They created a detailed baseline projection of a more urban world population and then had two alternate scenarios. Then they created narrative stories that considered conflicts within the baseline or alternate projections.
They projected demographics and then they projected technology.
The alternate scenarios are
* a world of water scarcity
* a world where China and India are near peers of the United States in economic and military power
Nextbigfuture was one of many references used in the US Marine study
Standard Chartered economic projection to 2030
I do not think India will do quite as well as the Standard Chartered projection. 2016 update, China will likely underperform a 6.9% average to about 5.0-6.0% average through 2030.
In 2030, I think Canada with a population of about 44 million and South Korea with about 53 million could be in the bottom of the top ten economies or very close. South Korea could also re-unify with North Korea by 2030.
Projected 2030 economies can easily vary by plus 20% or minus 50% depending upon some country having a lot more problems or very good luck and policies. There is less margin of error for the developed countries like the US, Japan, and Europe
Even with those margin of error levels.
China's economy should be the world's largest by a comfortable margin and possibly twice as big as the USA or India. (50-90 trillion)
India and the USA and the EU-27 should be in the range of the same size in the next tier. (around 20-40 trillion)
Japan, Germany, UK, France, Indonesia, Brazil, Russia, South Korea and Canada will be in the third level. (around 5-10 trillion)
The nomimal GDP forecast is highly dependent upon the exchange rate. Currently the Chinese yuan is weaker. The 2020 projection is now that China will have about US$15-17 trillion and the US about $25 trillion. The new IMF has some inflation included compared to the prior projection.
By 2030, the balance of economic power will have shifted from the West to the East: while the US, the EU and Japan represented 72% of the global economy in 2000, their share should shrink to only 29% by 2030 – a complete reversal of their importance relative to the emerging world.
By 2030 we assume the CNY will have appreciated from 6.64 this year to 4.39, and the INR from 45.5 this year to 35 in 2030.
Growth projected in 2012
We see the US economy growing 2.6% in 2010, only 1.9% in 2011 and 2.7% in 2012, then growing at a stronger pace, with trend growth of 2.5% over the horizon to 2030. Likewise, we see the EU-27 growing 1.8% in 2010, 1.7% in 2011 and 2.2% in 2012, reflecting a sluggish recovery from the crisis, with large output gaps and stubborn unemployment. Over the forecast horizon to 2030, the EU-27 is expected to grow at its trend growth rate of 2.5%. For Japan, the growth figures are 1.5% (2010), 1.0% (2011) and just under 2.0% (2012), and 1.0% over the forecast horizon to 2030.
China’s growth rate is forecast at 10.0% (2010), 8.5% (2011) and 8.0% (2012), averaging 6.9% over the two decades to 2030. For India, the growth figures are higher, at 8.1% (2010), 8.5% (2011) and 8.8% (2012), averaging 9.3% over the forecast horizon. When one considers these figures, it is clear we have assumed a very fragile recovery from this crisis in the West, and trend growth rates that are not exaggerated for emerging economies, using China and India as examples. For instance, there are credible arguments that India may even achieve a trend growth rate nearer 12% or so, with certain conditions in place.
In 2017, China needs to be in the 5-6% GDP growth range average and with a weaker currency. India is average 7 to 8% GDP growth with a weaker currency
China should just ahead of the US in economic size in 2030 or about the same size.
India will still be lagging but should be third and larger than Japan.