World Population Growth

The (human) carrying capacity of Earth was estimated to be around 2 billion, which was surpased sometime in the late 1920's. Contrary to other comments here, that does not mean that after you hit population 2,000,000,0001 we all die (we clearly did not). Instead, what it means is that given the technological level we had at that time, we'd consume renewable resourses faster than they can renew themselves, and we'd also produce waste faster than the environment can degrade it. Otherwise, more than 2B people would cause environmental degradation, which would itself reduce the carrying capacity in the long term.

Please note this definition is tied with humans technological level. It is not set in stone, since we have some degree of control over our impact in the environment, and we have the ability to use the same resources in a more efficient way. The big tragedy of 20th century is that this fact was not recognized but for a handful of theorists, and therefore it was not a political and economic goal to explicitly manage the carrying capacity of Earth. As of 2016, the situation is still the same.

By example, we gained a bunch of technologies that allows us to do the same stuff more efficiently. Given explicit economic incentives, we might have... maybe doubled our carrying capacity (CC=4B). Unfortunatelly, because this was not a goal itself, we engaged in a buch of economic practices that negated much of this benefits, so if we are generous these might have been reduced by half (e.g. CC=3B). Also given that population growth was not arrested back in the 1970's, but only slowed down, the carrying capacity has not improved at all (CC=2B).

Currently, environmental degradation is going in overdrive. We have lost a lot of time, and the resources we need to make an orderly transition are already commited to keep the system going. Population will go down, one way or the other. I don't believe in a single sharp die off many apocalyptic thinkers profetize, but adding and extra 1.6B mouths to feed will make the downward tendency of the curve more steeper than it needs to be.

But there many studies that claim carrying capacity is much higher than current population, and that the projected 16 billion simultaneous living humans is within capacity.

It seems like whether we have a soft landing at the end of the oil age could dominate any calculation. The ability of renewables to scale up is only just crept past the starting line of a long, but necessarily urgent race. I'm not very enthusiastic about the odds.

You mean due to the process discovered by Fritz Haber.

It isn't the case that if he hadn't discovered the process in 1909 that in 2016 the human species would still be without it.

2. the heat indices of that country can be quite astonishing