Air travel less harmful to the environment than rail travel?

On 23 Aug, 17:34, James Robinson wrote:
wrote:
@panix.com (Randy Hudson) wrote:

Nelson wrote:

Aircraft leave vapour trails which aid in the reflection of
the sun's radiation back into space.

A study of the no-fly period following 9/11 showed a full extra
degree (Celsius) of cooling over the US during those four days,

I think you mean warming..! According to the theory it is masking
global wamring.

On the contrary. The theory is that while the creation of cirrus clouds
will reflect sunlight during the day, the presence of the clouds will
also trap heat overnight. The net effect of both is supposed to increase
temperatures by something like 0.1 degrees C, at least according to a
NASA report, which seems to be conservative.

So we have two hyotheses.

apparently due to the lack of contrail vapor, which contributes to
the cirrus cloud layer that reflects nighttime longwave radiation
back to earth.

Any efficiency calculation should factor in time saved. In this case
jet power flight does rather better (for longer journeys of course).

Also flying usually 10 x smoother than rail. I have real trouble
using laptop on some trains, even with the additional space.

Time savings is immaterial when considering the effects on global
warming. The fact that somebody saves time does not compensate for
destruction of the planet, if you believe the warnings of those who
contend humanity needs to change they way we do things.

Of course if you decide to look at it such a one-dimension way.

But any assessment has to look at benefits as well as any costs.
Some people believe we should give up motoring because of the death
toll on the roads. That is an obvious conclusion if you have a one-
dimensional outlook, but it is not way most people look at it.



As far as laptop use, rail can be rougher, but 10X exaggerates the
difference.

Further, with rail-competitive journeys, how much would you be able to
use the laptop on an aircraft anyway, considering you can't use them
during ascent or descent?

wrote:

James Robinson wrote:

Time savings is immaterial when considering the effects on global
warming. The fact that somebody saves time does not compensate for
destruction of the planet, if you believe the warnings of those who
contend humanity needs to change they way we do things.

Of course if you decide to look at it such a one-dimension way.

But any assessment has to look at benefits as well as any costs.
Some people believe we should give up motoring because of the death
toll on the roads. That is an obvious conclusion if you have a one-
dimensional outlook, but it is not way most people look at it.

Global warming is a black and white issue to those who strongly believe
that it will be catastrophic. As I said, if the choices are between
wiping out civilization and inconvenience, there would be little debate.

Instead, the argument is whether those who believe that climate change is
a precipice with no ability to recover are correct.

"Most" people are not well informed about the science behind global
warming, so are not equipped to decide on way or the other whether they
should be inconvenienced, or simply continue business as usual. However,
there have been enough convincing studies to sway many countries to take
some action to reduce greenhouse gas emissions, supported by their
electorate. The actions have been mostly ineffective.

mrtravel wrote:

James Robinson wrote:

wrote:

@panix.com (Randy Hudson) wrote:

Nelson wrote:

Aircraft leave vapour trails which aid in the reflection of
the sun's radiation back into space.

A study of the no-fly period following 9/11 showed a full extra
degree (Celsius) of cooling over the US during those four days,

I think you mean warming..! According to the theory it is masking
global wamring.

On the contrary. The theory is that while the creation of cirrus
clouds will reflect sunlight during the day, the presence of the
clouds will also trap heat overnight. The net effect of both is
supposed to increase temperatures by something like 0.1 degrees C, at
least according to a NASA report, which seems to be conservative.

But that isn't what this report said. It said the temperature
deviation, during the air travel restrictions during the days after
9-11 were one degree more than normal and this was due to the increase
in the high temperatures.

That report was simply a comment on the effect following 9/11, and it
confirmed that contrails tended to dampen the diurnal temperature change.
I posted the link as it responded to the earlier poster's comments on
average temperature change.

The data gained from the shutdown following 9/11 have allowed climate
forecasters to calibrate their models of global climate in the absence of
contrails. The general conclusion is that contrails contribute to global
warming. That conclusion is not universally held, and there is much
debate on whether the change is significant enough to be worried about.

You are always free to post your own links to appropriate discussions.

In message AES
wrote:

One has to have some hope that for journeys under, say, 300 or 500
miles, U.S. train service will eventually evolve to reach the level of
comfort, convenience, and generally pleasant experience that one can
routinely get today on, say, German intercity trains.

And with German intercity trains covering a space smaller then the state
of Texas, it likely works well.

The magnitude of order of difference in the scale doesn't favour trains
in North America.

For shorter trips though, it would definitely be fantastic!

--
You can get more with a kind word and a 2x4 than just a kind word.

On 24 Aug, 10:40, James Robinson wrote:
wrote:
James Robinson wrote:

Time savings is immaterial when considering the effects on global
warming. The fact that somebody saves time does not compensate for
destruction of the planet, if you believe the warnings of those who
contend humanity needs to change they way we do things.

Of course if you decide to look at it such a one-dimension way.

But any assessment has to look at benefits as well as any costs.
Some people believe we should give up motoring because of the death
toll on the roads. That is an obvious conclusion if you have a one-
dimensional outlook, but it is not way most people look at it.

Global warming is a black and white issue to those who strongly believe
that it will be catastrophic. As I said, if the choices are between
wiping out civilization and inconvenience, there would be little debate.

Instead, the argument is whether those who believe that climate change is
a precipice with no ability to recover are correct.

Nature is random chaos not harmony. There is no scientific reason to
buy into Gaia theory.