Geography and environment

The following parameters determine characteristics of the geography and environment of the simulation. For example, how to use the temperature or rainfall data in the climate files and the size of the nodes in the simulation.

Note

Parameters are case-sensitive. For Boolean parameters, set to 1 for true or 0 for false. Minimum, maximum, or default values of “NA” indicate that those values are not applicable for that parameter.

EMOD does not use true defaults; that is, if the dependency relationships indicate that a parameter is required, you must supply a value for it. However, many of the tools used to work with EMOD will use the default values provided below.

JSON format does not permit comments, but you can add “dummy” parameters to add contextual information to your files. Any keys that are not EMOD parameter names will be ignored by the model.

Parameter

Data type

Minimum

Maximum

Default

Description

Example

Air_Temperature_Filename

string

NA

NA

_add-your-air-temperature-file_.bin

The path to the input file that defines air temperature data measured two meters above ground. Climate_Model must be set to CLIMATE_BY_DATA. The file must be in .bin format.

{
    "Climate_Model": "CLIMATE_BY_DATA",
    "Air_Temperature_Filename": "Namawala_single_node_air_temperature_daily.bin"
}

Air_Temperature_Offset

float

-20

20

0

The linear shift of air temperature in degrees Celsius. Climate_Model must be set to CLIMATE_BY_DATA.

{
    "Air_Temperature_Offset": 1
}

Air_Temperature_Variance

float

0

-16

2

The standard deviation (in degrees Celsius) for normally distributed noise applied to the daily air temperature values when Climate_Model is configured as CLIMATE_CONSTANT or CLIMATE_BY_DATA. Enable_Climate_Stochasticity must be set to true (1).

{
    "Enable_Climate_Stochasticity": 1,
    "Air_Temperature_Variance": 2
}

Base_Air_Temperature

float

-55

45

22

The air temperature, in degrees Celsius, where Climate_Model is set to CLIMATE_CONSTANT.

{
    "Climate_Model": "CLIMATE_CONSTANT",
    "Base_Air_Temperature": 30
}

Base_Land_Temperature

float

-55

60

26

The land temperature, in degrees Celsius, where Climate_Model is set to CLIMATE_CONSTANT.

{
    "Climate_Model": "CLIMATE_CONSTANT",
    "Base_Land_Temperature": 20
}

Climate_Model

enum

NA

NA

CLIMATE_OFF

How and from what files the climate of a simulation is configured. The possible values are:

CLIMATE_OFF

No climate files used.

CLIMATE_CONSTANT

Uses the conditional parameters that give the fixed values of temperature or rain for land temperature, air temperature, rainfall, and humidity.

CLIMATE_KOPPEN

Uses an input file that decodes Koppen codes by geographic location.

CLIMATE_BY_DATA

Reads everything out of several input files with additional parameters that allow the addition of stochasticity or scale offsets.

{
    "Climate_Model": "CLIMATE_CONSTANT"
}

Climate_Update_Resolution

enum

NA

NA

CLIMATE_UPDATE_YEAR

The resolution of data in climate files. Climate_Model must be set to CLIMATE_CONSTANT, CLIMATE_BY_DATA, or CLIMATE_KOPPEN. Possible values are:

CLIMATE_UPDATE_YEAR CLIMATE_UPDATE_MONTH CLIMATE_UPDATE_WEEK CLIMATE_UPDATE_DAY CLIMATE_UPDATE_HOUR

{
    "Climate_Update_Resolution": "CLIMATE_UPDATE_DAY"
}

Default_Geography_Initial_Node_Population

integer

0

1000000

1000

When using the built-in demographics for default geography, the initial number of individuals in each node. Note that the built-in demographics feature does not represent a real geographical location and is mostly used for testing. Enable_Demographics_Builtin must be set to true (1).

{
    "Enable_Demographics_Builtin": 1,
    "Default_Geography_Initial_Node_Population": 1000,
    "Default_Geography_Torus_Size": 3
}

Default_Geography_Torus_Size

integer

3

100

10

When using the built-in demographics for default geography, the square root of the number of nodes in the simulation. The simulation uses an N x N square grid of nodes with N specified by this parameter. If migration is enabled, the N x N nodes are assumed to be a torus and individuals can migrate from any node to all four adjacent nodes.

To enable migration, set Migration_Model to FIXED_RATE_MIGRATION. Built-in migration is a form of “local” migration where individuals only migrate to the adjacent nodes. You can use the x_Local_Migration parameter to control the rate of migration. The other migration parameters are ignored. Note that the built-in demographics feature does not represent a real geographical location and is mostly used for testing.

