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Earth Approaching Tipping Point Say Scientists
Hugh Pickens writes "The UC Berkeley News Center reports that a prestigious group of 22 internationally known scientists from around the world is warning that population growth, widespread destruction of natural ecosystems, and climate change may be driving Earth toward an irreversible change in the biosphere, a planet-wide tipping point that would have destructive consequences absent adequate preparation and mitigation. 'It really will be a new world, biologically, at that point,' warns lead author Anthony Barnosky. 'The data suggests that there will be a reduction in biodiversity and severe impacts on much of what we depend on to sustain our quality of life, including, for example, fisheries, agriculture, forest products and clean water. This could happen within just a few generations.' The authors note that studies of small-scale ecosystems show that once 50-90 percent of an area has been altered, the entire ecosystem tips irreversibly into a state far different from the original, in terms of the mix of plant and animal species and their interactions. Humans have already converted about 43 percent of the ice-free land surface of the planet to uses like raising crops and livestock and building cities. This situation typically is accompanied by species extinctions and a loss of biodiversity. 'My view is that humanity is at a crossroads now, where we have to make an active choice,' says Barnosky. 'One choice is to acknowledge these issues and potential consequences and try to guide the future (in a way we want to). The other choice is just to throw up our hands and say, 'Let's just go on as usual and see what happens.'"
It would have been nice if you provided a link or two.
Guns don't kill people; Physics kills people! - John Lithgow as Dick Solomon on Third Rock From The Sun
The report cites "explosive population growth" [citation needed]
http://en.wikipedia.org/wiki/File:World-Population-1800-2100.png would be a start. For your other claims, maybe actually read TFA?
What no? That's only a sign that growth is less than exponential, which shouldn't be surprising at all. That doesn't mean the growth rate is half as fast. Say for example you started with the function f(t)=t^2 and looked at starting at t=1. To double f the first time one needs to go to about 1.4. To again double f one needs to go 2, to double again one needs to go to about 3.8. Here the growth rate is increasing, but the doubling time is also increasing. This is a common pattern for functions which grow more slowly than exponential.
It certainly is peer reviewed. You can see Peter Norvig's analysis of the research. You're just making shit up.
What a fool believes, he sees, no wise man has the power to reason away.
Nonsense
United States area = 9 trillion square meters (approximate)
United states average insolation over 24hrs = 100w (pessimistic)
United States average energy draw all forms of energy = 3.4 trillion watts
Photovoltaic conversion factor = 15% (pessimitistic)
area * insolation * conversion factor = 135 trillion watts average over 24hrs
135 trillion watts > 3.4 trillion watts, even given these wildy pessimistic assumptions.
of course covering the whole of the USA with solar panels is ridiculous, then you have storage to deal with, but yeah, your sums are out by several orders of magnitude.
Actually energy and economics are it. We can make more fresh water and fossil fuels, and thus more food, if we have enough energy and the will to do it. (And we can even turn waste into fossil fuel at a "net energy gain." (As opposed to just throwing the waste away that is.))
You're right that anything that grows will exhaust its resources but you're missing two key points. First, humans tend to expand the amount of resources at their disposal through new technology. Second, in general the first world is no longer experiencing population growth.
It is thus conceivable that we could expand our resources enough to get everyone up to a first world standard of living and thereby achieve a steady state population. I'm not saying this will be easy, just that disaster is not foreordained. (Well, outside the heat death of the universe anyways, but we might even figure that one out if we last long enough =)
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