[geo] Geoengineering for emergency braking

[John Nissen]

Hi all, I've a simple picture of the situation.  Think of the Earth system as a bus, with automatic speed control mechanism to keep the bus between two speeds - a top speed and a bottom speed.  When the bus gets to the top speed the brakes automatically come on and the throttle starts closing.  Then when it has slowed to the bottom speed the brakes automatically come off and the throttle starts opening again.  This mechanism has worked for over a million years, keeping the bus running between higher and lower speeds, without the driver doing anything.  [Global temperature has oscillated between a top and bottom temperature over the course of the Ice Ages.  The Arctic sea ice is probably involved in preventing the temperature going above the top limit.  CO2 may be involved in preventing the temperature going below the bottom limit.] Then, about 8000 years ago, when the bus was near its top speed, the driver took over control.  Although the brakes were starting to come on, the throttle was kept open by the driver by just the right amount to keep the bus going at the higher speed.  This kept the passengers extremely happy!  They thought this situation would carry on for ever, but this proved to be wishful thinking. [By amazing chance, mankind's inadvertent emissions of CO2 and methane have kept global temperature, and hence sea level, pretty constant for about 8000 years, thus allowing the emergence of civilisation.] Then suddenly, a hundred years ago, the driver started opening the throttle more than it had ever been before, whilst at the same time taking off the break.   Surprise, surprise, the bus started to accelerate.  Some passengers refused to see the danger - they were enjoying the speed, and were happy for the driver to open the throttle even more.  Other passengers saw the danger.  The passengers broke into argument, and eventually agreed on a compromise to gradually stop opening the throttle, although it was realised the bus could reach a dangerous speed. [Mankind has injected a colossal pulse of CO2 in the atmosphere, which continues to grow, and will continue to grow under any Copenhagen agreement.  Global warming is an inevitable consequence of the excess CO2 (although other gases contribute, both positively and negatively).] Nobody wanted to point out that, at this speed, the bus would become unstable and almost certainly crash off the road putting everybody's life at risk.  Thus it was actually in everybody's interest to close the throttle and apply the brakes straight away.  The compromise they had reached just gave a false sense of security. [Nobody seems willing to point out that our present path, akin to business as usual, could lead to the collapse of our civilisation, e.g. through famine.  Any deal at Copenhagen is liable to engender a false sense of security.] Soon after the compromise had been reached, the bus, already travelling dangerously fast, skidded on some ice, which the driver saw too late, hit a tree and burst into flames, killing all on board.  [Tipping points have been ignored.  The Arctic sea ice could disappear quite rapidly, with potentially lethal consequences from methane release and/or Greenland ice sheet disintegration.  The Amazon rainforest is also at risk of drought, leading to die off and burn.] Sadly this fate was not inevitable.  Unknown to the driver, there were emergency brakes that could have slowed the bus, even while the throttle was open.  But the driver had been told that these emergency brakes were too dangerous to use, so was not prepared to use them.  When he saw the ice, he tried to apply the emergency brakes but it was too late. [The only reasonable chance of saving the Arctic sea ice is through the application of geoengineering to cool the region.  The chance of geoengineering successfully diminishes as positive feedbacks build up in the Arctic.  The more we delay geoengineering, the more we risk passing a point of no return, so that a gruesome fate becomes inevitable, possibly even for most people alive today.] Cheers, John -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to geoengineer...@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en.