Enable_Demographics_Builtin must be set to true (1).

{
    "Enable_Demographics_Builtin": 1,
    "Default_Geography_Initial_Node_Population": 1000,
    "Default_Geography_Torus_Size": 3
}

Enable_Climate_Stochasticity

boolean

0

1

0

Controls whether or not the climate has stochasticity. Climate_Model must be set to CLIMATE_CONSTANT or CLIMATE_BY_DATA. Set the variance using the parameters Air_Temperature_Variance, Land_Temperature_Variance, Enable_Rainfall_Stochasticity, and Relative_Humidity_Variance.

{
    "Climate_Model": "CLIMATE_BY_DATA",
    "Enable_Climate_Stochasticity": 1,
    "Air_Temperature_Variance": 2,
    "Enable_Rainfall_Stochasticity": 1,
    "Land_Temperature_Variance": 2,
    "Relative_Humidity_Variance": 0.05
}

Enable_Rainfall_Stochasticity

boolean

0

1

1

Controls whether or not there is stochastic variation in rainfall; set to true (1) for stochastic variation of rainfall that is drawn from an exponential distribution (with a mean value as the daily rainfall from the Climate_Model values CLIMATE_CONSTANT or CLIMATE_BY_DATA), or set to false (0) to disable rainfall stochasticity.

{
    "Enable_Climate_Stochasticity": 1,
    "Air_Temperature_Variance": 2,
    "Enable_Rainfall_Stochasticity": 1,
    "Land_Temperature_Variance": 2,
    "Relative_Humidity_Variance": 0.05
}

Koppen_Filename

string

NA

NA

_add-your-koppen-climate-file_.json

The path to the input file used to specify Koppen climate classifications. Climate_Model must be set to CLIMATE_KOPPEN.

{
    "Koppen_Filename": "Mad_2_5arcminute_koppen.dat"
}

Land_Temperature_Filename

string

NA

NA

_add-your-land-temp-file_.bin

The path of the input file defining temperature data measured at land surface; used only when Climate_Model is set to CLIMATE_BY_DATA. The file must be in .bin format.

{
    "Land_Temperature_Filename": "Namawala_single_node_land_temperature_daily.bin"
}

Land_Temperature_Offset

float

-20

20

0

The linear shift of land surface temperature in degrees Celsius; only used when Climate_Model is set to CLIMATE_BY_DATA.

{
    "Land_Temperature_Offset": 0
}

Land_Temperature_Variance

float

0

7

2

The standard deviation (in degrees Celsius) for normally distributed noise applied to the daily land temperature values when Climate_Model is configured to CLIMATE_CONSTANT or CLIMATE_BY_DATA; only used if the Enable_Climate_Stochasticity is set to true (1).

{
    "Land_Temperature_Variance": 1.5
}

Node_Grid_Size

float

0.00416

90

0.004167

The spatial resolution indicating the node grid size for a simulation in degrees.

{
    "Node_Grid_Size": 0.042
}

Rainfall_Filename

string

NA

NA

_add-your-rainfall-file_.bin

The path of the input file which defines rainfall data. Climate_Model must be set to CLIMATE_BY_DATA. The file must be in .bin format.

{
    "Rainfall_Filename": "Namawala_single_node_rainfall_daily.bin"
}

Rainfall_Scale_Factor

float

0.1

10

1

The scale factor used in multiplying rainfall value(s). Climate_Model must be set to CLIMATE_BY_DATA.

{
    "Rainfall_Scale_Factor": 1
}

Relative_Humidity_Filename

string

NA

NA

_add-your-relative-humidity-file__hum.bin

The path of the input file which defines relative humidity data measured 2 meters above ground. Climate_Model must be set to CLIMATE_BY_DATA. The file must be in .bin format.

{
    "Relative_Humidity_Filename": "Namawala_single_node_relative_humidity_daily.bin"
}

Relative_Humidity_Scale_Factor

float

0.1

10

1

The scale factor used in multiplying relative humidity values. Climate_Model must be set to CLIMATE_BY_DATA.

{
    "Relative_Humidity_Scale_Factor": 1
}

Relative_Humidity_Variance

float

0

0.12

0.05

The standard deviation (in percentage) for normally distributed noise applied to the daily relative humidity values when Climate_Model is configured as CLIMATE_CONSTANT or CLIMATE_BY_DATA. Enable_Climate_Stochasticity must be set to true (1).

{
    "Relative_Humidity_Variance": 0.05
}