Does China's pollution affect the planet?
THURSDAY OCTOBER 01, 2009
It is advised not to lose sight of real science and actual observation. City smog, haze etc does not go above a few hundred feet. You can look down on Auckland smog from the summit of Mt Atkinson in Titirangi. The amount of CO2 in the air is always only around 38 parts in 100,000. CO2 is not one of the impurities. Thousands of tons of water are lifted each day from the oceans by evaporation. This water is free of impurities - that is the nature of distillation.
A low pressure system can range for hundreds of miles and drop rain over an area as big as the Tasman Sea. The amount of soot particles from industry and emissions from a city is infinitesimal and does not contribute to weather. And being heavier than air, in less turbulent parts of the atmosphere pollution particles drop out when they can.
Water vapour always rises because it is lighter and separates away. Look out of a Boeing window and you will see, like white candy floss, streaky ice crystal cirrus cloud above the plane at 50,000 feet. There is no soot up there, no black bits. Yet that is the beginning of a rain system. As the ice gathers it descends by weight to lower levels and forms rain clouds which eventually drop as downpours. CO2 comes out of volcanoes ejected by each volcanic blast then kept aloft by thermals and upperlevel turbulence. Being heavier than air it all eventually drops back to the ocean, where it is water soluble.
To suggest that soot changes weather patterns is to deny the enormity of the weather systems and to give far more credence to man's tiny tiny impact than is justified. There is no evidence that man-made pollution contributes more to the soot levels in the air than gets there through natural forest and bush fires and perennial eruptions from volcanic sources all around the globe. There is evidence that volcanoes like the Taupo eruption and Pinatubo had slight momentary effect, but that dissipated quickly too. Temperature records from before, during and after Pinatubo show hardly any deviation. This can be easily verified.
Whilst it is true that dust particles form around droplets of rain, barely 100 years ago it was never claimed that soot altered world weather patterns when cities like London, Chicago, Shanghai etc had pea-soup fogs. Cities are now much cleaner than in the past, even in Beijing. As cleaner methods are found to burn coal the level of soot is always diminishing. Of course it is not pleasant to breathe it in, and we can always do more to create cleaner habitats. It is costly, because we all want to live near the places of work and industry emits fumes. To both dwell and work in the same small area demands a lot is spent in cleanup operations for no production return. Who will foot that bill?
In the debate about world weather we tend to forget that rain is really quite local. In Auckland we do not get rain that has travelled from Nebraska. We get rain that came from the Manukau or Waitemata harbours. The cycle of evaporation to rain is about 7 days. Average wind speeds are from 1- 7m/s, or no greater on average than 15mph, or 2,500 miles per week, which is not even the width of China (3,123 miles). Also, when local clouds get rain-laden they often become stationary. Considering that after 7 days most atmospheric soot would have all but dissipated, it is hard to see how loads of soot would make it anywhere beyond Chinese borders in any appreciable amounts and with any significant effect.
Emissions are just dirty steam, mostly water vapour content which just joins the sky as extra cloud. The dirty bits of fuel that give the discolouration are minute and heavier than air particles which fall to ground and are biodegradable. Of course it is not healthy to breathe them in, but breathing any smoke is equally not good for you, for instance the carcinogenic fumes from barbecued sausages, yet no one is saying sausages are wrecking the planet.
Given the vastness of the atmosphere and the huge altitude where weather is generated, some 8 miles from the ground, vs the tiny amount of city smog that only rises a few hundred feet by day then falls again to ground under its own weight at night, it is impossible that weather could ever be affected by it. Remember too that NZ weather comes from thousands of miles across the ocean, either under the Great Australian Bight, up from southern ocean’s icy polar waters or down from the Coral Sea via the Queensland coast, all areas where there are no factories or cars.
No matter how much impurity is put into the air, it is from the earth and so it all has a natural source. None comes in from outer space. No matter how polluting we decide to be, and how much we mess our own living environments, all the people will die off long before the planet itself is affected. Remember, the choice to live in cities, near emissions, is always ours. We must go to work, we need to drive to get there. We need supermarkets for food and they need trucks and highways to keep the shelves stocked. Pollution is simply inevitable. We can choose to wring our hands in despair or get on with life minimalising pollution where we reasonably can.
The Chinese are going through what European cities went through half a century ago, and they are realising that there is a pollution problem to be fixed. But it is a local problem for them only, and only affects us if we choose to go there as tourists or as athletes. Their dirty air may dismay sightseers but it will not destroy Planet Earth. Imagine if cities were once again 100% composed of filth and open sewerage. Such fecal impurities were once called compost. They were described in yesteryear as good for the planet. Whilst no one is advocating a return to filthy city environments we should realise that climate and the earth were here first, then we all came along. We have added no more impurities than have other species. Climate and the earth will still be here when we are all gone.