Integrated Grid workflow for mesoscale weather modeling and visualization Zhizhin, M., A. Polyakov, D. Medvedev, A. Poyda, S. Berezin Space Research Institute of the Russian Academy of Sciences

Abstract For the model input and output we use a scalable parallel storage and data mining system called ActiveStorage. It can store different types of weather data, provided they are in the same Command Data Model (UNIDATA CDM): NCEP reanalysis, NCDC stations weather data, MM5 model output. The MM5 is a mesoscale weather forecast model. For the input boundary conditions the model takes basic parameters such as elevation, air pressure and temperature, etc. It can ingest reanalysis and direct observation data. As the output the model provides high-resolution regional weather grids. To make the MM5 input data and the modeling results accessible on the Grid to the Earth Science community, we have developed a set of grid services (resources and activities) inside the OGSA-DAI (both ver. 2 and 3) grid service container. To visualize the weather data we have developed a special plugin for the NASA World Wind which can read the data directly from the OGSA-DAI resources and plot it over the 3D globe in different ways, such as contour lines, filled areas and vector fields.

Active Storage, Modeling, Data Mining and Visualization Services

ActiveStorage ActiveStorage is a generic storage for arrays of primitive data types. Its data model is based on the Unidata’s Common Data Model, used in netCDF, HDF5 and OpenDAP. Basically, ActiveStorage is a SQL Server database with CLR stored procedures and a client library. The stored procedures and the client library provide an abstraction layer for data access. Large arrays are split into chunks and can be spread across several parallel database servers for better performance.

SQL Server 2005/2008 DB ActiveStorage components Metadata tables Data and directory tables Stored procedures Client library

Common Data Model This is the Common Data Model (CDM) used in the recent versions of OpenDAP, netCDF and HDF5. Its purpose is the representation of multidimensional scientific data.

How it works SQL Server DB Client library 2. Issue commands to the database server 3. Select the requested data from several chunks 3. Return the data parts to the client library 4. Assemble the data parts into one multi-dimensional array 1. Pass multi-dimensional data request to the client library Application

Parallel query processing SQL Server DB 1 Client library Application SQL Server DB 2

Parallel query performance 1 database server 4 parallel database servers

NCEP/NCAR Weather Reanalysis Continually updating gridded data set Incorporates observations and global climate model output 74 weather parameters 5000 netCDF files, 30 – 500 MB each Time coverage: 1948 – hourly values Grids: Regular grid, 2.5 x 2.5 degrees T62 Gaussian grid, 192 x 94 points.

NCDC Integrated Surface Database 1901 – 2008 time coverage. 30 million sensors. 1.7 billion observations. Fixed ground stationsShipsMobile stationsBuoys FM V N N N ADDGA KA1120N datetimelatlon Mandatory data sectionAdditional data sectionSection marker Group marker Parameter group Control data section ASCII files packed with gzip. 50 GB packed; 400 GB unpacked. When you’ve downloaded and unpacked the data...

import ru.wdcb.mdb.NcConnector import com.microsoft.sqlserver.jdbc.SQLServerDriver s = 'jdbc:sqlserver://localhost:1433;databaseName=NCEP_01;user=g uest;password=guest'; connector = NcConnector(); ncid = connector.nc_open(s,0); varid = connector.nc_inq_varid(ncid,'air'); origin = [ ]; size = [ ]; stride = [ ]; A = connector.nc_get_vars_short(ncid,varid,origin,size,stride); plot(A, 'DisplayName', 'A', 'YDataSource', 'A'); figure origin = [ ]; size = [ ]; stride = [ ]; B = connector.nc_get_vars_shortm(ncid,varid,origin,size,stride); B = reshape(B,[73 144]); imagesc (B); figure(gcf); MATLAB script using ActiveStorage library

Environmental Data Service: OGSA-DAI plugin

Activities for data export XML output stream – We have plugin for NASA World Wind to visualize XML- formatted data – Can easily be transformed using XSLT to web page or another XML document, e.g. MS Excel – Can be used as input for ESSE fuzzy logic search engine NetCDF binary data file – Standard for scientific data storage in files – There are several visualization programs for NetCDF – Compatible with Unidata Common Data Model standard

Data flow management by OGSA-DAI OGSA-DAI query from single data source OGSA-DAI query from distributed data sources

Parallel mesoscale weather model MM5 Same Source Parallel MM5 Source code for the parallel MPI and the single process MM5 model are the same Automated parallel code generation from MM5 sources by ANL: –FLIC compiler –RSL library for model domain segmentation and message exchange We have ported MM5 code to the MS Windows Server 2008 HPC platform

MM5 model as a grid client

Visualizing data from ActiveStorage with NASA WorldWind A NASA WorldWind plugin, developed at the Moscow State University allows to retrieve data from ActiveStorage via an OGSA-DAI service. Several kinds of visualization are available: - isolines - color map - vector field OGSA-DAI services can be used by other applications to retrieve data from ActiveStorage

NASA World Wind as a grid client Using OGSA-DAI services and a special API plugin, the NASA World Wind can visualize both the MM5 input and output datasets