While on my exercise bike, I listed to a Counterpoint podcast called Population and Environment. In this podcast, Mark O'Connor claims that Australia is overpopulated and action needs to be taken to reduce population in Australia by reducing immigration and birth rate. I think there are problems with reducing immigration and birth rate.
If we look at carbon dioxide emissions, reducing immigration, I doubt, will have much effect on global carbon emissions. Suppose an American comes to Australia, purchases a car, and drives it. By driving he is producing pollution in the form of carbon dioxide emissions. However, had this individual stayed in America instead of coming to Australia, who is to say that this individual wouldn't have driven around in a car in America and caused the same problem? Some people, e.g. Ross Gittens, argues that people move from one place to another to better their lives, and by doing so they must increase the degree to which they pollute. For example, the individual in my example may be unemployed in America and hence he stays home and does nothing, which means he is environmentally friendly. However, once he gets a job offer in Australia, he travels here, spews jet emissions, and then spews even more carbon emissions once he drives to and from work in his car. This is a fair argument. Free immigration increases the potential for economic growth, which in turn increases pollution because trade usually involves energy consumption of some kind. However, we have now a tricky trade-off between environment and economy. Suppose that environment is more important than economy. We could achieve the same economic inefficiency simply by increasing taxes or by implementing an emissions trading scheme. Blocking immigration may even be both economically and environmentally inefficient if it blocks the transfer of knowledge and skills related to environmental productivity. For example, suppose that BHP Billiton in Australia wants to reduce emissions from its mining operations. Suppose also that in a Japanese university there is an scientist there who knows how to reduce emissions using some technology. BHP wants to hire this scientist but because immigration is banned, the scientist cannot come to Australia and BHP cannot implement green technology into its business. This means that BHP is not able to be as green as it wants to be.
O'Connor also claims that Australia ought to reduce natural population growth by getting rid of the Baby Bonus. An idea would be to introduce a tax on childbirth. I believe that lower birth rate can be achieved simply by taxing energy or by establishing an emissions trading scheme. A child costs approximately $250,000 to raise from birth till 18. When a couple wants to have a baby and believes that it has the ability to produce $250,000 over the next 18 years, the couple will have a baby. However, suppose a cap-and-trade scheme is implemented. This should raise the price of energy, which means the cost of having a baby should also increase, say, from $250,000 to $300,000. An increase in the cost of having a baby should decrease birth rate.
Applying a global tax on energy or a global emissions trading scheme will reduce carbon emissions. However, many poor people will not be able to cope with the higher costs of energy, and that is why I suggest a global redistribution system.
According to someone at Sustainable Population Australia, there are more problems that high population creates behind carbon emissions (see "Overloading Australia" Author Gets Opinion Piece in The Advertiser): "Mark pointed out that many of the environmental problems we face in Australia today - including water shortages, unaffordable housing, excessive greenhouse gas emission - are all linked to excess population."
Water shortage is not a problem. If there is a lack of water in Australia, we can simply import water (see Australia Could Import Water from Japan). Currently Australia has more than enough coal, oil, and food to feed its population, but currently about 54 per cent of Australia's exports are food, minerals, or energy. Because of global trade, shortage of food, energy, or minerals is not really an Australian problem. Rather, it is a global problem. When there is a scarcity of some good, there is a tendency for technology to improve to take advantage of the high prices from scarcity. If oil prices climb very high because of increasing scarcity, technology may improve to find alternative sources of energy. Of course, it is possible for humans to find no technology to fix problems of water and oil scarcity. It is possible, I think, for humans to live without oil, but it is not possible for humans to live without water. If there is finite water then we will have no choice but to all die. The human race will be wiped out eventually. In reality, clean water comes from rivers and streams after it has been filtered through rock, etc. Water can even be filtered using machines.
Another problem mentioned at SPA is unaffordable housing. This problem I believe is easily fixed. Suppose we have a fixed number of house and all of a sudden we have a surge in population. We have more people bidding for the same amount of houses, so obviously the price of houses goes up. This problem can easily be fixed simply by increasing the number of houses available. This can be achieved by reducing barriers that are imposed currently on property developers, including complex zoning laws, urban limits, etc. One of the reason why American property is so cheap at the moment is because there are so many houses there that have been abandoned after the 2007 residential real estate crash.