Developing Understanding of Ecological Economic SystemsThomas MaxwellRobert Costanza University of Maryland

MotivationUnbridled expansion of human enterprise.Depletion of natural life support systems.Resource depletion -> global tensions.Interacting complex systems.Tremendous uncertainty.Potentially disastrous consequences.

Integrated Problem SolvingVisionState of the world.Possible future worlds (postitive & negative).What to tweak?Expected outcomes of policy adjustments.MethodologyHard problem science.Adaptive management.

Science in Service of SocietyComprehensive systems approachConceptual pluralismProblem driverMultiscaleIntegrated modelingLinks with policyModeling as consensus building toolCommunicating uncertainty

Collaborative (Visible) ModelingRealistic models require multiple teamsModelers typically not computer scientistsStake holders must be includedCommunication to a wide audience

Three Stage Modeling ProcessScoping modelsConsensus buildingResearch modelsUnderstanding dynamicsManagement modelsExploring scenarios

Modeling CollaboratoryConstructivist learning.Paradigm expansion.(narrow,linear,static) ->(broad,nonlinear,dynamic)Conflict resolution.Consensus building.Collective decision making.Develop management scenarios.

Supporting Collaborative ModelingGraphical modeling toolsModular model developmentTransparent high performance computingIntegrated data accessIntegrated visualizationVariety of formalisms and frames

Graphical ModelingModel viewed and manipulated graphically.Opens model development to non-programmers.Facilitates rapid development of models.Enforces modeling standards.Facilitates collaboration in model development.Graphical representation serves as a blackboard.

STELLA Model

Spatial Modeling Framework

CavernSoftCollaborativeEnvironmentEnvironmental Hydrology Applications TeamInputs to multiple models

Environmental Modeling Workbench

Integrated wirelessSensor webCoupledBio-HydroSimulationSpatial Modeling Environment

Two types of modulesEcological ModulesNo general theory.Primary focus on modeling.Examples: Macrophytes, Epiphytes, Consumers, PhytoplanktonModules developed in Stella/SME.

Physical ModulesTheory well known (e.g. Navier Stokes).Primary focus on computation.Examples: hydrodynamics, atmospheric dynamics.Modules developed externally and linked to SME.

Spatial Modeling Environment Collaborative Spatial Modeling Workbench Includes integrated support for:Icon-based unit module developmentModule archiving and reuseIntegration of multiple spatial representationsDistributed computingWeb-based modeling & simulationConfiguration, control, and visualization of remote simulations.Data access and visualizationReal-time links to other apps (e.g. Swarm).

Spatial Modeling EnvironmentSTELLA

PowerSim

SME ModuleEditorModuleConstructorSMML Module LibraryModuleRepositoryModuleBuilderSimulationDriverCode GeneratorHPCJavaPortalUnit modelSpatial modelGraphical modeling

Module Specification LanguageDeclarativeModularFully visible structure & dynamicsSupports encapsulation and specializationSeparate universal specs / site-specific configsPlatform and operating system independentFacilitates extensive simulation services

Simulation Module Markup Language XML-Based Declarative Language Simulation Module Specification Major Classes:Module: Reusable component.Variable: Simulation atomic object.Action: Performs computation or data IO.Event: Orders the execution of Actions.Frame: Defines a spatial topology.

( ( ( CONS_INGEST-CONS_EGEST )-CONS_MORT_BIOM ) ) CONS_RESPIRATION )

CARBON BIOMASS OF AN AGGREGATED CONSUMER. (KGC). CONSUMERS EXCLUDE THE MICRO ORGANISMS WHICH ARE ACCOUNTED FOR IN THE RESPIRATION FLUXES ( ( P1_CONS_IC*0.001 )*CELL_SIZE )

SMML Example

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SMML Example

Typical State VariablesExamples of some typical state variables:(Dissolved Inorganic) Nitrogen, Phosphorus Water (Saturated, Unsaturated, Surface, Snow)DetritusMacrophyte (Non)Photosynthetic BiomassConsumersDeposited Organic MatterPhytoplanktonEpiphytes

Agent Based Modeling in SMESwarm agents can populate SME landscapes.SME-Swarm integration:http://iee.umces.edu/~villa/swarmsmeSwarm classes serve as wrappers for:SME model.SME grid layers.SME spatial variables.Two-way remote data transfer.Built on SNI simulation server architecture:http://iee.umces.edu/~villa/sni

Multi-Grid LibraryIntegrates multiple spatial representations Implements space in SME Major Components include:Cell: Spatially referenced area (or volume) element.Grid: Distributed set of Cells + links.Frame: Hierarchy of distributed Grids.Link: Connection between Cells.Intra-Grid: spatial contiguity.Inter-grid: scaling relations or mappings.Activation Layer: Subset of Cells in a Frame.Coverage: Mapping:: Activation Layer -> floats.

Spatial grid partitioned over processors

Highly parallel application

Recursive N-section: excellent load balancing

Fully transparent to userDistributed Processing

Model Calibration toolkitBuilt on MPE toolkit:http://iee.umces.edu/~villa/svp/Calculate performance measure (MPE)Estimate of match between model & system.Weighted sum of tests (Bounds, Theil, Freq, etc).Search parameter space to maximize MPE.Evolutionary and gradient searches.Params, tests, & searches configured in SME.

SME Java PortalDesktop access to remote supercomputing resourcesWeb-enabled ( using java servlets )Grid enabled ( using globus gram utility )Java applet Java servlet C++ appsPortal interfaces include:Workspace managementModule developmentModel configurationSimulation initialization, control, & visualization

WorkSpace Manager

Documentation PanelDocumentation of selected command

Model PanelHierarchical View of model objectsAssociated commands as boxes

Command PanelStructure of selected command

Property Panel Command ArgumentsConfiguration Manager

Parameter EditorEdit Simulation Parameters

Spreadsheet format

Simulation Control Control Execution View Model Structure Trace Dependencies View Model Equations Configure Visualization

Associates DataSets with Viewers

Creates Viewers

Manages DataSets

ViewServer Control Panel

2D Animation Viewer2D Animation Control Dynamic and manual rescaling ColorMap editor Data viewer (point/spreadsheet) Export as GIF or JPG

3D Animation ViewerDynamic Landscapes Variable1 -> Altitude Variable2 -> Color Mouse controlled navigation

Image Spreadsheet Simultaneous display of variables at multiple timesteps Useful for time series comparisons Configure: start time, time step, magnification, scaling, etc.

View spatial data Attach to vis panels Follows animation Export to Stat packages.Numerical Spreadsheet

Links components: Circulation (OM3) Ecology (SME)Atmospheric coupling Environmental Hydrology Applications TeamChesapeake Bay Model

Collaborative Virtual EnvironmentEnvironmental Hydrology Applications TeamChesapeake Bay data in CVE with Cave5D/Virtual Director

Example ApplicationsEverglades Landscape Modelhttp://www.sfwmd.gov/org/erd/esr/elm/intro/welcome.htmPatuxent Landscape Modelhttp://iee.umces.edu/PLMBaltimore Ecosystem Studyhttp://baltimore.umbc.edu/lterIllinois TES Modelshttp://blizzard.gis.uiuc.edu/

Environmental HydrologyEnvironmental Hydrology Applications Team

SME Distribution The SME home page:

http://iee.umces.edu/SME3

Includes:Overview.Technical documentation.Publications.Source code (C++ and java).Links