**5. Applications exploiting e-infrastructures**

In the course of the last five years a specific effort was dedicated to the support of several user communities including Biology, High Energy Physics, Material Science, and Earth & Atmospheric Sciences.

For each user community specific applications were deployed on the grid infrastructure and each application was supported by a collaboration of European and Indian partners. Scientific and technical results were presented at relevant international conferences or published on journals and represent a clear measure of success of the user communities' activity.

A short guideline on how to enable applications on Grid infrastructure has been also drawn up by the EU-IndiaGrid projects based on the experience collected within various user communities. The document had the goal to offer a first support to users interested in using the EU-IndiaGrid infrastructure to its best. In such a document we propose that a successful procedure for Grid-enabling application should be performed in the following five major steps:


At the end of each intermediate step an evaluation procedure takes place to understand if the action should move to the next step, should be stopped with the execution of the final step, or should go back and repeat the step previously done. It is worth to note that such procedure was elaborated keeping in mind the point of view of the users: this is why we

Applications Exploiting e-Infrastructures Across

**5.1.1 RegCM 4.1.1 exploitation on the GRID** 

was then released in June 2011.

grid of the chosen domain.

simulation down dramatically.

be investigated thoroughly in the future.

**5.1.1.1 RegCM on gLite** 

processor:

properly.

Europe and India Within the EU-IndiaGrid Project 297

In the following subsection we will discuss the porting strategy of the package toward the

RegCM4 is the fourth generation of the regional climate models originally developed at the National Centre for Atmospheric Research (NCAR) and currently being developed at ICTP, Trieste, Italy. It was released in June 2010 as a prototype version RegCM4.0 and as a complete version RegCM4.1 in May 2011 (Giorgi 2011). A bug fixing release RegCM4.1.1

The RegCM4.1 package now uses dynamic memory allocation in all its components. The whole output subsystem is now able to produce NetCDF format files, which is in better

The RegCM modelling system has four components namely Terrain,sst,ICBC, RegCM and some postprocessing utilities. Terrain sst and ICBC are the three components of RegCM pre-

Th first step will define the domain of the simulation: the executable terrain horizontally interpolates the landuse and elevation data from a latitude-longitude grid to the cartesian

Sst executable then creates the Sea Surface Temperature file. Finally the ICBC program interpolates Sea Surface Temperature (SST) and global re-analysis data to the model grid.

The pre-processing phase will therefore need to read global re-analysis data (size of the order of several dozen GB for each year of simulation) and will produce a large size of input

As an example, a monthly run on domain of 160x192 points will produce around 10 GBytes of data, which means around 10 TBytes of data are produced for a climate simulation lasting a century. This data needs to be locally available, as a remote file system would slow the

The greatest challenge in running RegCM on the GRID is therefore handling the data

The present day status of the RegCM software and the GRID gLite infrastructure makes it not really suitable for long production runs, which require a number of CPUs in the 64-256 range, but a well implemented MPI handling mechanism, such as MPI-Start, makes the running of small to medium size RegCM simulations feasible. The data transfer from and to the GRID Storage Elements is still a matter of concern and its impact on performance should

The GRID could be therefore used with proficiency for physical and technical testing of the code by developers and users, as well as for "parametric" simulations, that is. running many

shorter/smaller simulation with different parameterisation at the same time.

These files are used for the initial and boundary conditions during the simulation.

data as well. RegCM itself produces than a large amount of output data.

Euro –Indian infrastructures and the innovative solution we developed.

compliance with the standard Climate and Forecast Conventions.

insist that the procedure should have in any case (even if it is stopped after the initial step) a final dissemination phase. The results (even negative) can be of great importance for other users as initial input when starting the Grid-enabling procedure. Several successful porting stories followed this approach as reported in the EU-IndiaGrid deliverables dedicated to applications and in other publication as well, see e.g. a few papers in (Cozzini, 2009).

In the following subsection we report two successful and outstanding examples of scientific application within the project, which exploited at best the euro-Indian infrastructure in a joint collaboration among Indian and European partners.
