Standard parameters

In OpenSCM a ‘parameter’ is any named input or output variable of a model, e.g. CO₂ emissions, equilibrium climate sensitivity, aerosol forcing scaling. As described here, parameters are given in a hierarchy, e.g. Emissions -> CO2 -> Industrial.

Simple climate models come in many different shapes and forms hence we do not expect them to all be able to do everything. However, to be included in OpenSCM they should make sure their parameters fit into these standard parameters as far as possible to ensure models can be interchanged easily. Of course, model-specific parameters are also able to be used (see also Writing a model adapter).

Conventions

In the following, ‘pre-industrial’ refers to an unperturbed state of the climate. Individual adapters can translate this into whatever year they need to for their model, but they should do such translations with this definition in mind.

‘Reference period’ refers to the period a given variable is reported relative to the mean of. For example, ‘surface temperature relative to a 1961-1990 reference period’ refers to surface temperatures relative to the mean of the period 1961-1990. We are not yet sure how best to handle these reference periods in variables, if you have ideas please contribute to the discussions in #167.

Aggregation

Parameters in OpenSCM come as part of a hierarchy, in the following separated by the | character. For example, Emissions|CO2|Energy. Emissions|CO2|Energy is emissions of CO₂ from the energy sub-sector (whatever ‘energy’ happens to mean in this context). As far as it makes sense, parameters that are higher in the hierarchy (e.g. Emissions|CO2 is ‘higher’ than Emissions|CO2|Energy) are the sum of all the variables which are one level below them in the hierarchy. For example, if Emissions|CO2|Energy, Emissions|CO2|Transport and Emissions|CO2|Agriculture are provided, Emissions|CO2 would be the sum of these.

Standards

Standard parameters

Below we provide a list of the OpenSCM standard parameters adapters must adhere to as far as a specific variable concerns them. Alongside we give the type of unit that the parameter should be given in and how it should be expected by adapters. Conversion between particular units is done automatically if possible.

In the following, <GAS> can be one of the standard Gases.

Standard parameters

Parameter name 0	Parameter name 1	Parameter name 2	Unit type	Note
Start Time			np.datetime64 object	Time of the first time step of the model run
Stop Time			np.datetime64 object	Time of the last time step of the model run
Emissions	<GAS>		mass <GAS> / time
Atmospheric Concentrations	<GAS>		parts per X where X is million, billion, trillion etc.	Aggregation possible, but does not always make sense
Pool	<GAS>		mass <GAS>
Radiative Forcing			power / area	Aggregation gives total forcing, but be carful of double reporting, e.g. providing Radiative Forcing|Aerosols|Direct Effect and Radiative Forcing|Aerosols|NOx
Radiative Forcing	<GAS>
Radiative Forcing	Aerosols
Radiative Forcing	Aerosols	Direct Effect
Radiative Forcing	Aerosols	Indirect Effect
Radiative Forcing	Aerosols	SOx
Radiative Forcing	Aerosols	NOx
Radiative Forcing	Aerosols	OC
Radiative Forcing	Aerosols	BC
Radiative Forcing	Land-use Change
Radiative Forcing	Black Carbon on Snow
Radiative Forcing	Volcanic
Radiative Forcing	Solar
Radiative Forcing	External
<X> to <Y> Flux			mass / time	See Material Fluxes
Surface Temperature			temperature	Surface air temperature i.e. tas
Ocean Temperature			temperature	Surface ocean temperature i.e. tos
Ocean Heat Content			energy
Sea Level Rise			length
Equilibrium Climate Sensitivity			temperature
Transient Climate Response			temperature
Radiative Forcing 2xCO2			power / area	Radiative forcing due to a doubling of atmospheric CO2 concentrations from pre-industrial level

