Air travel less harmful to the environment than rail travel?

tim..... wrote:

"Nelson" wrote in message
ps.com...

On 14 Aug, 20:13, Darryl wrote:

On Aug 13, 1:54 pm, Nelson wrote:


altitude their shadows cover immense areas. On the other hand vast
quantities of fossil fuels are burnt to produce the electricity (at
only 10% efficiency) to power the railways.

Trains typically use diesel, not electricity (subways & the monorail
at Disneyland not included).

However, if you're going to make up facts to support your position, I
would suggest you pretend that trains are fueled by burning Sequoia
redwoods and American flags, and all the conductors weigh 300+
pounds. These would operate at -25% efficiency, and would make your
argument even stronger.

No need to invent facts look at the web site:-
http://www.bts.gov/publications/nati..._statistics/ht...
able_04_20.html

In 2001 long haul flights 3,965 Btu per passenger mile
In 2001 Amtrack 2100 Btu per passenger mile but does not
include laying and maintaining track, signals etc.


Though Amtrack doesn't exactly run the world most passenger
efficient railway, does it?

tim



There is no U in QANTAS
There is no C in AMTRAK

"mrtravel" wrote in message
. ..
tim..... wrote:

"Nelson" wrote in message
ps.com...

On 14 Aug, 20:13, Darryl wrote:

On Aug 13, 1:54 pm, Nelson wrote:


altitude their shadows cover immense areas. On the other hand vast
quantities of fossil fuels are burnt to produce the electricity (at
only 10% efficiency) to power the railways.

Trains typically use diesel, not electricity (subways & the monorail
at Disneyland not included).

However, if you're going to make up facts to support your position, I
would suggest you pretend that trains are fueled by burning Sequoia
redwoods and American flags, and all the conductors weigh 300+
pounds. These would operate at -25% efficiency, and would make your
argument even stronger.

No need to invent facts look at the web site:-
http://www.bts.gov/publications/nati..._statistics/ht...
able_04_20.html

In 2001 long haul flights 3,965 Btu per passenger mile
In 2001 Amtrack 2100 Btu per passenger mile but does not
include laying and maintaining track, signals etc.


Though Amtrack doesn't exactly run the world most passenger
efficient railway, does it?

tim



There is no U in QANTAS
There is no C in AMTRAK

I didn't think there was. I was just copying the OP and
being mindful not to end up with the name of a delivery
company (which doesn't have the c either)

tim

On 15 Aug, 10:15, "tim....." wrote:
"mrtravel" wrote in message

. ..





tim..... wrote:

"Nelson" wrote in message
oups.com...

On 14 Aug, 20:13, Darryl wrote:

On Aug 13, 1:54 pm, Nelson wrote:

altitude their shadows cover immense areas. On the other hand vast
quantities of fossil fuels are burnt to produce the electricity (at
only 10% efficiency) to power the railways.

Trains typically use diesel, not electricity (subways & the monorail
at Disneyland not included).

However, if you're going to make up facts to support your position, I
would suggest you pretend that trains are fueled by burning Sequoia
redwoods and American flags, and all the conductors weigh 300+
pounds. These would operate at -25% efficiency, and would make your
argument even stronger.

No need to invent facts look at the web site:-
http://www.bts.gov/publications/nati..._statistics/ht...
able_04_20.html

In 2001 long haul flights 3,965 Btu per passenger mile
In 2001 Amtrack 2100 Btu per passenger mile but does not
include laying and maintaining track, signals etc.

Though Amtrack doesn't exactly run the world most passenger
efficient railway, does it?

tim

There is no U in QANTAS
There is no C in AMTRAK

I didn't think there was. I was just copying the OP and
being mindful not to end up with the name of a delivery
company (which doesn't have the c either)

tim- Hide quoted text -

- Show quoted text -

Rail Loses Environmental Advantage?

"Recently, some critics have argued that railways are losing the
environmental advantage they are said to have enjoyed previously. For
example, Roger Ford quotes Professor Roger Kemp of Lancaster
University in the UK and states that if a north-of-London Eurostar
train set is used on a hypothetical 350 km/h high-speed line between
London and Edinburgh (600 km), the energy consumption (estimated at 57
kWh/seat) converted to a crude-oil equivalent is more than that of an
Airbus A321 short-haul aircraft flying between the same two cities."

http://www.jrtr.net/jrtr40/f04_tak.html

And that is just the energy used in propelling the train! Double that
for rail track, power losses, maintenance and land use etc

Those demonstrators at Heathrow should be outside the Eurostar
Stations!

