The main topics discussed on this blog are the major fiscal and economic issues facing the U.S. My approach is to be calm, factual, rational and objective but I do have a very definite point of view. I am an optimist. I think that life is getting better slowly but surely both in the U.S. and around the world, see here and here.
The key to this progress is economic growth. Faster growth means more progress. But there are limits as to how fast the economy can grow. In particular there are environmental limits as I have discussed in my last two posts, here and here.
Global warming is definitely a huge threat to human progress.
But severe overpopulation is not likely based on two reliable sources which I am using. One is the latest UN Report, “World Population Prospects, 2017”. The other is the 2010 book by Matt Ridley, “The Rational Optimist”.
World population in 2017 is 7.6 billion. 10 years ago it was growing by 1.24% per year, today it is growing by 1.10% per year, i.e. growth is slowing down.
There is a 27% chance that world population will stabilize and begin to fall before the end of this century (see graph). Mr. Ridley’s prediction that population will peak at 9.2 billion in about 2075 and then begin to fall is consistent with the lower level of the UN graph.
The UN’s median projection is that the global fertility level will decline from 2.5 births per woman in 2010-2015 to 2.2 births per woman in 2045-2050 and then to 2.0 births per woman in 2095-2100. Since replacement level is 2.1 births per woman, no later than 2100 the die will be cast for world population to peak in the early 22nd century and then begin to decline.
Already 83 countries in 2010-2015 had below replacement level fertility. After 2050 Africa will be the only region still experiencing substantial population growth.
Conclusion. Sometime between about 2075 and the early 2100s, world population will peak and then begin to decline. The sooner this happens, the less misery there will be for humanity. Nevertheless, the catastrophe of never ending population growth is very unlikely to occur.
Human civilization has made remarkable progress in the past two hundred years starting with the Industrial Revolution. This has been well documented in two current books, The Rational Optimist by Matt Ridley and Progress: ten reasons to look forward to the future by Johan Norberg.
But for human progress to continue indefinitely into the future depends on sufficient economic growth. Faster growth means more progress. The purpose of the Republican tax plan now working its way through Congress is to speed up economic growth in the U.S.
It is a legitimate question to ask whether there are environmental constraints on faster growth. What are the world’s largest environmental problems and how serious are they? In rough order of severity:
Global warming is a very serious problem, for which the evidence is overwhelming. The use of renewable energy sources like wind and solar is growing but not fast enough to stop the world wide increase in carbon emissions. It will require the world’s two largest economies, the U.S. and China, working together to solve this huge problem but it can be done.
World population is likely to stabilize at about 9.2 billion (the Rational Optimist, page 206) by 2075 and then start to decline. This is because in country after country economic progress has led first to slower mortality rates and then to slower birth rates. When this demographic process eventually reaches Africa, world population will begin to decline.
Pollution is on the decline around the world (see above chart from Norberg). Air pollution is declining in the U.S. (see Ridley, page 279) and China is beginning to get serious about it.
Natural resources are simply not running out, see here and here.
Conclusion. Yes, the world has environmental problems (mainly global warming) but no, they need not stand in the way of economic growth indefinitely into the future.