Sustainability Models

These models and simulations have been tagged “Sustainability”.

Related tagsEnvironment

HANDY Model of Societal Collapse from Ecological Economics  Paper   see also D Cunha's model at  IM-15085
HANDY Model of Societal Collapse from Ecological Economics Paper 
see also D Cunha's model at IM-15085
 That efficiency gains achieved by employing technological
solutions often have a negative effect has been known since 1856 when William
Stanley Jevons described this counterintuitive situation, which has become
known as  ‘Jevons Paradox’ . This simple graph illustrates this effect. Be it extraction

That efficiency gains achieved by employing technological solutions often have a negative effect has been known since 1856 when William Stanley Jevons described this counterintuitive situation, which has become known as ‘Jevons Paradox’. This simple graph illustrates this effect. Be it extraction of a mineral or the production of a product, employing technology will make the process more efficient, initially, and lower the price of the product produced. However, the lower prices will increase demand and, therefore, the use of the resources employed. Unless more or better technology is employed, the extra demand is likely to lead to a price increase cancelling the initial beneficial effect, and in addition, the resource may be pushed to exhaustion. The technological fix will have failed. Note, ‘solar’ and ‘wind’ are also subject to a ‘Fixes-that-Fails’ structure, but this requires a separate illustration. 

This simple model will attempt to demonstrate how modern civilization's groundwater practices are unsustainable and how they are affected by the changing climate.
This simple model will attempt to demonstrate how modern civilization's groundwater practices are unsustainable and how they are affected by the changing climate.
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 bas
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 This mechanistic worldview is based on outdated science that assumed the universe to be a large machine.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.
  The World Socio-Economics model is computer model to simulate the consequence of interactions between the earth and human systems based on the World3 model by the work of Club of Rome, The Limits to Growth[1].     The World3 model builds by system dynamics theory that is has an approach to underst
The World Socio-Economics model is computer model to simulate the consequence of interactions between the earth and human systems based on the World3 model by the work of Club of Rome, The Limits to Growth[1].

The World3 model builds by system dynamics theory that is has an approach to understanding the nonlinear behaviour of complex systems over time using stocks, flows, feedback loops, table functions and time delays.

The Limits to Growth concludes that, without substantial changes in resource consumption, "the most probable result will be a rather sudden and uncontrollable decline in both population and industrial capacity". 

Since the World3 model was originally created, it has had minor tweaks to get to the World3-91 model used in the book Beyond the Limits[2], later improved to get the World3-03 model used in the book Limits to Growth: the 30 year update[3].

References;
[1] Meadows, Donella H., Meadows, Dennis L., Randers, Jørgen., Behrens III, William W (1972). The Limits to Growth. 

[2] Meadows, Donella H., Dennis L. Meadows, Randers, Jørgen., (1992). Beyond the limits: global collapse or a sustainable future.

[3] Meadows, Dennis., Randers, Jørgen., (2004). The limits to growth: the 30-year update.
4 2 months ago
WIP R. Willamo et al. / Ecological Modelling 370 (2018) 1–13  article  Learning how to understand complexity and deal with sustainability challenges – A framework for a comprehensive approach and its application in university education
WIP R. Willamo et al. / Ecological Modelling 370 (2018) 1–13 article Learning how to understand complexity and deal with sustainability challenges – A framework for a comprehensive approach and its application in university education
This model simulates the growth of carp in an aquaculture pond, both with respect to production and environmental effects.  Both the anabolism and fasting catabolism functions contain elements of allometry, through the m and n exponents that reduce the ration per unit body weight as the animal grows
This model simulates the growth of carp in an aquaculture pond, both with respect to production and environmental effects.

Both the anabolism and fasting catabolism functions contain elements of allometry, through the m and n exponents that reduce the ration per unit body weight as the animal grows bigger.

The 'S' term provides a growth adjustment with respect to the number of fish, so implicitly adds competition (for food, oxygen, space, etc).

