Climate Change (specifically global warming) is a scary and mostly destructive reality, as far as human concerns go. The extent to which human activity is involved in climate change is, in some circles, debatable; but the balance of science suggests that human industrial activity, specifically the burning of fossil fuels, produces the so-called greenhouse gases, such as carbon dioxide, which trap solar radiation and geothermal heat that would have otherwise radiated into space, thus on average increasing global temperatures. Ergo, it seems likely that human endeavours play a large part in the changes we are witnessing.
Thus endeth the science recap.
To be honest, I don’t live a very green-conscious lifestyle. My experience with most recycling programmes is that the separated items just get recombined later and my work ends up having been wasted. I buy whatever is cheapest, not necessarily whatever is most politically appropriate. And I reason that having ridden bicycles and walked all my life, I am now entitled to a little solitary car driving now that I’m almost middle aged and newly a driver. I believe the only true solutions to the greenhouse crisis will be effected at the industrial and organizational levels, not at the personal level. Am I rationalizing? Most definitely. But there it is.
I support nuclear power as an alternative to coal and oil burning. I thus also support the eventual conversion of most automobiles to electric engines, recharged via electricity produced in nuclear, geothermal and hydroelectric plants. I think calls for conservation as a long term solution are naive; human society will require more energy, not less, regardless of how much conservation we manage to enforce. The increasing electrification of the Third World and an ironically green-friendly global shift from paper-based offices to computer-based information networks indicate a rocketing need for more power in the near future.
And no matter how many gas-burning cars we manage to eliminate, the overall impact on atmospheric carbon production will be negligible so long as we rely upon gas-burning airplanes for international travel. I have no solution for that problem, and I don’t think the global economy can survive a loss of air travel. But there is one variable I do wish to address: space flight.
Many people believe that rockets and space shuttles spew more carbon into the air with a single launch than do a thousand cars. The truth is that, for the most part, spacefaring rockets “burn” a combination of liquid hydrogen and liquid oxygen –the byproduct of which is water. Ironically, releasing so much water high into the atmosphere is proving to have its own negative environmental consequences, having to do with affecting the ozone layer and having nothing to do with greenhouse gases.
Might I suggest, however, that if low orbital space flight can be made cleaner and safer, it may prove to be an effective, economical and environmentally friendlier alternative to basic air travel. Several designs for such vehicles have already been proposed, some employing revolutionary scramjet technology for when such a craft re-enters the thin high atmosphere.
In the long term, cleaner, safer and cheaper alternatives need to be employed for launching payloads into low and high orbits. A while back, the orbital tether –an idea that’s been around for 100 years– was actually discussed in the news. We are nowhere near having the materials or construction technologies necessary to build one.
But we do have the materials needed to build a mass driver. I strongly suspect that some enterprising government or corporation will endeavour to build a mass driver –essentially a rail gun powerful enough to shoot things into space– sometime in my lifetime. And basic physics suggests that it will be built near the equator, on the side of a mountain with a large body of water immediately to the east. Maybe I should start soliciting geographical guesses now? Any takers?