Actually the carrying capacity hasnt changed that much (as evidenced by the impact on said environment) certainly it is non static, but it isnt dependant on our technology so much as we might like to think
Modern humans have been on this planet for 10s of thousands of years. For the bulk of that time, modern carrying capacities were nothing compared to what are now.
"The primary importance of dating methods in archaeology is in analyzing cultural changes. To take an example, some have argued (chapter 6) that people first domesticated sheep and goats and began farming wheat and barley in the Middle East
because human population densities had risen to the point that people could no longer survive on hunting and gathering alone. Other people suggest that rising population densities had little to do directly with the origins of agriculture in this area."
Wenke, R. J., & Olszewski, D. (2007).
Patterns in prehistory: humankind's first three million years (5th ed.). Oxford: Oxford University Press.
"To compensate for this, between about 11,000 and 10,000 years ago, the peoples of the Fertile Crescent initiated a process of cultivation and artificial selection. They planted seeds of wild cereal varieties, such as einkorn and emmer (both ancient types of wheat), that retained their seeds most effectively during harvesting and that bore those seeds in concentrated clusters. The earliest grain cultivators would also have applied another level of selection by planting the seeds of the most vigorous and productive individuals of their preferred species. At first, such planting was done to supplement the gathering of wild cereals, and only later would it have become a mainstay.
The radical innovation in human economic and social existence that this development heralded may well have been spurred by climatic change, but it was made possible by the convergence of a number of unrelated factors that must have included social and technological innovations, as well as the availability in the local environment of species suitable for domestication.
Wheat was soon joined as a cultivated crop in the Fertile Crescent by barley and by legumes such as lentils and chickpeas. Just a few miles north of the better-known Neolithic site of Jericho, in the Jordan Valley, lies what remains of Netiv Hagdud, a farming village that was occupied between about 9,800 and 9,500 years ago. Excavated in the 1980s, Netiv Hagdud provides a unique glimpse of the very beginnings of farming in the Fertile Crescent. The site covers about four acres and preserves the floors and foundations of a number of square and oval mud-brick houses.
It is hard to know exactly how these structures were used by their inhabitants, but it is estimated that the village housed some twenty to thirty families, a total of between 100 and 200 people. This would make Netiv Hagdud about average in size for the time, with a population about half that of Jericho but considerably larger than that of some other contemporaneous settlements."
pp. 110-111
Tattersall, I. (2008).
The world from beginnings to 4000 BCE. Oxford University Press.
because we do not even really attempt to address the negative externalities of human existence which are borne by the environment
This is impossible, as we are part of the environment. The environment is in constant flux and always has been. The most radical change occurred billions and billions of years before humans existed. Sometimes I wonder how much of some environmental thinking is just a distorted sense of human importance. There is no delicate balance and never has been. Most species that ever existed are extinct, the most devastating destruction of life this planet has seen was before humans existed, and if we dump gallons upon gallons of waste into rivers, dump nuclear waste wherever we want, and burn coal just for the heck of it, we'll kill off ecosystems like there was no tomorrow and probably all die, and it would be nothing that hasn't happened before.
the carrying capacity really is subject to those negative externalities
This planet is a network of complex systems far from thermodynamic equilibrium. If it were that delicate, life wouldn't exist. Chaotic systems like earth fluctuate wildly within certain bounds. Changes, even drastic changes, don't do much most of the time. Climate change originated when the version of "chaos theory" called catastrophe theory (now "dynamical systems" or "complex systems") was in vogue. The focus has shifted from the emphasis on phase space changes catastrophe theory had, but criticality still exists. Lots of little changes can still result in an avalanche. The problem is not externalities as some ecosystems depend upon human development now just as much as others are being destroyed by it. The problem is knowing what changes are doing what. And we don't know, despite the arbitrary rise in a 5% confidence by the latest idiocy out of that political disaster we call the IPCC. They're are only slightly more scientific than the NIPCC. Are humans warming the planet? Almost certainly yes. Are they doing so to a dangerous degree? Again almost certainly yes. Should things be done, like investing in green energy? Even if humans weren't warming the planet, again yes. Are we trusting political summaries too much? Well, don't take my word for it:
A very grand challenge for the science of climate prediction
See also:
From the INI's
Mathematical and Statistical Approaches to Climate Modelling and Prediction, "
After Climategate and Cancun; What Next for Climate Science?"
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