In message .com
Darryl wrote:

On Aug 13, 1:54 pm, Nelson wrote:
altitude their shadows cover immense areas. On the other hand vast
quantities of fossil fuels are burnt to produce the electricity (at
only 10% efficiency) to power the railways.

Trains typically use diesel, not electricity (subways & the monorail
at Disneyland not included).

In Calgary our C-Trains are 100% electrical. Wind generated, actually.

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

Nelson wrote:

Amtrak uses about half the energy in Btu per passenger-mile than an
aircraft according to
http://www.bts.gov/publications/nati...tatistics/html
/table_04_20.html
"In recent years, the company has spent millions on track
improvement, including electrification and straightening curves, as
well as $710 million on 20 new trains sets modeled after the French
bullet train, but not as fast. "

That is very interesting. The other half of the energy budget has
gone on infrastructure.
This is why it costs (for two) £408 to get to Madrid by rail and only
£169 to return by air.

Infrastructure construction doesn't take that much energy. It is very
unlikely that "half" of the energy goes into infrastructure. It is
simply unrealistic conjecture on your part.

As far as cost, energy is a small part of the overall cost of a ticket.
Further, many companies will price tickets on the basis of perceived
value to the customer, and not their costs. Therefore, the final price
of a ticket is no indication of the relative amount of energy consumption
of the two modes.

Looking at it another way, on routes where high speed trains and airlines
compete directly, rail tickets with similar restrictions generally cost
less than airline tickets. Do you feel rail is more energy efficient
than air, based on that measure?

Air travel less harmful to the environment than rail travel? My
conclusion is that there is not much in it.

At the moment, neither mode is a major contributor to global warming.

The argument the environmentalists are making is that air travel is
increasing at a far higher rate than the rate aircraft are gaining in
energy efficiency. Further, there is no practical alternative to the use
of fossil fuels in aircraft. Rail, on the other hand, often uses
electrical power in some countries, or can be converted to electrical
power. That means many alternative energy sources exist for rail, and
they can be more easily controlled, in terms of emissions.

There is also the argument that emissions by aircraft are more damaging,
since they are at higher altitude.

Considering all of the issues, the contribution of aircraft to global
warming will be increasing significantly over the next few decades, while
the contribution of other modes will likely be decreasing. That is the
root of the problem. Given that many believe that drastic action is
needed to reduce greenhouse gas emissions, aircraft are a major problem.

mrtravel wrote:

James Robinson wrote:

mrtravel wrote:

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

Can you cite a source for this report showing the entire US dropped
exactly one degree Celsius and that was directly attributable to the
reduction in aircraft?

Here's one article on the effect:

http://www.sciencenews.org/articles/20020511/fob1.asp

Maybe I misunderstood. I thought your post was indicating the
temperature was 1 degeee (Celsius) cooler.

You misunderstood. I simply posted a link to what appeared to be a
relatively unbiased article that discussed the observations of
temperature change that resulted from the grounding of aircraft. It was
the previous poster who claimed one degree of cooling.


What the article says is that the DTR (difference between the high and
low temperatures) was one degree WIDER. The article doesn't say it was
1 degree cooler, only that the difference between high and low
temperatures increased by one degree. In fact, the report claims the
temperatures increased due to lack of contrails. "—areas of the
country typically blanketed with aircraft contrails in
mid-September—showed the largest changes in diurnal temperature range,
mostly from increased daytime high temperatures"

Please explain your "extra degree of cooling"?
Contrails WARM the surface of the earth, according to the article.

It's not "my" contention, though your sentence above says that the lack
of contrails would cool the earth's surface. Is that what you wanted to
say?

The 1 degree WIDER DTR, according to the article, was due to HIGHER
high temperatures, not lower low ones. This seems contrary to your
report that there was an extra degree of cooling.

Again, it was not "my" report. Be careful of attribution.

There is a certain amount of controversy about the effects of contrails.
Certainly, there was a measured effect on the atmosphere when aircraft
were grounded for those three days, and contrails were not being formed
at the usual rate. The controversy is about what that means in terms of
global warming.

According to a NASA study, the wider swings that were measured would end
up with the net effect of warming the environment by something like 0.1
degrees C. That is a significant amount, especially considering that air
travel is likely to double over the next 15 years or so.

On 14 Aug, 01:02, (Randy Hudson) wrote:
In article .com,
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.

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











--
Randy Hudson

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.

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.

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?

In article .com,
wrote:


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

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


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.

The time difference (door to door), not to mention the quality of life,
is already in favor of the trains today. And it seems pretty obvious
that there will be substantially less environmental impact if this can
come to be.

James Robinson wrote:
wrote:


(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.