Part of the show How many people can Earth support?
Steve Davis asked:
I frequently wonder where we are heading as a species and see the one big issue we continue to ignore is sustainable human population.
I've heard that the Earth can support about 2 to 3 billion people comfortably and sustainably but I don't have a source other than the internet for this figure. Is there any information you can share on this subject?
To shrink the population even over say 100 years is going to be tricky, we'd have to invent a whole new financial model to name just one drama.
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Warneet Australia (Google Earth it and be envious)
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I have long thought that a 5% tax refund for parenting a first child sounds good, and 10% for the second - parents are great!
One of the problems is that the population, as well as the population growth is not distributed evenly around the globe, and some of the highest growth regions are also the least sustainable.
You can calculate the optimum population if you start with a quantifed and reasonably universal measure of standard of living. The simplest is, I think, access to "artificial" energy - gas, electricity, vehicle fuels, etc.
Of course, not all food stuff can be cultivated with the same amount of calories or gallons of water per acre.
Eee! Did a shiver of Soylent Green run up anybody elses spine just then?
I personally think that the stresses the world is under due to over population will be resolved through technology..
You missed the point.. Greed makes doctors ask for money to save peoples lives, above and beyond what they need to live and bring up a family, making the poorest poorer and (because they are poor) more likely to need to go back to the doctor in the future. (yes not all doctors but are you getting my drift?)
Good thoughts, and by no means do I say my examples are the answer to anything.. I dont have the mental capacity to point to the specific solution (otherwise I would be a millionaire..).. I just point out options that exist..
The policy seems to be to strip as many resources now, and leave the next generation to fend for themselves.
We keep burning our boats and relying on future technological advance to get us out of a tight fix, but there is no guarantee that it will. Nuclear fusion may save the day if we're lucky - we'll then be able to grow vast amounts of food indoors. We may also be able to grow artificial meat in vats using as little energy as growing vegetables and fruit, but we're not there yet. Many proposed solutions will not work - irrigating deserts tends to bring salt to the surface and that kills the crops, though genetic engeneering may produce new varieties of crops that can tolerate this. Creating useful amounts of land from the seabed would be a nightmare involving enormous amounts of concrete, and it would be at threat all the time from sea-level rise. Cutting down forests to grow crops is also not wise - we've done too much of that already. However, there is enough food for us all at the moment - all we need to do is stop wealthy people destroying their health by stuffing themselves with unhealthy food like beef so that it can be distributed more fairly, though it would be even better if people switched over to meats like chicken which can be produced for 1/6 of the energy.
One of the problem with "Fusion" power is that while everyone wishes that it could use simple hydrogen 1H of which we have an abundance in the oceans. However, I believe all current tests use much rarer isotopes such as 2H, 3H, 3He, & Lithium.