1. Project Overview

2. Activities

3. Accomplishments And Discussions

3.1 Model

Transition of the 8-bin dust component into NMM-dust was performed by extending the NMM model through the development of an additional dust concentration module. Since the dust component has a similar (mass conserving) structure as, for example, the equation for specific humidity in NMM-dust, dust and specific humidity were handled similarly. They differ in the deposition (source) and emission (sources) as parts specific for dust. These two components were done in a separate routine, following the way of parameterization in the 8-bin code. The two models (8-bin and NMM-dust) are initially tested by comparing to the PHAiRS project's 4-bin code and matched the results in principle. The 8-bin and NMM-dust models are utilized for model interoperability studies and yield good results. Initial tests within the project have been performed with the DREAM-eta 4 bin system (Nickovic et al. 2001). In this system, DREAM model dust particle distribution is described with 4 sizes, ranging in radius from 0.7 - 40 µm. Since the hydrostatic NCEP/Eta cannot be applied with resolution higher than ~ 5km in horizontal, in the next step we replaced the NCEP/Eta with the Nonhydrostatic NCEP/NMM (Janjic et al., 2001) that may be used in a high resolution mode. At the same time NCEP/NMM has a possibility to be run in a parallel execution mode, which is not the case with NCEP/Eta. Theoretical thoughts was made to transfer the DREAM8 component (Nickovic, 2004; Nickovic 2005; Peres et al., 2006) into the NCEP/NMM, DREAM8 being the dust model version that resolves dust particle distribution with 8 particle bins ranging from submicron radius to 10 µm. Smaller particles are used in the project having in mind that such particle size range is more appropriate for possible future use of the modeling system for public health. Incorporating the knowledge gained, we developed the NMM-dust model in the project.

3.2 Interoperability

Through the project, interoperability is built into several activities: a) model interoperability is investigated, b) a data service is provided with web map service and web coverage service, c) data ingest is implemented with web coverage service. These aspects made it possible for broader adoption of the research results into other systems. This project made significant contributions to the interoperability capabilities of the foundation PHAiRS project through the development of enhanced OGC services. Specifically, the development and deployment of additional time-enabled WMS for DREAM-eta model outputs has facilitated the deployment of these Earth science products into public health decision support systems (SYRIS) while also demonstrating the value of developing standards-based delivery systems (i.e. KML) into other, more general visualization systems.

While the current project has identified limitations in the current generation of data delivery server software, it has also highlighted areas for further development in these applications, particularly in the areas of server and client support for the OGC standards. These lessons learned are outlined in the next section.

The interoperability concept utilized in this project aims to permit different modelling systems with different domains and resolutions to communicate in a general manner. This is achieved through the use of following approaches:

• a common pre-processor for both DREAM4-eta and NMM-dust; a corresponding decision was therefore made to use NMM with eta-like pre-processing.

• a common post-processor for both DREAM4-Eta and NMM-dust to provide

• common input formats for initial/boundary conditions for the higher resolution nested model members in the interoperability modelling chain

• common input for either GRADS or GRASS GIS post-processing and visualization

This required all initial/boundary conditions inputs prepared in the regular lat-lon grids at (10 in our setup) standard pressure levels for conventional and dust concentration data. As a common interface for these input parameters, the GRIB1 format was chosen to be the primary data format between models at all interface levels. Conventional GRIB encoder/decoder software programs were modified to be able to process dust parameters. The modification relates to the extension of the GRIB metadata information (i.e. extension of parameter tables that originally do not include aerosol data).

3.3 Future Research Topics

4. Publications


For All Inquiries: Research Building 1,4400 University Drive, Fairfax, Virginia 22030 Phone: 703-993-9341
Copyright © 2006-2013 George Mason University