GO-ESSP The Earth System Grid The Challenges of Building Web Client Geo-Spatial Applications Eric Nienhouse NCAR

GO-ESSP Outline A Case Study of UI Development  Brief Overview of the Earth System Grid  Focus on User Interface for Visualization  Present User Feedback and Technical Challenges  Consider Next Steps in UI Development

GO-ESSP What is the Earth System Grid? Distributed System of Gateways and Data Nodes  Access Control and User Management  RDF Metadata Search  Data Access and Download  Collection Browsing  Collection Tagging and Annotation  Deep Storage Data Transfer and Monitoring  Visualization and Data Products  Model Comparison  Use Metrics and Reporting

GO-ESSP User Interface for Visualization Basic Requirements  Provide ability to visually identify data of interest  Usable by wide range of technical abilities  Support future needs of comparison and sub-setting  Integrate with gateway context and look and feel  Flexible enough to adapt to new backend services  Functional enough to generate feedback

GO-ESSP User Interface for Visualization Alpha Process: How We Started  Lightweight client based on JavaScript/Ajax  Use Live Access Server to deliver visualization  OpenDAP and aggregation capabilities of TDS  Develop within Java/Spring gateway framework  Use known Google Maps API

GO-ESSP User Interface for Visualization Initial Prototype: Google Map API Custom selection overlay Dojo JavaScript Toolkit Tree based selection Ajax application with JSON Proxy client to access LAS LAS Armstrong v 0.4 TDS v 3.16

GO-ESSP Component Communication Proxy Client: Request pass through to LAS Avoid browser security Augments LAS capabilities Preserves gateway context Allows Flexibility

GO-ESSP Initial Prototype: Feedback and Lessons Learned: Single page UI is an improvement over wizard Screen real estate must be used wisely Tree based UI tedious for some User reset of region is critical for usability Visualization tools excite people and yield feedback People look closely at dataset and variable names Visualization helps identify data problems Dojo toolkit is good but poorly documented TDS aggregations + LAS is a powerful combination Configuration of TDS and LAS must be automated

GO-ESSP User Interface for Visualization Back to the Drawing Board: Review of feedback Wire-frame drawings Basic formal specification

GO-ESSP User Interface for Visualization Second Prototype: YUI user interface Improved real estate use Improved state indication Pre initialized dataset and variable Ajax application with JSON Proxy client access to LAS Place holder for sub-setting UI LAS V7 Beta F-TDS v 3.16

GO-ESSP Second Prototype: Feedback and Lessons Learned: Differing communities have diverse abilities Modeling community prefers to access data directly Simplified work flows needed for some user groups Combine selection and presentation UI for efficiency Averaging and analysis functions are desired by many Plot legends, times and source data labels are important Variable names must be consistent TDS + NcML critical in making data “visualize-able” Delayed delivery is important consideration for UI Saving regions of interest and product result are desired Polar projections unlikely to be supported by Google Maps Firebug extremely useful debugging tool JavaScript frameworks produce browser incompatibilities

GO-ESSP Next Steps: What will we do with these findings? Collect more feedback from ESG test-bed deployment. Consider formalizing user studies and observations Expose more analysis features of LAS Add multi-variable selection for analysis, sub-setting, layering Integrate geographic selection with search tools Explore more “polar capable” UI components Explore WMS visualization capabilities Exploit more of the F-TDS analysis, sub-setting capabilities Continue to refine and improve quality of the UI Encourage community convergence on UI best practices

GO-ESSP Thank You! In particular: Ansley Manke, PMEL Roland Schweitzer, PMEL John Caron, UNIDATA Collaborators at ANL, LBNL, PCMDI and many others…

GO-ESSP Questions?