There is increasing evidence that intercontinental transport of air pollutants is substantial Currently, chemical transport models are the main tools for estimating hemispheric transport Two key pollutants are fine particles composed of sulfates, organics, dust, etc., and ozone The models indicate that East Asia impacts North America, which in turn impacts on Europe. Use Case #2: Hemispheric Transport of Air Pollutants (HTAP) Science goal: Estimate impact of one continent on another for major pollutants Policy question: Should there be a global-scale protocol to manage HTAP? This demo illustrates analyses that are being performed for the HTAP Task Force. SulfateOrganics

In the European AeroCom project led by, Michael Schulz, over 20 global aerosol models developed in many countries, are compared to each other. For each model, the simulations are averaged over a season or a full year. The results indicate considerable model-to-model deviation, even for sulfate simulations. The AeroCom information system applied considerable human and computer effort to homogenize the model inputs. The models are evaluated by comparing models-to-models and models to observations These comparisons establish the level of confidence in the validity of the model estimates. Diverse Model Simulations Model-to-Model Comparisons

Global-scale surface monitoring data for aerosol species are sparse and uneven. However, extensive speciated aerosol data over the U.S. allows partial validation of global models. The VIEWS system integrates and homogenizes the speciated monitoring data from multiple networks. Model-Data Comparison The average surface concentration measured at 300+ monitors can be compared to model values. In the above model-data comparison, the spatial pattern are similar for both aerosol sulfate and organics. However, they deviate in the absolute magnitude. Hence, additional model development and model-data comparisons are recommended. Organics Sulfate

Information System for Model-Data Comparison Using the DataFed Web Service-Based Workflow Software Web Service Flow Program Data access is performed through OGC standard services, WMS and WCS. The processing and rendering is executed through web service chaining at the DataFed server. WMS, WCS OGC Services AeroCom Chemical Models VIEWS Chemical Data Models Monitoring Networks CAPITA Model- Data Comparison Model (images) and VIEWS observations (SQL database) are accessed online from Paris and Ft. Collins respectively. Both in AeroCom and VIEWS systems the data are homogenized and shared through their respective “portals” At DataFed, the observations are averaged through an aggregation service and rendered on top of the model. When gridded model data become available, the model-data will be compared through numerical algorithms.

Model-Data Information System – Stovepipe AeroCom Chemical Models VIEWS Chemical Data Models Monitoring Data CAPITA Model- Data Comparison The model, observational data, and processing services can be used in multiple configurations: “stovepipe” open federated In a dedicated “stovepipe” implementation, the result of the model-data comparison is exposed. However, the internals of the processing are hard-coded within the processing system

Model-Data Information System - Open In an open system, the component data and processes are exposed for sharing. This allows model-data comparisons to be performed by the collaborating organizations as well as others familiar with the data and service interfaces. Internet AeroCom Chemical Models VIEWS Chemical Data Models Monitoring Data CAPITA Model- Data Comparison

Model-Data Information System - Federation VIEWS AeroCom Federated Information System Observations, Models, Services CAPITA Other Federations Obs Models Obs & Services Services Obs & Model Models & Services General data sharing and reuse can be accomplished through a federated approach. Data producers maintain their own workspace and resources (data, reports, comments). However, part of the resources are shared through a Federated Information System. In a Federation all of the data, as well as the processing services apply standard interfaces. In a Federation, loosely coupled components can be combined into agile analysis systems.

DSS for HTAP Policy Decisions Observations HTAP Knowledge into the Minds of Policy Analysts HTAP Reports: Model Estimates, Obs. Evidence Models Knowledge into the Minds of AQ Analysts Decisions HTAP Knowledge into the Minds of Policy Makers Decision Support System GEOSS Architecture Framework

GEOSS and National/Regional Air Quality Assessment GEOSS GlobalLocal Air Quality Benefit Global data, tools => Broader context, cost savings Global analysis => Spatial context, Characterization Intellectual Resources => Collaboration, Analysis Regional GEOSS Benefit Local data, tools => Enriched global resource pool Local data analysis => More detail, insights, Intellectual Resources => Collaboration, Analysis The GEOSS global view establishes the larger-scale context Regional perspective focuses on the detailed characterization of local features AQ data analysis needs to be performed at both through GEOSS and regional programs GEOSS Information Architecture needs to support global-regional information exchange.

Acknowledgements The Global Model-Data Comparison is based on model data prepared by the European AeroCom Aerosol Model Comparison project. The aerosol chemical data over the US were integrated and provided to the DataFed federation through the VIEWS system. It is hoped that such international collaboration can be expanded and intensified through GEOSS.AeroCom Aerosol Model Comparison projectVIEWS system