by MonteQuest » Sun 10 Jan 2016, 23:35:11
$this->bbcode_second_pass_quote('jesus_of_suburbia', ' ')Are we going to see a populations higher or lower than those projected?
You're saying they are underestimating, then saying we are going to hit limits. I'd think that if we are hitting limits we won't see even those lower end projections. The die off will see that we won't come close to those.
Unless you're saying that we are going to hit the higher projects mid to late century then have a harder population crash?
I am saying I think those projections are too low for the years depicted. If demographic transition doesn't happen, then the TFR (total fertility rate) won't decline, and the world's population will grow at a faster pace. At our current growth rate of 1.14%, using the Rule of 70, 70/1.14 = 61.4 yrs until the current population doubles to 14.7 billion. That's 2077.
At that growth rate in 2030, we will have 8.5 billion. UN projects 8.5 billion
In 2050 10.7 billion. The UN projects 9.7 billion in 2050.
In 2100 18.9 billion. UN projects 11.2 billion.
So, you can see that the population is going to continue growing at 1.14% for the next 14 yrs due to population momentum even if the TFR falls by 2030. There is a lag time.
The lower numbers the UN projects assumes the TFR is going to continue to fall as the developing world urbanizes and sees a rise in their standard of living. The UN expects global fertility to drop from the current average of 2.5 children per woman to 2 children per woman by the end of the century. But these reductions aren’t going to just happen on their own. Demographic Transition must take place or a massive global investment (Manhattan Style Project) in family planning and reproductive health. If fertility rates are only half a child per woman over the rates expected, the population will reach 16.6 billion by 2100.
Even the UN doesn't see a peaking or leveling out of the world's population this century. Even at ZPG, 2 children/woman by the end of the century, due to population momentum, the world's population will continue to grow for another 50 to 75 years, albeit at a much slower rate.
I'm saying the growth rate isn't going to slow like they project, and we are going to have more people sooner.
Now, as to what number we might reach before there is a "correction" or die-off, I don't know. We might not see 8 billion, given we need to double food production by 2050. But consider that many Pherologists estimate the earth can support 3 billion on a sustainable basis, maybe more, maybe less. We are in severe Overshoot supported only by fossil fuels and they are going away.
Bottom line: We will all need to learn to share and/or fight over the remaining resources.
A Saudi saying, "My father rode a camel. I drive a car. My son flies a jet-plane. His son will ride a camel."