hanging fruit is a path to failure. Instead, we should just tax the emission of the dangerous substance. So today, we'll do CO2. After a while, we'll include CH4. Then with a total cap on carbon, we allow the market to trade the right to carbon.

This will allow money to flow to the right places.

Re: Air Travel Emissions Vastly Outpace Predictions

#267

Post by DuskStar »

mehrdadn wrote: post #249
TulliusCicero wrote: post #191

Earlier quoted context omitted.

People traveling, the tourism that is so often bemoaned, is a huge part of the connections between countries, a huge part of diversity and understanding. A world with greatly reduced air travel is a more insular and less understanding world.

> A world with greatly reduced air travel is a more insular and less understanding world. That's dubious and far more benign than the consequences of a world with climate change.

> That's dubious and far more benign than the consequences of a world with climate change.

I'd rather have a connected world with climate change than a disconnected world with WW3... (and probably still climate change, because war is great for CO2 emissions)

For that matter, how many people will care about the Great Barrier Reef (etc) if there's no possibility of them ever being able to travel there?

Re: Air Travel Emissions Vastly Outpace Predictions

#268

Post by esotericn »

saalweachter wrote: post #201
blunte wrote: post #136

If you need to travel long distances, there's little substitute for an airplane. If air travel accounts for less emissions than passenger cars, and if the top 15 polluting large container ships produce as much (noxious oxides of nitrogen and sulphur) pollution as all cars, then we need to fix shipping first. And if you look at a lot of the crap that is being shipped, it's stuff we just don't need. A lot of things are…

> ... then we need to fix shipping first. The problem with this logic is that we aren't one person looking at a bug tracker queue deciding one to tackle next. We are a civilization . We need to fix everything all at once, as quickly as possible. If shipping is a problem, fix it now . If air travel is a problem, fix it now . If grid electric is a problem, fix it now . If automotive emissions are a problem, fix it now…

Right. 7 billion people is an unfathomable amount.

You don't understand what it means. I don't understand what it means.

A person can tackle a bug in a tracker.

A company can tackle a bug tracker.

A few cities' worth can tackle manufacturing the computer.

The world? We got this. All in.

If we're enough to fuck it up, we're enough to sort it out.

Re: Air Travel Emissions Vastly Outpace Predictions

#269

Post by perfunctory »

martamoreno2 wrote: post #8

2.5% eh? We should all immediately stop flying... This is outrageous. Just imagine, 2.5%!! But on a more serious note, this article is again wrong, like so many others about climate change. Being a combination of clickbait and false assumptions, it fails to miss the point entirely that first, 2.5% are irrelevant, but also that it makes no sense whatsoever to tackle this now. The technology is just not there yet. What…

> What we need to do is to suck out more than we put in.

Doesn’t it violate the first law of thermodynamics or something like that?

Re: Air Travel Emissions Vastly Outpace Predictions

#270

Post by mehrdadn »

DuskStar wrote: post #267
mehrdadn wrote: post #249

Earlier quoted context omitted.

> A world with greatly reduced air travel is a more insular and less understanding world. That's dubious and far more benign than the consequences of a world with climate change.

> That's dubious and far more benign than the consequences of a world with climate change. I'd rather have a connected world with climate change than a disconnected world with WW3... (and probably still climate change, because war is great for CO2 emissions) For that matter, how many people will care about the Great Barrier Reef (etc) if there's no possibility of them ever being able to travel there?

You're worried about CO2 emissions resulting from war? You do realize the role climate change itself can play in migration, refugees, wars, catastrophes..? You need to be worried about climate change resulting in war...
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