[ExI] peak fossil by 2020

[Eugen Leitl]

On Fri, Mar 29, 2013 at 04:41:18PM +0000, Tom Nowell wrote:

> Looking at carrying capacity - apparently after the Black Death in the 14th century (which followed a few decades after a huge famine) the global population was estimated at 370 million, so we know the earth can carry that much even when Nature does its best to kill us.

100 Mpeople seems to be a sustainable population at hunter-gatherer level of technology
(which is the likely level after a delayed population rebound after a total nuclear 
exchange, especially if records are unreadable due too much magic).

The exact figure doesn't matter that much.
 
> According to the UN's figures at http://www.un.org/esa/population/publications/sixbillion/sixbilpart1.pdf
> world population reached 1 billion in 1804, which is 6 years after Malthus predicted a grim future ahead. So, even with 1800-era technology 1 billion seemed manageable.

Malthus failed because he didn't anticipate shift from biofuels to fossil,
and Liebig (artificial fertilizer). 1800-level of technology wasn't
sustainable already. It's just that their burn rate was slow enough.
 
> On the one hand, we do have genetic engineering and a big variety of seedstocks available, and even if only a small amount of petroleum is available we could still make a small amount of pesticides, so we could keep more people fed with limited resources.

Genetic engineering is a high-technology item. It also can't do a damn
thing about thermodynamics.
 
> On the other hand, distribution is always a problem. If we can't get the food from where it's grown to where the hungry people are without the fuel for it, or can't get the supplies needed to the farmers because we don't have the fuel, then the system is screwed. Look at the Ethiopian highlands or poverty in Afghanistan - there may be enough food available across the entire country, but transporting it to the poorest and making sure everyone can avoid malnutrition is a severe challenge to us in 2013.

It's not just a physical layer problem, it's a supernode control
problem. People in power will intercept and resell, so your deliveries
will never reach the recipients. Even if they did, warlords could
confiscate them.
 
> Spike makes a good point about concentrations of population on the coast - back in the Roman Empire, there were huge megacities like Rome and Byzantium fed by shipping in food from grain-rich areas, and huge trade networks. During the last years of Empire as it was collapsing, people fled the cities for rural areas for many reasons, but food security was a big one. The medieval solution of a largely rural society with peasants owing taxes and military service to a noble class of trained warriors, and with centres of civilisation being small,fortified towns with nearby castles, makes perfect sense as a response to the collapse of the Roman world and the threat of invasion.
> 
>  If our society proves unable to sustain itself, will we rebuild like this? Or will be like some of the early North American civilisations who built large settlements and then abandoned them for a different way of life when their climate changed?

It's fun to think about how things turn out if we screw up,
but let's rather think about how not to screw up.