This model simulates the growth of carp in an aquaculture pond, both with respect to production and environmental effects.

 Carp are mainly cultivated in Asia and Europe, and contribute to the world food supply.

Aquaculture currently produces sixty million tonnes of fish and shellfish every year. In 2011, aquaculture production overtook wild fisheries for human consumption.

This paradigm shift last occurred in the Neolithic period, ten thousand years ago, when agriculture displaced hunter-gatherers as a source of human food.

Aquaculture is here to stay, and wild fish capture (fishing) will never again exceed cultivation.

Recreational fishing will remain a human activity, just as hunting still is, after ten thousand years - but it won't be a major source of food from the seas.

The best way to preserve wild fish is not to fish them.

Causal loop diagram capturing the interactions, trade-offs, and synergies between agriculture (SDG 2), water availability (SDG 6), economic growth (SDG 8), and life on land (SDG 15). Positive feedback linkages are shown as a positive sign (+), whereas negative feedback linkages are shown with a negative sign (−). The purple arrows indicate the enviro-biophysical linkages. The green arrows indicate the socio-economic linkages. The SDG icons are courtesy of the UN SDG communications material. 

Reference - Bandari, Reihaneh, et al. "Participatory Modeling for Analyzing Interactions Between High‐Priority Sustainable Development Goals to Promote Local Sustainability." Earth's Future 11.12 (2023): e2023EF003948.

A simple model of the earths climate to show how greenhouse gases and aerosols in the atmosphere affect the temperature of the earths surface and the atmosphere​.

HANDY Model of Societal Collapse from Ecological Economics Paper 

Simple Health Care Supply and Demand Interactions

This model simulates the growth of carp in an aquaculture pond, both with respect to production and environmental effects.

 Carp are mainly cultivated in Asia and Europe, and contribute to the world food supply.

Aquaculture currently produces sixty million tonnes of fish and shellfish every year. In 2011, aquaculture production overtook wild fisheries for human consumption.

This paradigm shift last occurred in the Neolithic period, ten thousand years ago, when agriculture displaced hunter-gatherers as a source of human food.

Aquaculture is here to stay, and wild fish capture (fishing) will never again exceed cultivation.

Recreational fishing will remain a human activity, just as hunting still is, after ten thousand years - but it won't be a major source of food from the seas.

The best way to preserve wild fish is not to fish them.

Small community that becomes overpopulated requires change in order to survive

HANDY Model of Societal Collapse from Ecological Economics Paper 

This simple model will attempt to demonstrate how modern civilization's groundwater practices are unsustainable and how they are affected by the changing climate.

Japan is facing a decline in forestry engaged population. By using this model you can speculate the optimum allocation of the workforce.

This model incorporates several options in examining fisheries dynamics and fisheries employment. The two most important aspects are the choice between I)managing based on setting fixed quota versus setting fixed effort , and ii) using the 'scientific advice' for quota setting  versus allowing 'political influence' on quota setting (the assumption here is that you have good estimates of recruitment and stock assessments that form the basis of 'scientific advice' and then 'political influnce' that desires increased quota beyond the scientific advice).

HANDY Model of Societal Collapse from Ecological Economics Paper 

Simple Health Care Supply and Demand Interactions

This model incorporates several options in examining fisheries dynamics and fisheries employment. The two most important aspects are the choice between I)managing based on setting fixed quota versus setting fixed effort , and ii) using the 'scientific advice' for quota setting  versus allowing 'political influence' on quota setting (the assumption here is that you have good estimates of recruitment and stock assessments that form the basis of 'scientific advice' and then 'political influnce' that desires increased quota beyond the scientific advice).

There is a general belief that wind and solar will enable us to get fossil-fuels-use to net-zero. This is, unfortunately, impossible as an examination of only some limitations and constraints associated with solar and wind energy will show. Solar panels and wind turbines have now been used for many years, but until now they represent only a tiny fraction of total energy use (not just electricity but all forms of energy).  In 2020, wind accounted for 3% of the world’s total energy consumption and solar amounted to 1% of total energy. Thus, the combination of wind and solar produced only 4% of world energy in 2020. How long will we have to wait before they can generate enough energy to power the world? The climate emergency will not wait.  Solar panels and wind turbines have average lifespans of around 15 to 30 years, then they need to be replaced. However, the manufacture of the replacements will require fossil fuels since one cannot use wind or solar to build wind and solar. Further, solar panels do not supply enough energy. The net-energy gained from solar panels is only about 3.9:1. This net-energy ratio is known as ‘energy return on energy invested’ (EROI) and is critically important.  Unfortunately, the EROI of solar is far too low to power a modern industrial society, which requires an EROI of about 12:1. There is also the question of space. Renewable energy sources can take up 1000 times more space than fossil fuel – that is bad news for agriculture and food production in a world that is already experiencing food shortages because of global warming. If you take these limitations into consideration, then it becomes clear that solar and wind cannot solve our energy problem – they are a fix that will inevitably fail. 

Template for mapping SDG linkages for sustainable systems engineering

Challenges in sustainability are multilevel.
This diagram attempts to summarize levels of self reinforcing destructive dynamics, authors that deal with them, and point of leverage for change.

The base of the crisis is a mechanistic rather than ecological worldview. This mechanistic worldview is based on outdated science that assumed the universe to be a large machine. In a machine there is an inside and an outside. The health of the inside is important for the machine, the outside not. In an ecological view everything is interconnected, there is no clear separation in the future of self and other. All parts influence the health of other parts. To retain health sensitivity and democracy are inherent. The sense of separation from other that keeps the mechanistic worldview dominant is duality. Being cut off from spiritual traditions due to a mechanistic view of science people need access to inter-spirituality to reconnect with the human traditions and tools around connectedness, inner discovery, and compassion. Many books on modern physics and biology deal with the system view implications. "The coming interspiritual age" deals with the need to connect spiritual traditions and science.

At the bottom for the dynamic is an individual a sense of disconnectedness leads to a dependency on spending and having rather than connecting. The connecting has become too painful and dealing with it unpopular in our culture. Joanna Macy deals with this in Active Hope. 

This affluenza and disconnection is worsened by a market that floods one with advertisements aimed at creating needs and a sense of dissatisfaction with that one has.

National economies are structured around maximising GDP which means maximising consumption and financial capital movement. This is at the cost of local economies. These same local economies are needed for balanced happiness as well as for sustainability.

Generally institutions focus on maximising consumption rather than sustaining life support systems. David Korten covers this well.

Power and wealth is confused in this worldview. In striving for wealth only power is striven for in the form of money and monopoly.

Those at the head of large banks and corporations tend to be there because they exemplify this approach. They have few scruples about enforcing this approach onto everyone through wars and disaster capitalism. Naomi Klein and David Estulin documented this.

Power has become so centralized that we need this understanding to be widespread and include many of those in power. Progress of all of these levels are needed to show them and all that another way is possible.

This simple model will attempt to demonstrate how modern civilization's groundwater practices are unsustainable and how they are affected by the changing climate.

HANDY Model of Societal Collapse from Ecological Economics Paper 

WIP Cloned from WIP Africa Just Transition insight including (Fig 3.1 from Jorgen Randers book 2052 a Global Forecast for the Next Forty Years) with Fadhel Kaboub MMT Perspective to continue top down work on my slides of clds and macroeconomics