Scenario 8: World Seeks Stable Population and Stable Industrial Output per Person from 2002
If the model society both adopts a desired family size of 2 children and sets a fixed goal for industrial output per capita, it can extend somewhat the “golden period” of fairly high human welfare between 2020 and 2040 in Scenario 7. But pollution increasingly stresses agricultural resources. Per capita food production declines, eventually bringing down life expectancy and population.

Scenario 1: A Reference Point
The world society proceeds in a traditional manner without any major deviation from the policies pur-
sued during most of the twentieth century. Population and production increase until growth is halted by
increasingly inaccessible nonrenewable resources. Ever more investment is required to maintain resource
flows. Finally, lack of investment funds in the other sectors of the economy leads to declining output of
both industrial goods and services. As they fall, food and health services are reduced, decreasing life
expectancy and raising average death rates.

Scenario 1, show the behavior of World3 when it is run “as is,” with numbers we consider a “realistic” description of the situation as it appeared on average during the latter part of the twentieth century, with no unusual technical or policy assumptions. In 1972 we called it the “standard run.” We did not consider it to be the most probable future, and we certainly didn’t present it as a prediction. It was just a place to start, a base for comparison.

In Scenario 1 the society proceeds along a very traditional path as long as possible without major policy change. It traces the broad outline of history as we know it throughout the twentieth century. The output of food, industrial goods, and social services increases in response to obvious needs and subject to the availability of capital. There is no extraordinary effort,beyond what makes immediate economic sense, to abate pollution, conserve resources, or protect the land.

The population in Scenario 1 rises from 1.6 billion in the simulated year 1900 to 6 billion in the year 2000 and more than 7 billion by 2030. Total industrial output expands by a factor of almost 30 between 1900 and 2000 and then by 10 percent more by 2020.

Then suddenly, a few decades into the twenty-first century, the growth
of the economy stops and reverses rather abruptly. This discontinuation of past growth trends is principally caused by rapidly increasing costs of non-renewable resources.

In the simulated year 2000, the nonrenewable resources remaining in the ground would have lasted 60 years at the year-2000 consumption rate. No serious resource limits are then in evidence. But by 2020 the remaining resources constitute only a 30-year supply

During those two decades in Scenario 1, the growing population and
industrial plant use nearly the same amount of nonrenewable resources as the global economy used in the entire century before!

This scenario portrays a “nonrenewable resource crisis.” It is not a prediction. It is not meant to forecast precise values of any of the model variables, nor the exact timing of events. We do not believe it represents the most likely “real world” outcome.

The strongest statement we can make about Scenario 1 is that it portrays the likely general behavior mode of the system, if the policies that influence economic growth and population growth in the future are similar to those that dominated the last part of the twentieth century, if technologies and values continue to evolve in a manner representative of that era, and if the uncertain numbers in the model are roughly correct.

Polycrisis and Systemic Risk: Assessment, Governance, and Communication

The emphasis of integrated disaster and risk research has shifted from topical analysis, such as dealing with natural hazard-related disasters, technological accidents, or environmental crises, to a comprehensive analysis of interconnected and mutually interactive risk sources and crises.

This interaction has often been framed in the language of “polycrisis” indicating the potentially amplifying and cascading effects of each crisis from one domain to the next. At the same time, the literature on systemic risk also includes the effects of multiple, interacting risks on the functionality and survivability of entire systems such as climate stability, cybersecurity, or energy production.

This review article provides first a summary of the literature on both concepts, explicates the commonalities and differences and develops a risk and crisis concept that builds a bridge between the two research traditions. Based on this concept, the review delineates the implementations of a joint understanding of polycrisis and systemic risk for risk assessment, risk and crisis governance, and effective communication to different audiences.