Roland Perry wrote:

In message , at 12:36:09 on
Tue, 11 Oct 2011, Bruce remarked:

Aircraft emissions are overall slightly greenhouse negative

That sounds interesting, but could you explain what that means in
simple, non-technical English?

It means that if you add up the greenhouse contributions of the
emissions it's slightly negative. Although you can probably find people
who disagree. Greenhouse politics is a bit like that. "Often in error,
but never in doubt" [of their being correct] as someone said.

Some of the contributions a SO2 reflects heat as well as the
contrails. The engines burn some atmospheric Methane, but nitrous oxides
react with it as well, so there's another reduction in greenhouse
effect.

Looking at growth, air transport is increasing at 4% a year globally,
but set against that there's a 2% per annum increase in fuel efficiency.


Thanks. I'm still not sure what you mean by "slightly negative". A
negative contribution to greenhouse gases might be generally positive,
which is why I am confused.

As to your more general point about 'greenhouse politics', a major
research project that was carried out under the auspices of IPCC has
identified (with a high degree of confidence) the cause of at least
half of the warming of the last 150 years. It may account for even
more of the warming, as much as two thirds.

But the cause has nothing whatsoever to do with carbon emissions, so
the findings don't fit the IPCC's anti-fossil fuels mantra and have
been dismissed. That's a prime example of 'greenhouse politics'
overriding good science.

d wrote:

Anyway , have a look at http://www.flightradar24.com to see the shear
numbers of aircraft in the sky already over europe. Personally I think its
quite enough given the precarious state of the enviroment at the moment.


You are either a scaremonger, or a victim of scaremongering, or both.

On Tue, 11 Oct 2011 13:00:22 +0100
Roland Perry wrote:
It means that if you add up the greenhouse contributions of the
emissions it's slightly negative. Although you can probably find people
who disagree. Greenhouse politics is a bit like that. "Often in error,
but never in doubt" [of their being correct] as someone said.

Some of the contributions a SO2 reflects heat as well as the
contrails. The engines burn some atmospheric Methane, but nitrous oxides
react with it as well, so there's another reduction in greenhouse
effect.

What a load of cock. SO2 soon reacts with water and comes out of the
atmosphere of its own accord and Methane reacts with O2 eventually anyway
plus most of it is near ground level, not at 30,0000 feet.

As for contrail reflections, they reflect heat out into space but also
back down towards the earth which doesn't help at night. So once everything
everything out you're left with the 500 million tons of CO2 that
aircraft pump out each year.

Looking at growth, air transport is increasing at 4% a year globally,
but set against that there's a 2% per annum increase in fuel efficiency.

Well thats ok then, its only going up by 2% each year.

B2003

On Tue, 11 Oct 2011 13:32:43 +0100
Bruce wrote:
wrote:

Anyway , have a look at http://www.flightradar24.com to see the shear
numbers of aircraft in the sky already over europe. Personally I think its
quite enough given the precarious state of the enviroment at the moment.


You are either a scaremonger, or a victim of scaremongering, or both.

Sorry? Do you think the aircraft shown on that site are made up?

B2003

d wrote:

On Tue, 11 Oct 2011 12:41:16 +0100
Bruce wrote:
My point was that the aircraft lobby has very little to do with how
many flights are operated. That is more likely to be dictated by
customer demand. The aircraft lobby, whoever they are, are probably

And customer demand is partially driven by advertising on the part of the
holiday companies and airlines. They're not merely bystanders in the process.

The main driver of demand appears to be the low cost of air travel.

Agreed.

What would choke off demand very effectively is an increase in the
cost of tickets, via an increase in the cost of fuel, taxation or some
levy on carbon emissions, or any combination thereof.

Well aircraft fuel should certainly be taxed. I see no reason why airlines
should have some special status over other transport operators.


I agree that it should be taxed, however there is a very good reason
why it isn't, which is because of international treaties.

The whole issue of taxation of transport is a minefield. For example,
annual spending on roads in the UK is just over £6 billion, yet the
revenue raised from road users is many times higher. Meanwhile, the
annual spending on rail is slightly higher at about £6.3 billion,
despite the fact that it provides less than 7% of transport versus the
93% that goes by road, yet the tax take from rail is minimal.