 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 May 2013, 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.
    Primitive
Legend:  

  Grocery Store Inventory  is a stock that
represents the amount of perishable food units available for sale to consumers.
This stock is directly affected by the forces of economics as grocers can only
sell at the level that their produce is demanded. As a result, once this

Primitive Legend:

Grocery Store Inventory is a stock that represents the amount of perishable food units available for sale to consumers. This stock is directly affected by the forces of economics as grocers can only sell at the level that their produce is demanded. As a result, once this stock exceeds demand, it will rise as food no longer sold.

Overstock Waste is a stock that is designed to model the overstock display assumption which states that consumers have more incentive to purchase foods from fully stocked piles rather than empty ones. This stock exists and accumulates over time because grocers purchase excess produce to give buyers incentive.

Ugly Food Stock is the stock that represent the amount of perfectly nutritious ugly produce neglected by consumers as they only buy the prettiest clusters from the display. This stock includes foods such as brown bananas, dented apples, and so forth. These ugly foods are left behind in addition to the overstock waste.

Education Programs is the stock that contains the amount of ugly foods delivered to local school districts for educating students on the significance of ugly food discrimination. These foods are utilized in various forms of comparative demonstrations to illustrate to students that ugly foods are just as nutritious as prettier alternatives.

Compost Alternatives is the stock that depicts the efforts of grocery stores trying to implement a method that allows them to reduce the amount of waste they send to the landfill. These compost methods may be in the form on enriched manure given back to the farmers that supply the produce.

10 Food Units/Resale Output is the variable that illustrates the amount of food units required to make a product for resale. For example, it takes 10 units of melons to make an assorted melon platter. Likewise, a single smoothie for resale will require 5 units of assorted fruits.

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 'poli
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

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

Rough draft of model to relate Edwards Aquifer water storage to spring flow, pumping rates and other variables.
Rough draft of model to relate Edwards Aquifer water storage to spring flow, pumping rates and other variables.
Assume 10 units of food make up one platter for resale.
Assume 10 units of food make up one platter for resale.
 The fishing sector
(artisanal and industrial) considered as a renewable resource is a sector with
a strong potential to create employment and new resources necessary for the population. It is also an important source of foreign
exchange due to the export of sea products and represent a potential fo

The fishing sector (artisanal and industrial) considered as a renewable resource is a sector with a strong potential to create employment and new resources necessary for the population. It is also an important source of foreign exchange due to the export of sea products and represent a potential for the development of entrepreneurship.

Indeed, Benin, a West African country with a population of about twelve million inhabitants, has a 125 km long coastline. Benin's fisheries sector contributes only 3% of the GDP, forms a very small part of exports, while Beninese fisheries products are in increasing demand in Europe.

However, the widespread use of non-regulatory fishing methods and gear, the uncontrolled increase in fishing effort, the degradation of ecosystems, and the pollution of water bodies by household and industrial waste mean that national production of fishery is stagnating at an average of 39,500 tons per year.

The increase in commercial fisheries production is therefore becoming an imperative in order to continue to guarantee the fishing industry and to safeguard its sustainability and to increase its contributions to the GDP. Simulation models can be used to help making durable decisions.

In the proposed model, we assumed that the largest population of fishermen harvesting the most important species of fish in the large sea of Benin, the shrimp.

The complete the fishery system consists of the coupled dynamic systems of the Fish population and the one hand and the Fishing boat (fishing industry) on the other, that have been represented by the Stocks.

Earnings of the fishermen are used to maintain, buy new fishing boats or to replace old boats that go out of commission, but also, to take care of families.


The declining koala population in South East Queensland is being caused by a number of factors. These are, climate change, urbanisation and disease. Through government intervention and preventative measures the koala population may stand a chance from the growing development in South East Queensland
The declining koala population in South East Queensland is being caused by a number of factors. These are, climate change, urbanisation and disease. Through government intervention and preventative measures the koala population may stand a chance from the growing development in South East Queensland.