Compset Naming: first letter

Background

The configuration of an E3SM case is specified by a long string called a “component set”. Here is an example for an atmosphere-only case:

1850_CAM5%CMIP6_CLM45%SPBC_CICE%PRES_DOCN%DOM_SROF_SGLC_SWAV

That’s a lot to type so every compset has a shorter alias and the first letter in that alias indicates what combination of components are full active models or not. The alias for the above is:

F1850C5-CMIP6

The meaning of the first letter in the component set alias is inherited from CESM and has a long history. The below table is modified from http://www.cesm.ucar.edu/models/cesm1.0/cesm/cesm_doc_1_0_4/x42.html but these conventions date back to when the model was called CCSM.

In the table below, you’ll see components like “datm” and “swav”. To turn off feedbacks, active components can be substituted by a version that just sends data e.g. “datm” is a data atmosphere model. A “data” model sends real values for all expected fields (from files) to the coupler so that the rest of the system can’t tell if its a full model or not.

In some cases you don’t even need a data model. You just need something for the coupler to call in the place it expects. A “stub” model serves this purpose. e.g. “swav” is a stub wave model. No data is sent.

Also in the table below, “glc” is the land-ice model (because it used to be called the “glacier” model).

To distinguish between CESM and E3SM cases, we adopted different naming for some compset aliases including using multiple letters.

Original letters

Designation

Components

Details

Designation

Components

Details

A

datm,dlnd,dice,docn,drof,sglc, swav

All DATA components with stub glc and wav (used primarily for testing the coupler)

B

NOT USED by E3SM.

The “fully coupled” cases in CESM.

C

NOT USED by E3SM.

in CESM, POP active with data atm, lnd(runoff), and ice plus stub glc.

D

NOT USED by E3SM

This would be an active MPAS-sea ice only case with data atm and ocn and stub lnd, runoff, glc, wav.

E

eam, elm,mpas-seaice, docn,sglc, swav

EAM, ELM, MOSART and CICE active with data ocean (som mode) plus stub glc, wav. We have these defined but don’t use/test them. Like an F-case but the sea-ice is fully active and active runoff is added.

F

eam, elm, cice, docn, srof, sglc, swav

(need to replace cice with mpas-seaice equivalent)

EAM, ELM, and old CICE (prescribed mode) active with data ocean (sstdata mode) plus stub rof, wav and glc. What we use when we say “atmosphere only”

G

Called “GMPAS”. datm, slnd, mpas-ocean, mpas-seaice, drof, swav, sglc

Active sea ice and ocean,

H

NOT USED by E3SM

This would be the same as a G case but stub runoff instead of data runoff. We have none of these defined.

I

datm, elm, mosart, sice,socn, swav, sglc

ELM and MOSART active with data atm and stub ice, ocean, wave and glc. NOTE Some I-cases have stub atm.

IG

datm, elm, mosart, sice, socen, save, mali, swav

land-ice with active land and river. datm, stub otherwise.

S

satm,slnd,sice,socn,srof,sglc,swav

All STUB components (used for testing only)

TG

satm, elm, sice,socn,srof, mpas-landice, swav

Active land model and land-ice with stub everything else

V

satm, slnd, sice, socn, srof, sglc, ww3

Active wave model only case

X

xatm,xlnd,xice,xocn,sglc,swav

All DEAD components except for stub glc and wav (used for testing only)

E3SM additions

Designation

Components

Details

Designation

Components

Details

WCYCLE (fka A_WCYCLE)

eam,elm,mpas-ocean,mpas-seaice, mosart, sglc

FULLY Active water cycle cases with stub glc, wav. Our version of a “B-case”. The “A_” was for ACME so we will drop that in v2.

BGC

eam,elm,mpas-ocean,mpas-seaice, mosart, sglc with BGC pieces turned on.

FULLY active BGC cases with stub glc, wav

CMPASO

datm,dice,dlnd, mpas-ocean, drof, sglc, swav

mpas-ocean active with data atm, land, runoff and seaice. stub glc and wav.

CRYO

eam,elm,mpas-ocean,mpas-seaice, mosart, mpas-landice, stub wav.

FULLY active with stub wav.

DTESTM

datm,slnd, mpas-seaice, docn, drof, sglc, swav

MPAS-seaice with data atm, ocn, and runoff. Stub glc, wav.

GMPAS

datm,slnd, mpas-seaice, mpas-ocean, drof, sglc, swav

MPAS-ocean and MPAS-seaice active with data atm and runoff, stub lnd, glc, wav. The ocean and sea-ice version of an F-case.

MALI

mpas-landice, satm, slnd, socn, srof, swav

MPAS-landice and stub everything else.

MPAS-LISO

active mpas-landice, seaice and ocean. datmk slnd, swav

All MPAS models active