In this new scenario, it is thus postulated to spend more money on increasing the efficiency of use of the remaining natural resources.
References:
In order to accomplish this change, you need to modify the table P_Res_Tech_Chg_Mlt_NRCM that models a multiplier to the investment in technology to increase resource use efficiency:
parameter Real p_res_tech_chg_mlt[:] = {-0.04,-0.04,0,0} "Resource technology change multiplier";.
Simulate the model from 1900 until 2100, and display the same variables as in the book Limits to Growth: The 30-Year Update at page 219:
This seems to have done the trick. The population no longer declines during the 21st century. Is this effort sustainable?
To answer this question, let us simulate the model once more, this time from 1900 until 2500:
The effort is indeed sustainable. The world population hovers around 10 billion people. Yet, these people live very poorly. In the end, no money is left for industrial production and/or services. All of the human efforts are spent on feeding the world population in a sustainable fashion. The life expectancy is back at its pre-industrial value of 27.6 years.
No generation before ours lived as long and as prosperous as we do, and the likelihood is large that none coming after us will do so either.