Gases

Gases

Name	Description
CO2	Carbon
CH4	Methane
N2O	Nitrous oxide
SOx	Sulfur oxide
CO	Carbon monoxide
NMVOC	Volatile organic compound
NOx	Nitrogen oxide
BC	Black carbon
OC	Organic carbon
NH3	NH3
NF3	NF3
CF4	CF4
C2F6	C2F6
C3F8	C3F8
cC4F8	cC4F8
C4F10	C4F10
C5F12	C5F12
C6F14	C6F14
C7F16	C7F16
C8F18	C8F18
CCl4	CCl4
CHCl3	CHCl3
CH2Cl2	CH2Cl2
CH3CCl3	CH3CCl3
CH3Cl	CH3Cl
CH3Br	CH3Br
HFC23	HFC23
HFC32	HFC32
HFC4310	HFC4310
HFC125	HFC125
HFC134a	HFC134a
HFC143a	HFC143a
HFC152a	HFC152a
HFC227ea	HFC227ea
HFC236fa	HFC236fa
HFC245fa	HFC245fa
HFC365mfc	HFC365mfc
CFC11	CFC11
CFC12	CFC12
CFC113	CFC113
CFC114	CFC114
CFC115	CFC115
HCFC22	HCFC22
HCFC141b	HCFC141b
HCFC142b	HCFC142b
SF6	SF6
SO2F2	SO2F2
Halon1202	Halon1202
Halon1211	Halon1211
Halon1301	Halon1301
Halon2402	Halon2402

Material Fluxes

These variables can be used to store the flux of material within the model. They should be of the form <X> to <Y> Flux where the material is flowing from <X> into <Y> (and hence negative values represent flows from <Y> into <X>):

• Land to Air Flux|CO2|Permafrost (mass carbon / time) - land to air flux of CO₂ from permafrost

• Land to Air Flux|CH4|Permafrost (mass methane / time)

Standard regions

Similarly to variables, regions are also given in a hierarchy. Regions which are higher in the hierarchy are the sum of all the regions which are one level below them in the hierarchy (be careful of this when looking at e.g. CO₂ concentration data at a regional level).

The hemispheric regions should be fairly obvious and well-defined. The land/ocean split is somewhat fuzzily defined as the transition between land and ocean does not have a precise definition. We don’t provide a clear definition because a) there isn’t an agreed one in the literature and b) no simple climate model is detailed enough for the slight fuzziness around these definitions to matter. We choose to put the hemispheres before the ocean/land split in the hierarchy because it makes more sense to us but are happy to discuss further if desired (raise an issue).

Descriptions of the rest of the regions can be found in the ‘Description’ column below.

Warning Be careful, if you mix multiple regional conventions (e.g. reporting both ("World", "Land") and ("World", "R5ASIA")), then your ("World") total will double count some quantities and so may provide misleading information. There is no way for OpenSCM to reasonably keep track of what overlaps with what so we can’t automate this process (if you think you have an idea of how to do this, please make a PR :D).

Gases

Name 0	Name 1	Name 2	Description
World			Entire globe
World	Northern Hemisphere		Northern hemisphere
World	Northern Hemisphere	Ocean	Northern hemisphere ocean
World	Northern Hemisphere	Land	Northern hemisphere land
World	Southern Hemisphere		Southern hemisphere
World	Southern Hemisphere	Ocean	Southern hemisphere ocean
World	Southern Hemisphere	Land	Southern hemisphere land
World	Ocean		Ocean
World	Land		Land
World	R5ASIA		Non-OECD Asia - see IIASA AR5 database
World	R5REF		Reforming economies of Eastern Europe and the Former Soviet Union (also known as R5EIT i.e. economies in transition) - see IIASA AR5 database
World	R5MAF		Middle East and Africa - see IIASA AR5 database
World	R5OECD		OECD - see IIASA AR5 database
World	R5LAM		Latin America and the Caribbean - see IIASA AR5 database
World	R5.2ASIA		Most Asian countries - see IIASA SSP database
World	R5.2REF		Reforming economies of Eastern Europe and the Former Soviet Union - see IIASA SSP database
World	R5.2MAF		Middle East and Africa - see IIASA SSP database
World	R5.2OECD		OECD - see IIASA SSP database
World	R5.2LAM		Latin America and the Caribbean - see IIASA SSP database
World	Bunkers		Typically used to capture all non-country associated emissions i.e. international shipping (and sometimes aviation) - be careful with definition