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Gulf of Maine Circulation Modeling: Prospects for Skill 6 July 2005. Daniel R. Lynch Dartmouth College Hanover NH. Points of Departure. Science People Data Problems. Science. Well-Established: Physical Quantities Equations Algorithms for solutions. Distributed across ‘Academe’.
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Gulf of Maine Circulation Modeling: Prospects for Skill6 July 2005 Daniel R. LynchDartmouth CollegeHanover NH
Points of Departure • Science • People • Data • Problems
Science • Well-Established: • Physical Quantities • Equations • Algorithms for solutions • Distributed across ‘Academe’
People • At least 3 different communities • Theory • Observation • Simulation “the third science” • Algorithms • Systems • Non-Local • Incentives: Advancement of Learning
Data • Unprecedented new abundance • Sampling in (x, y, z, t) necessarily sparse • Real Data is site-specific, event-specific • Necessary to relate theory to facts • By itself, hopelessly incomplete • Interpolation • Extrapolation • Interpretation • Relation to other information
Problems • “Local” • Not alligned with political boundaries • Distributed across agencies • Regulatory context
Status Quo • Science: generic, roaming • Data: local, incomplete • People: distributed across ‘academe’ • Advancent of knowledge, not application • Problems: regulatory context, local, political boundaries The Key Challenge is Organizational
Regional Progress • 1993 RARGOM Workshop <------------- • RMRP • MWRA Mass. Bays • GLOBEC • EcoHAB • Sea Grant (x4) • GoMOOS • Multiple NOAA programs • Canadian Companions
Time of Occurrence (Ocean) State Estimation Future (Now) Past Time of Availability (Information)
Time of Occurrence (Ocean) Forecast Nowcast Hindcast Time of Availability (Information)
Time of Occurrence (Ocean) Forecast Nowcast Hindcast All Data Time of Availability (Information)
Time of Occurrence (Ocean) Forecast Nowcast Hindcast All Data Time of Availability (Information)
Time of Occurrence (Ocean) Forecast Model ‘Data Product’ Nowcast All Data Hindcast Time of Availability (Information)
Time of Occurrence (Ocean) Forecast Nowcast Hindcast Data Used Bell Time of Availability (Information)
Time of Occurrence (Ocean) Forecast Nowcast Hindcast Data Used Bell Publication Time of Availability (Information)
Theory “The Data” Necessary and Sufficient initial state, simultaneous boundary conditions (deep ocean, cross-shelf transports) forcing (atmospheric fluxes, rivers) Parameters (bottom, surface roughness) All roads lead to Rome (small DX) The Well-Posed Problem(The Mathematical Standard)
Theory “The Data” Necessary and Sufficient initial state, simultaneous boundary conditions (deep ocean, cross-shelf transports) forcing (atmospheric fluxes, rivers) Parameters (bottom, surface roughness) All roads lead to Rome (small DX) Actual The Well-Posed Problem(The Mathematical Standard) Nonnecessary Insufficient DX is finite
Theory “The Data” Necessary and Sufficient initial state, simultaneous boundary conditions (deep ocean, cross-shelf transports) forcing (atmospheric fluxes, rivers) Parameters (bottom, surface roughness) All roads lead to Rome (small DX) Actual The Well-Posed Problem(The Mathematical Standard) Nonnecessary Insufficient DX is finite There is never a well-posed problem in nature
Poorly Posed Problems • Must make up what is not known but necessary • Use the data you have, deduce what you need • Criterion: credibility • Credibility implies a Prior Estimate • mean and variance
What is Truth? ed em Data Model Misfit d
What is Truth? ep ed em Prediction Data Model Misfit d Truth real but unknowable Errors unknowable Prediction a credible blend: Data + Model Blend: Invokes statistics of ed , em Prediction Error: blend of statistics of ed , em, d
What is Truth? ep ed em Prediction Data Model Misfit d Skill: Misfits Small, Noisy Unknown Inputs Small, Smooth ep : grows with time Truth real but unknowable Errors unknowable Prediction a credible blend: Data + Model Blend: Invokes statistics of ed , emd
Examples • SAB: resolve the data or burn it • Great Bay: Hi-resolution Lagrangian exchange • ECOHAB Results: hindcast trajectories • Georges Bank: Real-time Wind Forecast Error
The difference between high-resolution and low-resolution forward simulations
Inverse Error with Low Resolution-- DA cannot make up for Inadequate Resolution --
The 2005 Hindcast • Data-Assimilative • Real Time • At-Sea • Limited-area • Hindcast of complete cruise • May 9- 18
Key Challenges Organizational
Recommendations • Accept • Organizational progress must occur • Scientific progress must continue in parallel • Modeling is its own ‘science’ • Focus on • the modelers, not the tools • energizing the science community • do not try to change the scientific culture • organize the use of the Gulf of Maine as a laboratory • enabling scientific progress on practical problems • Circulation Modeling as initial baseline • Invent • no new organizations • one new task: “Gulf of Maine Modeling Roundtable” • Insist on its ‘standing’ in science and regulatory communities • Do not distort the University Mission - Announce a new one • Expect to Pay and Get