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[screen shot]

If clicking does not initiate a download, try right clicking or control clicking and choosing "Save" or "Download".(The run link is disabled for this model because it was made in a version prior to NetLogo 6.0, which NetLogo Web requires.)


This model is inspired by Tom Seeley's work on the decision-making system of honeybees. It explores the impact of decision-making systems and science and anti-science dissemination on climate change.


Humans have founded a colony on a new planet. Earth has overheated. The cause is disputed, but now they have a chance to start afresh. On this planet the oxygen produced by forests and the carbon dioxide produced by factories diffuse slowly through the atmosphere producing pockets of the gases. There are three kinds of human agents - climate scientists, anti-scientists and citizens. Climate scientists collect temperature data. The user can choose between two decision-making systems. In the case of climate scientist quorum, the system is modelled after honeybees. When a quorum of scientists agree that climate change is happening, policy makers agree to either plant more forests and demolish factories or the other way around depending on the direction of temperature change. In the case of public majority, there has to be a majority consensus before action is taken.


Click the SETUP button to set up the world. Click the GO button to start the simulation. Choose the decision-making system. The action-interval sets the interval before the next action can take place. The smaller this number the more vigorous is the response to climate change. The quorum-threshold sets the number of scientists that must agree that climate change is taking place (in whichever direction) before action is taken. The temperature-threshold, in degrees, sets how much of temperature difference must take place before climate change is perceived by the climate scientists. The scientist-collection-interval sets the interval between which temperature data collection takes place. These two variables effectively determine how good a job the climate scientists are doing. Note that if climate-scientist quorum is chosen as the decision-making system then the public majority variables do not apply.

The majority-threshold sets the proportion of citizens that must agree that climate change is taking place before action is taken. Mean public wisdom sets the mean of a normal distribution for wisdom for citizens. Individuals with a wisdom value of 0.67 or more always defer to climate scientists. Individuals with wisdom value of -0.67 or less always defer to anti-scientists (the outcome is obvious, but is left in for completeness). Individuals with an in-beween value are equally persuaded by scientists and anti-scientists. Science-dissemination sets how mobile scientists are and hence, in effect, how well they are popularising the state of the climate. Anti-scientists take the contrary position to scientists. When anti-science dissemination is set high anti-scientists are effective in popularising their contrary position. If public wisdom is set high then the anti-science dissemination value does not apply. The default value for dissemination is set higher for anti-science than science to reflect the situation in the real world. In the context of global warming, Lord Christopher Monckton has one hundred times the presence on YouTube as John Houghton in the context of global warming. Monckton has been deacribed world’s leading global warming sceptic. However, his credentials are in journalism and classics and he has not even published one peer-reviewed scientific paper, let alone in climate science. Houghton is professor of atmospheric physics at Oxford University and co-chair of the Intergovernmental Panel on Climate Change's (IPCC) scientific assessment working group. The IPCC is a body of thousands of scientists comprehensively assessing the risk of climate change.

Scientist and citizen-perceivers plots the percentage of scientists and citizen that accept that global warming is taking place respectively. Initial-T is the initial and ideal temperature. Mean-T is the mean actual temperature of patches.


Much needs to be in place in order to deal effectively with climate change, otherwise climate could oscillate wildly. Whatever the decision-making system, the data gathering has to be good and action-interval needs to be appropriate. If the public majority system is chosen, then a lot more needs to be in place. Even if public wisdom is high, science dissemination needs to be high. If public wisdom is intermediate, then science dissemination needs to be much higher still, especially if there are anti-scientists around and especially if anti-science dissemination is high.


There is no tipping point in this model. One way to implement this would be to have forests die off if the temperature is too high.


The diffuse primitive is used to diffuse oxygen and carbon dioxide. The random-normal function is used to create a public with a normal distribution of wisdom.


Seeley, T. D. (2010) Honeybee Democracy. Princeton University Press, Princeton.

Seeley, T. (2010) The Five Habits of Highly Effective Honeybees. Princeton University Press, Princeton

## Author information

Mike L Anderson


Copyright 2012 Mike L Anderson
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