I don't see anything fundamentally wrong with road users being charged
more than the cost of building and maintaining the road network, but
taxes and duties on road users are between eleven and sixteen times
higher than roads expenditure (depending on whose figures you accept)
which seems hugely disproportionate.

Against that, the zero tax and duty on aviation fuel seems much too
far in the other direction. Having said that, I would not like to see
the cost of my annual flight to the Caribbean going up ...

In message , at 13:31:30 on
Tue, 11 Oct 2011, Bruce remarked:
Aircraft emissions are overall slightly greenhouse negative

Thanks. I'm still not sure what you mean by "slightly negative". A
negative contribution to greenhouse gases might be generally positive,
which is why I am confused.

That's why I didn't use the words "greenhouse *gases*", because they are
only part of the picture. The overall "greenhouse" or "global warming
effect" (taking into account all the factors I mentioned) can be
calculated to be negative.

The main message is that the positive CO2 isn't the only story, although
contrails are fairly well accepted. But even then the contrail effect is
an aggregate because they cool in the day and warm at night!
--
Roland Perry

In message , at 12:47:36 on Tue, 11 Oct
2011, d remarked:
Some of the contributions a SO2 reflects heat as well as the
contrails. The engines burn some atmospheric Methane, but nitrous oxides
react with it as well, so there's another reduction in greenhouse
effect.

What a load of cock. SO2 soon reacts with water and comes out of the
atmosphere of its own accord and Methane reacts with O2 eventually anyway
plus most of it is near ground level, not at 30,0000 feet.

As for contrail reflections, they reflect heat out into space but also
back down towards the earth which doesn't help at night.

But nevertheless, add up all the contributions, even if some are short
term, and I've told you the answer.

So once everything everything out you're left with the 500 million
tons of CO2 that aircraft pump out each year.

That's about the same as emissions from petroleum and natural gas in the
UK alone.

--
Roland Perry

In message , at 12:48:04 on Tue, 11 Oct
2011, d remarked:
Anyway , have a look at http://www.flightradar24.com to see the shear
numbers of aircraft in the sky already over europe. Personally I think its
quite enough given the precarious state of the enviroment at the moment.

You are either a scaremonger, or a victim of scaremongering, or both.

Sorry? Do you think the aircraft shown on that site are made up?

The effect of them (as reflected by yourself) is, though.
--
Roland Perry

On Tue, 11 Oct 2011 14:04:32 +0100
Roland Perry wrote:
So once everything everything out you're left with the 500 million
tons of CO2 that aircraft pump out each year.

That's about the same as emissions from petroleum and natural gas in the
UK alone.

Oh ok , if you're going to play that game then why worry about any form of
pollution since none of them individually come close to the total? I'm sure
there's a name for that sort of deceptive argument but I can't remember what
its called.

B2003

Roland Perry wrote:
In message , at 12:58:47 on
Tue, 11 Oct 2011, Bruce remarked:
What they can't do is *start building* until 2019. I originally thought
they couldn't apply for planning permission until 2019, but it's not
even that.

That is what I thought too. I researched it in some detail in the
1990s as I lived in an area of Sussex that already had quite a lot of
aircraft noise and would have had more if the changes had gone ahead.

My information is from 2005, so post-dates your research. Maybe 2019 was
redefined, but it's currently the limit on building work, not planning.


Thanks. I left the area in 1998 and haven't kept in close touch with
what's happening, so I accept that a lot may have changed since then.

At that time, the scheme that had previously been proposed for the
second runway had a separation from the existing runway of nowhere
near 1.0 km, so it is obvious that there has been at least one
significant change.

The previous proposal kept to a minimum the amount of demolition that
would be needed. I think it was limited to part or all of one
industrial estate. I would imagine that a 1.0 km separation would
involve much more demolition as the new runway would be significantly
closer to Crawley. The noise nuisance would also be worse.

If you have a link to anything that explains the 2005 proposals I
would be interested.