The Emissions Race is on Between Cars, Buses & Jets

Driving a car increases global temperatures in the long run, more than making the same long-distance journey by air according to a new study. However, in the short run travelling by air has a larger adverse climate impact because airplanes strongly affect short-lived warming processes at high altitudes. But help is at hand. China has come up with a novel and cleaner traffic congestion buster – a straddling bus that literally overtakes cars!

By Peter Farquhar, Technology Editor (4 August 2010):  

IMAGINE one day you’re stuck in a smelly Beijing gridlock and you’re suddenly overtaken by a bus.

Not just overtaken, but overtaken. As in, over the top of your car.

This alarming, yet weirdly sensible concept was flagged at the 13th Beijing International High-tech Expo in May this year.

It’s called the “3D Fast Bus”, despite the fact it’s not really very fast at all with a top speed of just 60km/h.

Still, that’s more than the 1200-1400 passengers on board could hope during rush hour, with Chinese commuters this year snapping up cars faster than their US counterparts for the first time.

Subways are disruptive and extremely expensive to build. Regular buses add to traffic jams and pollution levels.

The “straddling bus” proposed by Shenzhen Hashi Future Parking Equipment solves both these problems, and is designed to be powered by a combination of solar power and electricity.

Up to 4.5m high, it allows traffic to flow under it and can reduce traffic jams by up to 30 per cent, according to its creators.

It will cost about 10 per cent of the equivalent of building a similar 40km subway system.

Shenzhen Hashi says it would run on a track straddling both sides of existing roads and could be built within a year — a third of the time it would take to build a subway.

So far, so sensible.

However, another option, says Shenzhen Hashi is to do away with the track and simply create an autopilot system which follows two white lines painted on either side of the road. Graffiti terrorists take note.

There’s also a few other nagging problems, such as what if trucks get pushy?

One solution is using “ultrasonic waves” which emit from either end of the bus to warn the driver that something’s not quite right.

Laser rays that scan traffic will activate alarms inside the bus if there’s a danger of lopping the top off a big rig.

Drivers will also have to keep their wits about them while passing through the bus, but red flashing lights will warn drivers if its about to turn or if they’re too close to the interior walls.

Unrealistic? Not quite.

If it sounds like a good idea that just has some ironing out to do, think again.

Shenzhen Hashi says it’s already got its first order and the 3D Fast Bus has already passed “the first stage demonstration”.

Beijing’s Mentougou District has already planned out 186km for it and construction will begin by the end of the year.

Source:   www.news.com.au

Release from the American Chemical Society (4 August 2010):

Driving a car increases global temperatures in the long run more than making the same long-distance journey by air according to a new study. However, in the short run travelling by air has a larger adverse climate impact because airplanes strongly affect short-lived warming processes at high altitudes.

The study appears in ACS’ Environmental Science & Technology, a semi-weekly journal.

In the study, Jens Borken-Kleefeld and colleagues compare the impacts on global warming of different means of transport. The researchers use, for the first time, a suite of climate chemistry models to consider the climate effects of all long- and short-lived gases, aerosols and cloud effects, not just carbon dioxide, resulting from transport worldwide.

They concluded that in the long run the global temperature increase from a car trip will be on average higher than from a plane journey of the same distance. However, in the first years after the journey, air travel increases global temperatures four times more than car travel.

Passenger trains and buses cause four to five times less impact than automobile travel for every mile a passenger travels. The findings prove robust despite the scientific uncertainties in understanding the earth’s climate system.

“As planes fly at high altitudes, their impact on ozone and clouds is disproportionately high, though short lived. Although the exact magnitude is uncertain, the net effect is a strong, short-term, temperature increase,” explains Dr. Jens Borken-Kleefeld, lead author of the study.

“Car travel emits more carbon dioxide than air travel per passenger mile. As carbon dioxide remains in the atmosphere longer than the other gases, cars have a more harmful impact on climate change in the long term.”

ARTICLE FOR IMMEDIATE RELEASE 
“Specific Climate Impact of Passenger and Freight Transport”

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http://pubs.acs.org/stoken/presspac/presspac/full/10.1021/es9039693

Source: www.eurekalert.org