Night flights worsen climate change: study

Restrictions on night flights could ease the aviation industry's fast-growing contribution to global warming, a study says.

At certain altitudes, aircraft produce contrails, the vapour wake caused when water in the chilly atmosphere is condensed by the plane's hot exhaust.

These contrails have a surprisingly big but also complex effect on the climate.

Because they are clouds, they trap heat that is emitted by the Earth's surface, creating a "greenhouse effect" that adds to warming.


http://www.abc.net.au/news/newsitems/200606/s1663385.htm

Except for things like urgent express packages like donor organs, there ought to be no air travel whatsoever.

We need a new generation of ships and trains to replace all air travel.

I hate flying in planes.

I'll take the train any time.

That is one hot ride!

I lived on O'ahu for about 20 years. I would never have been able to see family in California AT ALL if I'd had to take a ship. When you fly, it takes a day. When you float, it takes many days, a week -- during which time you pay for a bed and meals. Vacation time gets eaten up in a hurry.

So yes, alternative means of mass transit are a terrific idea, but let's not go to extremes.

Hekate

A fast (100 km/hr) hydrofoil would make the trip in 48 hours.

Zero emissions, ya scurvy dogs

Since jets are introducing pollutants into an environment that has little cleaning ability, the pollutants last and last.

It may be that we are seeing the last of either life as we know it or life as the just jet-setters know it.

"At certain altitudes, aircraft produce contrails, the vapour wake caused when water in the chilly atmosphere is condensed by the plane's hot exhaust."

the vapour wake caused when water in the the plane's hot exhaust is condensed by the chilly atmosphere

when planes were grounded for a few days.

http://www.agiweb.org/geotimes/june04/geophen.html

and I'll keep saying it. Water vapor is 60% of greenhouse gas effect. Water vapor in the upper atmosphere is even more of a contributor.

Please note that it is not condensed water, but water vapor and at extreme altitudes there is always an exchange between the phases (solid, fluid and gas/vapor)

The news story is not completely accurate.

to the point it ceases to make sense. There are two issues : global warming and global dimming. Warming is contributed to by CO2 trapped in the atmosphere but dimming is a whole different issue. Dimming reduces the amount of sunlight reaching the ground and has a cooling effect. The contrails form ice on pollutant particles and increase the size of those particles. The particles then act as mirrors reflecting sunlight back outwards.

The paradox is that if you reduce global dimming by removing pollutants you increase global warming as a result. Attention was first drawn to golobal dimming when it found that the amount of sunlight reaching the ground in Israel has reduced by c. 20% over the past 50 years.
The claim was initially dismissed as preposterous but similar results were then found elsewhere. Search global dimming and you find all of the answers.

The link is to a better account of the study:

http://www.newscientist.com/article/mg19025564.900.html

Please note the difference in water vapor and clouds. Water vapor is essentially invisible and clouds are made up of water droplets and ice crystals.

Here's one of the links to global dimming. It's the transcript of the BBC Horizon TV program which was devoted to the subject as part of their Climate Change series :

http://www.bbc.co.uk/sn/tvradio/programmes/horizon/dimming_trans.shtml

It mentions the paradox whereby if you remove global dimming then global warming will accelerate.