EUMETSAT EO Portal End User Image Access using OGC WMS/WCS services Slide: 1
Overview Introduction: status of data access and visualization EUMETSAT datasets Architecture Web Map Service implementation Web Coverage Service implementation Future work Slide: 2
Data access Current status: High quality products only available via ordering or subscription Project goal: Make products available via standardized Web Service interfaces (WMS/WCS) Advantages: On-demand real time access to data Many Desktop or Web GIS have integrated support for this interface Lower effort on provider side (fewer orders) Slide: 3
Data Visualization Current status: animated preview images of fixed areas available on EUMETSAT portal Project goal: make products available using standard interfaces, via layers of Web Map Service (WMS) interface Advantages: Dynamic maps retain: native resolution, data values, georeferencing information Generation of images for selected area of interest on-the-fly Most Desktop and Web GIS support this interface Images can be overlaid with data from different sources (local, Web) to generate custom maps Slide: 4
Current Approach Slide: 5
EUMETSAT data EUMETSAT datasets available in the following formats: netcdf GRIB BUFR HDF5 These formats generally lack broad support in current WMS/WCS implementations 2-D coordinate axes of EUMETSAT s netcdf files were often not understood by netcdf clients Alternative: Transform datasets to GeoTIFF format (Cinesat) Slide: 6
Architecture Alternatives A Cinesat Write transformed datasets GeoTIFF database Conventional Data Server WCS Conventional Map Server WMS EUMETSAT Archive netcdf/bufr/ GRIB THREDDS WCS B netcdf/ BUFR/GRIB database ncwms WMS Slide: 7
First WMS Prototype ncwms (Architecture Alternative B) Pros: Open source WMS 1.3 with time dimensions Support for netcdf datasets (+GRIB/HDF5) Support for animated maps (by selected time range) Cons: Poor performance for our datasets (knock-out criterion) Small user base No GeoTIFF support Slide: 8
Performance Evaluation Compare first prototype (ncwms) to other WMS 2 test scenarios, tiled and untiled map 10 concurrent users, 10 requests each, run 10 times Tiled map Untiled map ncwms (GeoTIFF) 36 min. 10:46 min. ncwms (netcdf) 60 min. 18 min. GeoServer (GeoTIFF) 2:44 min. 3:22 min. UMN Mapserver 5:16 min. 2:54 min. Results led to a second prototype based on GeoServer Slide: 9
Current WMS Prototype - Server GeoServer (Architecture alternative A) Pros: Open source WMS with large user base Better performance with several optimization options Integrated WCS support for all available datasets Cons: So far no out-of-the-box support for netcdf/grib No support for WMS 1.3 with time dimension Slide: 10
Current WMS Prototype -Development In development: GeoServer Extension to handle time dimension WMS 1.3.0 w/time request / response WMS 1.3 Facade WMS 1.1.1 request / response Standard GeoServer Client (GWT + OpenLayers) Custom WMS client: Based on OpenLayers (open source JavaScipt library) Developed with Google Web Toolkit maps time to individual datesets GeoTIFF Time series Slide: 11
Prototype deployed in Cloud Prototype presently running in AMAZON EC2 Standard Large Instance (OpenSolaris AMI) 7.5 GB memory 4 EC2 Compute Units (2 virtual cores with 2 EC2 Compute Units each) 850 GB instance storage (2 420 GB plus 10 GB root partition) 64-bit platform I/O Performance: High API name: m1.large Slide: 12
Current WMS Prototype - Client Slide: 13
AIRMASS loaded in Google Earth Slide: 14
External Background Layer Slide: 15
http://veoportal.eumetsat.int/mapviewer Slide: 17