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Air Travel Emissions Vastly Outpace Predictions

nytimes.com

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Re: Air Travel Emissions Vastly Outpace Predictions

#191

Post by TulliusCicero »

mehrdadn wrote: post #143
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…

> If you need to travel long distances, there's little substitute for an airplane. The emphasis here isn't on substitute, it's on "need". Not many people need to travel long distances on a regular basis; they're just made to believe they need do.

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.

Re: Air Travel Emissions Vastly Outpace Predictions

#192

Post by semi-extrinsic »

jdc wrote: post #185
bt848 wrote: post #174

Earlier quoted context omitted.

You seem to have conflated CO2 with other pollutants. All the world's shipping taken together amounts to only 3% of the carbon emission inventory. It certainly is not the case that 15 ships emit more carbon than all cars.

Where does the 3% figure come from? It's not clear to me that we have or are even trying to get accurate sea-based emissions inventory.

You can get a very good inventory just from sales of petroleum-based fuel to the shipping industry. Nobody buys diesel or LNG except to burn it.

Re: Air Travel Emissions Vastly Outpace Predictions

#193

Post by nateburke »

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…

Yes, while 100 mpg per passenger is roughly 2x the best hybrid car, the presence of air travel as an option, especially in a business context allows individuals to accrue many orders of magnitude _more miles_.

MPG per passenger is the wrong unit.

Gallons per person per hour of active transport seems like a better unit to measure.

For example, say your non-hybrid car gets 30 mpg, and you average 30 miles per hour between city/highway, you're at 1 gallon per hour per passenger, assuming 1 person per car.

For air travel averaging out at 500 mph, the 100 miles per gallon per passenger equates to 5 gallons per hour per passenger.

So you would need to pack a plane with 5x the number of people that the 100 mpg number was measured at to even COME CLOSE to hitting the miles/passenger-hour of a non-hybrid car driven by a single driver.

That's a crowded plane.

Re: Air Travel Emissions Vastly Outpace Predictions

#194

Post by blunte »

jdc wrote: post #185
bt848 wrote: post #174

Earlier quoted context omitted.

You seem to have conflated CO2 with other pollutants. All the world's shipping taken together amounts to only 3% of the carbon emission inventory. It certainly is not the case that 15 ships emit more carbon than all cars.

Where does the 3% figure come from? It's not clear to me that we have or are even trying to get accurate sea-based emissions inventory.

This article: https://www.economist.com/finance-and-economics/2017/03/11/g...

Re: Air Travel Emissions Vastly Outpace Predictions

#195

Post by sokoloff »

reaperducer wrote: post #180
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 math works out to around 100 miles per gallon per passenger. That assumes maximum passenger load, I assume. At maximum passenger load, my car gets 170 miles per gallon per passenger. A giant, gas-guzzling Chevy Suburban gets 198 miles per gallon per passenger. I don't think "per gallon per passenger" is a useful measure.

I think it is.

Freight is typically measured in cargo-ton-miles per gallon. I can't think of a reason to measure airline travel in other than passenger-miles per gallon. (You have to do it "as flown" and "as driven" for the comparison to be meaningful, but it's pretty rare for me to see anything under a 90% full flight lately with the economy booming.)

Re: Air Travel Emissions Vastly Outpace Predictions

#196

Post by djmips »

reaperducer wrote: post #180
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 math works out to around 100 miles per gallon per passenger. That assumes maximum passenger load, I assume. At maximum passenger load, my car gets 170 miles per gallon per passenger. A giant, gas-guzzling Chevy Suburban gets 198 miles per gallon per passenger. I don't think "per gallon per passenger" is a useful measure.

Just feel like pointing out that airplanes are flown maximum passenger load or close to it as much as possible whereas you can see just by looking around in traffic that passenger cars are mainly driven with one person inside.

Re: Air Travel Emissions Vastly Outpace Predictions

#197

Post by Aloha »

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…

This is what humanity does best, we innovate our way out of problems (often ones we created in the first place)

Re: Air Travel Emissions Vastly Outpace Predictions

#198

Post by phil248 »

munk-a wrote: post #9
DisruptiveDave wrote: post #7

Earlier quoted context omitted.

> Telecom technology has matured enough to make personal presence unnecessary Holy moly that's sad if anyone actually believes this.

I actually believe this, could you maybe expand on for what interactions you think personal presence is still necessary and adds real value?

Many, many sales people would say... sales.

Re: Air Travel Emissions Vastly Outpace Predictions

#199

Post by bluGill »

WhompingWindows wrote: post #103
misiti3780 wrote: post #2

"Over all, air travel accounts for about 2.5 percent of global carbon dioxide emissions — a far smaller share than emissions from passenger cars or power plants." 2.5% means we should focus on reducing somewhere else in the near term.

Near term, we should be slamming money into batteries and energy density of said batteries, if we want to decarbonize air-travel. Electric planes have numerous advantages, but jet fuel is just so much more energy dense than a battery at the current juncture. Hopefully by 2050, we will be able to scale up from smaller electric airplanes in the 2020-2030 timeframe, such that jet liners will be decarbonized too.

My understanding of the laws of physics that govern batteries is we are already close to the limits. There might be a doubling or two of capacity left, but that doesn't get us anywhere near the weight/energy ratio of jet fuel.

There are options to make fuels from other sources - but every time someone brings this up we get the oil shrills screaming about why use food for fuel, or their tired old energy neutral studies that haven't changed their numbers in 20 years.

Re: Air Travel Emissions Vastly Outpace Predictions

#200

Post by semi-extrinsic »

Supermancho wrote: post #188
bt848 wrote: post #174

Earlier quoted context omitted.

You seem to have conflated CO2 with other pollutants. All the world's shipping taken together amounts to only 3% of the carbon emission inventory. It certainly is not the case that 15 ships emit more carbon than all cars.

> It certainly is not the case that 15 ships emit more carbon than all cars. That is correct. However, the pollutants that the referenced ships produce are far more hazardous (immediately) and in greater volumes than many countries produce (in aggregate) per year. To put it in perspective...warning: this is an analogy that mixes metaphors: Talking about CO2 emissions while Nuclear Waste is constantly being pumped int…

I don't follow what you're saying. Is it that other emissions than CO2 are more important to fight?

Well, that change is already happening with the ongoing big change towards LNG as the preferred fuel for shipping.

But when it comes to reducing CO2 emissions, outside of improving energy efficiency, it seems nobody has anything even remotely viable today. That goes both for deep sea shipping and for most air travel.

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