USE OF ESMF IN THE GEOS-5 MODELING AND ASSIMILATION SYSTEM GEOS-5 ESMF Design Overview THE GEOS-Generic Library 21 JULY 2005

GEOS-5 ESMF DESIGN In GEOS-5 we chose to use a fine-grain component design –– ESMF components are used down to the parameterization level; they must therefore be fairly light-weight. We use a hierarchical topology, using Composite Components, and so we are concerned with the relations (couplings) between parents and children, and between siblings, cousins, etc.

Composite Components Composite Components (CCs) are ESMF Gridded Components GCs) that can spawn instances of other components by having USE association to their SetServices methods. CCs create instances of their children, declare their import and export states, and control the execution of their ESMF registered methods. Further, since CCs own the children’s import and export states, they can move data amongst them. They can thus serve “couplers”

Composite Components The children actually instanciated by a CC and the number of instances of each can be dynamic––it is decided when the CC’s SetServices is invoked and can be controlled from a resource file. In particular, the number of instances of a child can be zero. Invoking the CC’s SetServices or any of its ESMF- registered methods, invokes them in all instances of its children and in all their progeny.

Composite Components In ESMF, GCs can be created with an optional grid and configuration specified by the parent. All GEOS-5 GCs expect to inherit both a grid and a configuration. The inherited configuration is treated in GEOS-5 analogously to the environment in Unix.

Hierarchical Component Structure BASE COMPONENTS COMPOSITE COMPONENTS (“physical” Couplers) “Cap” Small, light-weight gridded components based on GEOS_Generic services “True” couplers Can be generic ESMF Gridded Component ESMF Coupler Component

GEOS-5 AGCM COMPONENT STRUCTURE AGCM DYNAMICS GWDFVCORE RADIATION COLUMN PHYSICS SOLAR IR MOIST TURB SURFACE CHEM LAKE OCEAN CAP (qv, ql, qi, cl,…) (u, v, T, p) (Tc, qc, Td,...) (Ts,Fi...) VEGDYN CATCH HISTORY ICE LAND (Ts,Fi...)

AGCM DYNAMICS GWDFVCORE RADIATION COLUMN PHYSICS SOLAR IR MOIST TURB SURFACE CHEM LANDLAKE DATA OCEAN CAP (qv, ql, qi, cl,…) (u, v, T, p) (ro3,…) (Tc, qc, Td,...) (Ts,Fi...) CAP SURFACE SINGLE-COLUMN MODEL DYNAMICS

GEOS-5 AGCM COMPONENT STRUCTURE AGCM RADIATION COLUMN PHYSICS SOLAR IR MOIST TURB SURFACE CHEM LAKE OCEAN DYNAMICS GWDFVCORE CAP (Tc, qc, Td,...) (Ts,Fi...) VEGDYN CATCH HISTORY ICE LAND (Ts,Fi...) SURFACE DYNAMICS

GEOS-5 AGCM COMPONENT STRUCTURE AGCM RADIATION COLUMN PHYSICS SOLAR IR MOIST TURB SURFACE CHEM LAKE OCEAN DYNAMICS GWDFVCORE CAP (Tc, qc, Td,...) (Ts,Fi...) VEGDYN CATCH HISTORY ICE LAND (Ts,Fi...) SURFACE DYNAMICS

GEOS-5 COUPLED MODEL STRUCTURE AGCM CAP HISTORY RADIATION COLUMN PHYSICS SOLAR IR MOIST TURB SURFACE CHEM LAKE OCEAN DYNAMICS GWDFVCORE (Ts,Fi...) VEGDYN CATCH ICE LAND (Ts,Fi...) SURFACE DYNAMICS AGCM COUPLED OGCM

GEOS-5 Stand-Alone Ocean AGCM CAP HISTORY RADIATION COLUMN PHYSICS SOLAR IR MOIST TURB SURFACE CHEM LAKE OCEAN DYNAMICS GWDFVCORE (Ts,Fi...) VEGDYN CATCH ICE LAND (Ts,Fi...) SURFACE DYNAMICS AGCM COUPLED OGCM Poseidon OBIO

GEOS-5 Ocean DAS AGCM CAP HISTORY RADIATION COLUMN PHYSICS SOLAR IR MOIST TURB SURFACE CHEM LAKE OCEAN DYNAMICS GWDFVCORE (Ts,Fi...) VEGDYN CATCH ICE LAND (Ts,Fi...) SURFACE DYNAMICS AGCM COUPLED OGCM AGCM

GEOS Generic

GEOS-GENERIC EXTENSIONS Three major extensions of ESMF concepts: –GEOS Generic provides default Initialize, Run, and Finalize methods and a Generic SetServices to do ESMF “boilerplate” –In GEOS Generic, SetServices is extended to provide data and connectivity services. –GEOS Generic defines an Internal State

Inside an Instance of a GC ESMF Gridded Component Grid Config - User Internal State(s) - - GEOS_Generic Object -”ESMF” Internal State

GEOS-GENERIC EXTENSIONS Three major extensions of ESMF concepts: –GEOS Generic provides default Initialize, Run, and Finalize methods and a Generic SetServices to do ESMF “boilerplate” –In GEOS Generic, SetServices is extended to provide data and connectivity services. –GEOS Generic defines an Internal State

DATA SERVICES AND THE THREE STATES Data services allow you to describe your import, export and internal states, giving each variable attributes like names, units, dimensionality, usage attributes, grid associations, etc. Import states are read only to you. Export states are read only to others. This allows the passing of pointers rather than copies and so lightens the coupling. GEOS Generic creates, allocates and initializes, as appropriate, variables in all three states, putting them in ESMF classes (Arrays, Fields, Bundles, States) that are used by the infrastructure. Import and Internal states are optionally checkpointed and restarted by Generic Initialize and Generic Finalize.

CONNECTIVITY SERVICES The connectivity services include: – declaration of children – control of how child’s and self’s imports and exports are connected to each other and to the outside –declaration of special “friendly” relationships between components that must operate on large or open- ended sets of state variables, etc. –Restrictions apply.

RADIATION COLUMN PHYSICS SOLAR IR CAP MOIST TURBCHEM Exports are passed up from child to parent, until they reach the cap, where they can be written out. Children’s imports are satisfied among by siblings or added to parent’s imports, until the reach the cap. HISTORY

GEOS-GENERIC EXTENSIONS Three major extensions of ESMF concepts: –GEOS Generic provides default Initialize, Run, and Finalize methods and a Generic SetServices to do ESMF “boilerplate” –In GEOS Generic, SetServices is extended to provide data and connectivity services. –GEOS Generic defines an Internal State

module GEOS_DummyGridCompMod use GEOS_Mod, only :: GEOS_GenericSetServices end module GEOS_DummyGridCompMod AN ESMF GRIDDED COMPONENT

module GEOS_GridCompMod use ESMF_Mod use GEOS_Mod implicit none private public SetServices contains Subroutine SetServices(GC,RC) type(ESMF_GridComp), intent(INOUT) :: GC integer, optional, intent(OUT) :: RC call GEOS_GenericSetServices ( GC, RC ) call ESMF_GridCompSetEntryPoint ( GC, ESMF_SETRUN, Run, & ESMF_SINGLEPHASE, RC) ! Do data services ! Do connectivity services End subroutine SetServices Subroutine Run(GC…. ! Do your work End subroutine Run End module GEOS_GridCompMod

SUMMARY GEOS-5 is a modeling and assimilation system based on many ESMF gridded components. It uses a highly configurable hierarchical architecture It relies on an implementation layer (GEOS-Generic) to facilitate the construction and coupling of the ESMF GCs.