Is geoengineering a viable solution to climate change?

With climate change a real and increasing threat, scientists are coming up with more and more bizarre methods of prevention or reversal. Amongst those cited in an article in The Guardian are

• putting 1.9 million tonnes of cooling sulphur into the atmosphere, via ballooons;
• placing iron particles in the ocean to increase carbon-absorbing phytoplankton, a form of marine carbon sequestration;
• using large tubes which will move vertically with waves and pump cooler water and nutrients to the ocean's surface and encourage the growth of phytoplankton;
• using giant platforms to re-ice the Arctic by spraying salty water onto ice, thereby increasing its thickness and preventing an onslaught of fresh water when the ice melts in summer, in effect maintaining the threatened Gulf Stream;
• placing light refractors between the earth and the sun to reflect some of the sun's rays back into space. (Far out!)
  

Freaky? I think so. But perhaps not as freaky as the alternative. Let's hope it doesn't come to that. For the full story see http://www.guardian.co.uk/technology/2008/may/29/greentech.geoengineering

Whilst we're on the subject of climate change, one of my favourite topics has raised its head again: the environmental impact of aviation, that is can flying ever be "green"? The London Science Museum is housing an exhibition titled "Does flying cost the Earth?" until November. It looks at the effect flight has on climate change and the new technologies being considered by the aviation industry in an attempt to green up aeroplanes and keep the industry going in a world increasingly concerned by CO2 emissions. I wish I could go. This is one of the things I miss about London. Would someone please go on my behalf and report back?

Coincidentally, perhaps, next week is World Environment Day and the University is hosting the Sunshine Coast World Environment Day festival this Saturday. I had intended to be really green and go along on my bike but a couple of things are putting me off. Firstly, I have recently been suffering from a really sore back following lengthy bike rides, which is a bit annoying as I have been quite enjoying my rides to work. Secondly, the weather is going to be rubbish, otherwise I'd walk. It's only 7.5 km which would be quite pleasant on a nice day. On a rotten minging day, however, it would be very unpleasant so I'll either take the bus or, more likely, drive. If I do make it there, and it's interesting, I shall endeavour to report back next week.