HR-DDS and Pilot Wave Forecast Verification Scheme Extension Interactive on-demand analysis David Poulter, National Oceanography Centre GlobWave 2010. All rights reserved
The Globwave HR-DDS The GlobWave HR-What?? The High Resolution Diagnostic Data Set Before we begin. The GlobWave HR-DDS will not be operational before mid- September 2010, some of the figures in this presentation are from the already operational SST HR-DDS No. 2
A bit of history The HR-DDS evolved as a service for satellite SST providers (the space agencies themselves) Intended to fill the gap between validation schemes Individual pixels (1km) Spatial Scale Global scale HR-DDS No. 3
The Globwave HR-DDS An online archive of small subsets of data, extracted every time an observation is made over one of a series of sites User configurable locations where data are extracted Individual points for spectral inter-comparisons Automatic content ingestion with scope for experimental data / prototype feeds Any bi-polar projection and configurable resolution No. 4
The Globwave HR-DDS What happens next? Archive is linked to a very fast database containing statistical representation of each extraction. An example from the SST HR-DDS for mean temperatures at a site in the Mediterranean. No. 5
The Globwave HR-DDS Further analysis Each element in the database is linked to the original data and can quickly be viewed or compared. No. 6
Some examples Identifying the cause of gross errors in METOP-A SSTs at high latitudes METOP-A AVHRR gave an apparently geophysical error unseen by other instruments No. 7
The Globwave HR-DDS Archive of subsets Interactive selection tools for data collection (i.e. date, quality level, product type) Statistical data collection (CSV values from time-series, etc) Download a tarball of the granules / products you are looking at Diagnostic tool Search for worst match-ups Get automatic reports (RSS / email / webpage) revealing the performance of a model test run as satellite data becomes available Metrics reporting We can provide gross error checking reports automatically Or monthly reports of data availability, download times etc No. 8
The Globwave HR-DDS Wave data is not like SST! Wave data are far more complicated than SST! (Forecasts, spectra) However Satellite data is 1D or point sample The far lower data volume means we can keep a far higher proportion of the data. Possibly even 100% of the data for the recent record Spectral data is available We implement a common partitioning scheme for all spectral data provided Derived parameters are stored along with the spectra for each partition Forecast data is typical We have two time dimensions for inter-comparison No. 9
The Globwave HR-DDS What about waves? Waves present some challenges and opportunities! The far lower data volume means we can keep a far higher proportion of the data. No. 10
The Globwave HR-DDS Contents and Timeline All GlobWave satellite products Altimeter L2P products (GeoSat, GFO, Jason-1, Jason-2, T/P, Envisat, ERS1, ERS2) SAR L2P products (ERS1, ERS2, Envisat) Model data as provided. The SST HR-DDS already records some wave parameters in prototype The HR-DDS will be operational for NRT satellite data in mid September Rolling ingestion of GDR data after that No. 11
The Globwave WFVS The GlobWave Pilot Wave Forecast Verification Scheme A pilot spatial and spectral extension to the JCOMM wave forecast verification scheme operated at ECMWF No. 12
The JCOMM WFVS Routine inter-comparison of global wave model forecast verification data Established in 1995 To provide quality assurance for wave forecast model products In particular for SOLAS, ship routing and the GMDSS Continued under the auspices of ETWS Original inter-comparison Exchange of model forecast data at moored buoy sites Observations of sig. wave height, wave period and wind speed via WMO GTS Five centres involved Exchange subsequently expanded Paper discussing results from the exchange was published in 2002 No. 13
The JCOMM WFVS Thirteen centres participating ECMWF, Met Office, FNMOC, NCEP, Meterological Service of Canada, Météo-France, DWD, BOM, SHOM, JMA, Puertos del Estados, KMA Statistics produced monthly at ECMWF Bias RMS errors Correlation coefficient Scatter index Symmetric slope Each statistic produced for Significant wave height Peak period No. 14
The JCOMM WFVS Plots are produced for Statistics as a function of forecast lead time Time series of model and observation values Scatter plots of model vs observation values Verification data sets also available to allow further calculation Statistics made available on a web page for those centres involved in the exchange Contribute to on-going validation efforts A common set of observations is used Data is exchanged in an agreed common format Scatter and time-series plots No. 15
The JCOMM WFVS The existing WFVS is an invaluable tool It does however have some limitations: Only one one common report is produced No. 16
The Globwave WFVS GlobWave is providing an extension to the existing service It will extend the inter-comparison To the spatial domain as regional / global comparison of model fields Spectral inter-comparison It will provide various analysis options Model to model (forecast forecast / nowcast nowcast) Model forecasts to their own later nowcasts Model to satellite Model to ensemble model result Accept data in many formats NetCDF / GRIB model dumps (BUFR if needed) ASCII time series ASCII spectral outputs No. 17
The Globwave WFVS A website will be provided to configure the reports: Which regions to include Which comparisons to perform Which report sections to provide Available March 2011 Reports are guaranteed to be delivered once per month By day 10 of the next month We may be able to maintain a latest report much more frequently Report will be linked to the HR-DDS Each image in the PDF will be an HTML link the the same analysis on the website You could click on a report image and then change details of it online No. 18
The Globwave WFVS Some examples: No. 19
The Globwave WFVS Some examples: No. 20
The Globwave WFVS Some examples: No. 21
The Globwave WFVS Some examples: No. 22
Questions 07 May 2010 No. 23