Road Traffic Pollution Factor Higher Than Aviation
A new study by the Center for International Climate and Environmental Research (CICERO) of Oslo Univerity (Norway) into pollution due to transport has pointed out that road traffic is the worst. Greenhouse gas emissions from aviation, by comparison, are less, say the researchers. But aviation is the second-largest pollutor.
The study has one more surprising outcome; shipping has a cooling effect on the environment. Aside from the road, aviation and shipping transport sectors, the study also looked at the railways. The researchers calculated what’s known as ‘radiative forcing’ (RF) for each sector. RF is the net warming effect in unit Watts per square meter (W/m2).
The five researchers involved in the study say that since preindustrial times the transport sector has been responsible for 15 percent of the RF caused by man-made CO2-emissions and the road transport also seriously damagest the ozon layer.
If anything, the study’s outcome underlines that the fast growing road sector is truly worrisome. “The road emissions of today will constitute three- fourth of the warming caused by transport over the next hundred years”, say the researchers.
The reason that road transport tops the list is mainly the amount of vehicles on the roads and the smaller cooling effect, say the Norwegian researchers. They are planning to supplement the study with a calculation per kilometre or per person at a certain distance using different transport modes. That’s hugely exciting. Stay posted on this blog for details when they become available.
Shipping is a different story altogether. This form of transport cools the climate because shipping emits large portions of the gasses SO2 and Nox, positive coolants. But, the researchers warn, the effect will diminish as time elapses, because SO2 and Nox don’t hang around very long; “After a few decades, the long-lived CO2 will dominate, giving shipping a warming effect in the long run”, say the researchers. At the same time, both SO2 and NOx have other impacts that damage the environment. The two emissions are not covered by the Kyoto Protocol.
Aviation is second in the research because the researchers opted for a historical approach. The historical contribution from aviation emissions to global warming is more than doubled by the contribution from road emissions. “Over the next 100 years, today’s road emissions will have a climate effect that is four times higher than the climate effect from today’s aviation emissions”, the researchers say.
They add that the transport sector’s contribution to global warming will continue to be high and they estimate that current emissions from transport are responsible for approximately 16 percent of the net radiative forcing over the next 100 years. The dominating pollutant is CO2, followed by tropospheric O3. The warming effect by rail emissions is negligeable compared to those by road transport and aviation.
The study is entitled “Climate forcing from the transport sectors”. Stay posted here for updates!
Entry filed under: Green News.