Why Singapore must act to cut vehicle soot now

Dennis Posadas Today Online 16 Jun 13;

Walk around many major Asian cities like Shanghai , Bangkok and Manila for a few minutes during the peak hour rush, and the impact of unburned fossil fuel soot will immediately be apparent in your lungs, your hair and skin.

Soot (known technically as black carbon) is the unburned component of fossil fuels such as diesel and gasoline from poorly maintained and dilapidated vehicle engines, cookstoves and the like.

But most of Asia’s transportation systems, especially in poor countries and even China , consists of surplus and dilapidated engines that are not always properly maintained. Thus soot is a major problem, and given the number of decades it has persisted, it would not be surprising to conclude that nothing can be done – that it is a common problem that everyone talks about but no one wants to solve.

Economists call the ill effects an externality – in this case refering to respiratory ailments such as asthma, bronchitis, allergic rhinitis and the like. These result in real costs – hospital visits, asthma inhalers, so on – but still nothing is done about it, save for anti-smog laws that are often bypassed and sources of corruption in many cities.

But many scientists around the world, such as Dr Veerabhadran Ramanathan of the University of California at San Diego (http://www.nature.com/ngeo/journal/v1/n4/full/ngeo156.html) have found that black carbon is a very powerful climate change agent several thousand times more potent than carbon dioxide. Because the soot particles are black, just like a black car in the summer, when sunlight strikes it, it does not reflect light but instead emits heat – as a black body, to its surroundings.

When carried by winds to Arctic (and Himalayan) ice, it also reduces the reflectivity of these ice sheets, thus reducing the ability of ice sheets to reduce solar heat.

This finding allows black carbon to be treated as a climate change agent in much the same way that the other greenhouse gases are, meaning that financing mechanisms that allow for the building of solar and wind farms technically should be allowed for financing repair of dilapidated old engines and cookstoves.

To this end, the UNEP Climate and Clean Air Coalition (CCAC) to reduce short lived climate pollutants (such as black carbon, HFC refrigerants, and methane) is studying how to move forward on this.

According to the UNEP, “rapidly reducing methane and black carbon could prevent over two million premature deaths and avoid annual crop losses of over 30 million tons annually. It could also slow down the warming expected by 2050 by about 0.5-degrees Celsius, almost halving projected near-term warming, while mitigating emissions of HFCs could augment this global mitigation potential by about 20 per cent.

“Reducing SLCPs is also likely to have enhanced climate benefits in many vulnerable regions such as elevated snow and ice covered regions and in reducing regional disruption of traditional rainfall patterns.”

If we do not move on this, it would be a pity, as fixing black carbon might be as simple as proper maintenance to, at worst, repairing or replacing a defective engine.

Unlike carbon dioxide, which remains in the atmosphere for many decades even if coal sources are displaced by renewable sources, black carbon disappears from the air only after a few weeks once the offending source is corrected. Thus black carbon efforts are a good way to move on the climate front while at the same time tackling what has been long a struggle for many cities – the respiratory health of their inhabitants.

ABOUT THE AUTHOR:

Dennis Posadas is an Asia-based fellow of the Washington D.C. based Climate Institute and author of Greenergized: A Business Fable on Clean Energy.