Cimatoribus, Andrea

Infoscience - École polytechnique fédérale de Lausanne

Use cases Issues OutlookCOSMO for lake studies: use cases andcriticalities in a scientific environmentAndrea CimatoribusEcological Engineering LaboratoryÉcole polythechnique fédérale de LausanneJanuary 30, 2017Andrea Cimatoribus | COSMO@LacLéman 1/26Use cases Issues OutlookTable of contents1 Use casesForcing of hydrodynamic models (T. Baracchini)Estimation of air–water fluxes (A. Irani Rahaghi)Summary2 IssuesValidation over water bodiesTemporal and spatial resolutionSummary3 OutlookValidation eﬀortCouplingAndrea Cimatoribus | COSMO@LacLéman 2/26Use cases Issues OutlookTable of Contents1 Use casesForcing of hydrodynamic models (T. Baracchini)Estimation of air–water fluxes (A. Irani Rahaghi)Summary2 IssuesValidation over water bodiesTemporal and spatial resolutionSummary3 OutlookValidation eﬀortCouplingAndrea Cimatoribus | COSMO@LacLéman 3/26Use cases Issues Outlook.A comprehensive frameworkfor lakes modelling and monitoring.. meteolakes.epfl.chTheo BaracchiniA. J. Wüest, D. BouﬀardAPHYS – EPFLAndrea Cimatoribus | COSMO@LacLéman 4/26IntroductionCORESIM – ESA projectThe current challenge is to combine those sources to provide  timely, scientifically credible, and policy-relevant environmental information Interlink of the 3 information sourcesProvide a modelling framework tailored to inland waters: Operational in real-time With short-term forecasting Online, open to the public Benefiting/applied to aquatic research By studying mesoscale processes (e.g. upwellings) And assessing the variability of lake responses to climate change2BathymetryGrid300 200 100 (m)Background simulationModel setupDelft3D model set-up: Z-layer, 100 layers < 450m horizontal grid size 1 min simulation time step Calibrated and validated with in-situ and remote sensing  Real time validation with AVHRR satellites and in-situ monitoring station13 km3Wind fieldEx: typical synoptical windBackground simulationSpace-time varying forcingMeteorological forcing (MétéoSuisse’s COSMO-1 & COSMO-E): 7 Variables Air temperature Air pressure Relative humidity Cloud cover Wind intensity Wind direction Solar radiations On 1.1 km grid (COSMO-1) and 2.2 km (COSMO-E) Every hour4Real-time data collectionIn-situ and meteo station5Buchillon station: 11 sensors Air & water (skin + bulk) temperature Wind direction & intensity Solar radiations ADCP (flow velocity) … High frequency measurements (1/min) GPRS data uplink Openly available onlineReal-time data collectionRemote sensing validation6AVHRR satellite data: Up to 12 overpasses a day 1 km spatial resolution Downlink and processing (skin to bulk) at University of Bern Direct comparison with modelling results for validation Openly available onlineFuture perspectives Inclusion of BAFU river data (available Feb. 2017) Real-time data assimilation (DA)  Ensemble Kalman Filtering AVHRR surface temperature DA Forecasting uncertainties Water quality monitoring Algae concentration, oxygen, plankton species, etc. (available summer 2017) MERIS and Sentinel-2 satellite DA Implementation for other Swiss lakesMeteolakes8Use cases Issues Outlook.Air–water interaction in Lake Geneva..Abolfazl Irani RahaghiD. A. Berry, U. LemminECOL – EPFLAndrea Cimatoribus | COSMO@LacLéman 11/26Use cases Issues OutlookUses of COSMO Forcing field for hydrodynamic numerical model Fill “missing data” (e.g. in bulk formula) Interpretation of field observations Weather prediction for field activitiesAndrea Cimatoribus | COSMO@LacLéman 18/26Use cases Issues OutlookTable of Contents1 Use casesForcing of hydrodynamic models (T. Baracchini)Estimation of air–water fluxes (A. Irani Rahaghi)Summary2 IssuesValidation over water bodiesTemporal and spatial resolutionSummary3 OutlookValidation eﬀortCouplingAndrea Cimatoribus | COSMO@LacLéman 19/26Use cases Issues OutlookValidation of COSMO over lakesHow reliable are COSMO results over Lake Geneva?.dots: MeteoSuisse stations, cross: EPFL stationAndrea Cimatoribus | COSMO@LacLéman 20/26Use cases Issues OutlookValidation of COSMO over lakesHow reliable are COSMO results over Lake Geneva?.Temperature, COSMO2 vs. observations,year 2013Andrea Cimatoribus | COSMO@LacLéman 