Getting Started

Eruption! is a web-based simulation of volcanic activity leading up to a volcanic crisis, a situation in which lives are endangered. The simulation covers twenty-five days of volcanic activity, but time is accelerated so that the entire exercise takes about twelve minutes to complete.

Your task, as a volcanologist, is to collect data and interpret data indicating the level of volcanic activity and determine the volcano crisis code:  


Code Red

Extreme danger of eruption.
Results in the immediate and total evacuation of the surrounding population.

Code Orange

High activity and significant chance of eruption.
Results in the evacuation of non-essential personnel.
(50% of population evacuated).

Code Yellow

Moderate activity and  slight  chance of dangerous eruption.
Results in voluntary evacuations.
(20% of population evacuated)

Code Green

Low activity and little chance of a dangerous eruption.
No evacuations.


Your objective it to save as many lives as possible while keeping costs to a minimum.  Buying and repairing the monitoring equipment costs money, but the biggest cost comes from evacuating people and providing evacuees food and shelter while they are displaced.  Also, the longer people are evacuated, the greater this risk that they will succumb to illness.  You must balance the danger from the volcanic hazard against the dangers and costs of evacuation.

Before you Begin
Before you can evaluate the volcanic hazard, you must first determine how to interpret the instrument readings. Of the tools used to evaluate volcanic activity, among the most commonly used are seismographs, geodimeters, and correlation spectrometers (CoSpecs).  These tools are described in more detail here.  Each of the instruments provides information that only indirectly indicates the likelihood that a volcano will remain dormant. For example, the CoSpec tells us the concentration of sulfur dioxide in the atmosphere.  In order to determine if the volcano is safe, the CoSpec reading must be interpreted.

One way to interpret the instrument readings is to look at historical instruments readings for the same volcano.  If, for a given CoSpec reading, the volcano generally remained safe, then it is likely that similar reading also indicates the volcano is safe.  Past instrument readings and volcanic activity for the volcano you will be analyzing are given here.   

It is helpful to summarize the historical data in a simple table that correlates instrument readings with the likelihood that the volcano remains safe (dormant).  To do this, for each instrument we first divide the instrument readings into three categories – high, medium, and low.  Then within each category we determine the total number of times the instrument reading was within that category.  Next, within each instrument reading category (high, medium, or low), count the total number of times the volcano remains safe (dormant).  For example, suppose that there were 10 times that the CoSpec reading was low (less than 400 tons/day).  And of those 10 times that the reading was low, suppose the volcano remained safe (dormant) 8 times.  Then the probability of the volcano remaining dormant when the CoSpec reading is low is 100 * (8/10) = 80%.

Using this approach, you can calculate the appropriate eruption risk associated with each category of instrument reading  and fill in the following table.

Geodimeter Reading


Chance Volcano Remains Dormant
(Next 12 Hours)



3 - 6


0 - 3


CoSpec Reading


Chance Volcano Remains Dormant
(Next 12 Hours)

> 750


400 - 750


0 - 400


Seismometer Reading


Chance Volcano Remains Dormant
(Next 12 Hours)

> 30


15 - 30


0 - 15


Starting the Simulation

A demo version of the simulation is provided.  No volcanic activity occurs in the demo version, but it will give you a chance to become familiar with how the simulation works.

When the simulation starts you will see a picture of the volcano and the current time of the simulation in the upper right-corner.


Buying Equipment

Your first task it to buy the equipment you will need to monitor the volcano.  To do this, click on the Buy buttons.


Evaluating the Hazard
Use the buttons below the instrument panel to monitor the instrument readings. 


Based on the instrument readings you must decide if it is appropriate to evacuate the nearby residents.  You can choose to evacuate some of the residents (20%), half of the residents, or all of the residents.  


Other Considerations
While evacuated residents will not be affected by the volcano, there are other costs and risks you should consider.  First, there is a cost associated with moving people each time they are either evacuated or returned to their homes.  Second, there is a daily cost associated with supporting (e.g. buying food, water, supplies, etc.) evacuees in the refugee shelters.  These costs and the population status are summarized in the Status section of Eruption!


Finally, the longer the shelter population remains high, the greater likelihood some will die due to disease and other ills associated with high population densities.  The likelihood of an evacuee remaining healthy, i.e., the “health status”, decreases as the average population of the shelter over the simulation increases.  If the population is high for only a short period of time, the health status remains high.  The longer the population remains high, the lower the health status.  In the simulation, the health status is shown graphically.  The health status is based on the average shelter population since the shelter was opened on the first day of the simulation.  This average population is also shown in the simulation.


As with any natural hazard, effective management requires the wise use of limited funds.  While completely evacuating the entire population for the entire period will save all their lives, the cost of doing so is exorbitant.  Can you use the available data to better manage the crisis by using money and resources more effectively?

A project funded by the U.S. National Science Foundation Human and Social Dynamics Program