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Comment by jokoon | Hacker News Reader

Yeah I guess that's a good way to start discussing investments in railroad and nuclear energy.

I don't think a more efficient jet engine will make air traffic environment-friendly anytime soon.

Sorry to hijack the conversation.

Efficiency, when talking about mature markets, is rarely about emissions, it is about cost. We could have zero net emissions today by using pure hydrogen or biofuels in existing turbofans with little modification.

It does, however, matter quite a bit for emerging technologies which may be aimed at lowering emissions. Higher efficiency, for example, can overcome a lot of drawbacks that come with new technologies, like power to weight ratios. Electric cars, for example, have nowhere near the amount of energy storage that gas fueled cars do, but they are now getting similar ranges because they convert it to kinetic energy much more efficiently.

Sure, but I think cows producing methane is probably more harmful and more immediately easy to fix (i.e. I'd rather go on holiday than eat meat). The Earth can probably support air travel if we can get rid of most other sources of greenhouse gases.

There may be solutions to that in the form of feed additives to reduce methane emissions.[1] But as that source notes "methane from animal agriculture is just 5 percent of the total greenhouse gases produced in the United States -- much, much more comes from the energy and transportation sectors", so I'm a skeptical to the suggestion that it is more harmful and easier to fix.

[1]: https://www.sciencedaily.com/releases/2019/06/190617164642.h...

This is an excellent diagram that breaks everything down [1]. It actually shows you are probably right, meat vs air production, meat is 2.5% and air is at 3.3% of greenhouse gases.

[1] https://static.skepticalscience.com/pics/us-flowchart.jpg

Methane is not long lasting unlike CO2.

Cow worries are just smoke to hide the real issue that is the fossil fuels, specially boats and planes.

What's easier to do telling people to stop eating steak, or getting governments to reduce their biggest "sponsors" earnings?

Livestock emit methane (although there are potential solutions for that), and they also can help development of topsoil, and sequester a lot of carbon, when they're grazing and not force fed corn and grain in a feedlot.

Also note that North America used to have as many as 60 million Bison, versus about 95 million cattle today. And cattle emit about as much or less methane than bison do, per animal.

https://daily.jstor.org/can-cows-help-mitigate-climate-chang...

Doesn't methane usually have a short lifespan in the atmosphere?

neither solve the issues air travel does. the amount of rail needed to funnel the same amount of traffic one of the larger airports generate would be phenomenal let alone where could you even put it down? then of course comes the small problem of how many miles cross ocean which puts rail right out of the equation.

Seriously, look at an airport. get the number of flights and where they come from and their frequency, now imagine trying to build a sufficient number of rail lines to do the same.

air travel saves time that no rail line could except in short hop scenarios where extra time to process through an airport might tip a balance. let alone you can have nearly an number of planes in flight between two points

you're comparing status quo (super cheap flights, arguably borderline too cheap to be economically sustainable even without factoring in carbon and water vapor externalities) with something that doesn't even exist and then proclaim it's out of the equation. change prices and the equation may surprise you.

London Victoria rail station averages ~207k passengers per day. London Heathrow airport average ~211k. Doesn't feel that unfeasible.

Victoria is the second busiest station in London - Waterloo is busiest, at about 258 passengers a day

Does London Victoria have trains going to Canada, Hong Kong, Moscow? I am pretty sure most Heathrow flights aren’t to Leeds.

The point is: take airplanes where it makes sense (long distance > 600km), and a well-meshed train network for everything else.

Howrah railway station in India handles over 2 million passengers per day.

The number of seats in a long distance train in India with about 24 coaches is about 1780 not including those without seats.

> the amount of rail needed to funnel the same amount of traffic one of the larger airports generate would be phenomenal let alone where could you even put it down?

A fully loaded ICE 4 high speed train can pack 830 people, an A380 615.

> get the number of flights and where they come from and their frequency, now imagine trying to build a sufficient number of rail lines to do the same.

The answer is multimodal transport and connections. With airplanes, transit takes time and effort - with trains, next to zero. Take, for example, a traveller from New York (USA) to Gaimersheim (DE, Bavaria): airplane connects New York to Munich. Then you travel with the S-Bahn regional train to Munich Central train station, take an ICE high-speed train to Ingolstadt, and switch to the regional train which takes you to Gaimersheim.

Air traffic is a luxury that's not really warranted or necessary. It has a huge environmental cost. I never said rail is faster and better, it's just necessary to prevent climate change that will kill billions of people.

If in the future some modes of transportation are banned, everybody will feel sorry to not have enough railroad and nuclear energy.

Chiming in from Hamburg, Germany with its main station at 550.000 pax per day in 2018. About crossing the oceans: What about floating submerged pipes, maybe going to artificial island hubs in international waters with blackjack and hookers? Has the hype left the loop? Where is your VISION?

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