20/26Use cases Issues OutlookValidation of COSMO over lakesHow reliable are COSMO results over Lake Geneva?.Wind speed, COSMO2 vs. observations,year 2013Andrea Cimatoribus | COSMO@LacLéman 20/26Use cases Issues OutlookValidation of COSMO over lakesHow reliable are COSMO results over Lake Geneva?.Wind speed xcorr,year 2013,observations, modelAndrea Cimatoribus | COSMO@LacLéman 20/26Use cases Issues OutlookHow important is resolution?Is resolution (in space and time) importantin the forcing fields of a hydrodynamic model?.COSMO2 COSMO1September 1, 2016, 21:00Andrea Cimatoribus | COSMO@LacLéman 21/26Use cases Issues OutlookHow important is resolution?Is resolution (in space and time) importantin the forcing fields of a hydrodynamic model?.A hydrodynamic model(MITgcm) forced by hourlyCOSMO2 results is ableto reproduce observedstratification.Andrea Cimatoribus | COSMO@LacLéman 21/26Use cases Issues OutlookHow important is resolution?Is resolution (in space and time) importantin the forcing fields of a hydrodynamic model?.A hydrodynamic model(MITgcm) forced by hourlyCOSMO2 results is ableto reproduce observedstratification. Resolution does not seem to be a limiting factor. . . . . . but are observations suﬃciently resolved?Answer: no.Andrea Cimatoribus | COSMO@LacLéman 21/26Use cases Issues OutlookPossible issues of using COSMO for lake studies Lack of validation above water Over land, the temperature field seems very well constrainedI assume MeteoSuisse temperature measurements are assimilatedin COSMO? For the wind field, the comparison between COSMO andobservation is less clearIs low correlation due to turbulence?Patterns (x-corr) seem to be very well captured The resolution of COSMO results used seems a second orderproblemAndrea Cimatoribus | COSMO@LacLéman 22/26Use cases Issues OutlookTable of Contents1 Use casesForcing of hydrodynamic models (T. Baracchini)Estimation of air–water fluxes (A. Irani Rahaghi)Summary2 IssuesValidation over water bodiesTemporal and spatial resolutionSummary3 OutlookValidation eﬀortCouplingAndrea Cimatoribus | COSMO@LacLéman 23/26Use cases Issues OutlookValidating COSMO over water.Main aims.. Know if/when/where COSMO results can be trusted Separate uncertainty in BC (COSMO) from other uncertaintiesModel errors, parameterisations,. . . Suggest possible improvements to COSMO.Opportunities and issues.. EPFL near shore mast (Buchillon): operationalsee meteolakes.epfl.ch Possibly soon a new platform in the north eastern part of the lake(AJ Wüest) No surface floating buoys are allowed in Lake Geneva Is validation in one lake relevant for other lakes?Andrea Cimatoribus | COSMO@LacLéman 24/26Use cases Issues OutlookCoupling between atmosphere and lakeIs there any advantage in a coupled atmosphere–lake model? A question only for large, deep lakes How important is air–water coupling in a lake?How much heat can be stored and transported in the lake?How does COSMOmodel interaction with lakes? Relevance for convection, both in the atmosphere and in the lake Broader scientific interest: lakes as natural laboratories forair–water interaction Study of small scale turbulent fluctuations at air–water interfaceAndrea Cimatoribus | COSMO@LacLéman 25/26Use cases Issues OutlookSummary. COSMO in lake studies:BC for hydrodynamic modelsestimating air–water fluxesplanning of field campaigns Main issue: unknown reliability over waterWind field in particular Is validation over water feasible? What can we learn by studying the coupled lake–atmospheresystem?Andrea Cimatoribus | COSMO@LacLéman 26/26Use cases Issues OutlookSummary. COSMO in lake studies:BC for hydrodynamic modelsestimating air–water fluxesplanning of field campaigns Main issue: unknown reliability over waterWind field in particular Is validation over water feasible? What can we learn by studying the coupled lake–atmospheresystem?Thank you!andrea.cimatoribus@epfl.chAndrea Cimatoribus | COSMO@LacLéman 26/26

COSMO for lake studies: use cases and criticalities in a scientific environment

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COSMO for lake studies: use cases and criticalities in a scientific environment

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