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In this quarter we successfully deployed Polytope for the FDB that holds COSMO/ICON data at MeteoSwiss. The design considers a cross-platform deployment between CSCS (that host FDB) and AWS in order to leverage the use of AWS managed services. 
The design is shown in the figure below. A similar design will be deployed for the ECMWF production, in order to serve IFS production data to the use cases of the pilot project running in EWC. 

Gribjump Server

The gribjump server (part of FDB/polytope) allows to serve data for only grid points or regions, instead of entire hypercubes. As part of the FDB ecosystem of servers, polytope will accepts requests to grid point data, timeseries, trajectories, etc. that might look the following example for a timeseries extraction. 

"request": {
        "class": "od",
        "stream": "enfo",
        "type": "ememb",
        "levtype": "sfc",
        "date": "20240222",
        "time": "0300",
        "expver": "0001",
        "model": "ICON-CH1-EPS",
        "param": "500011",
        "number": "1",
        "feature": {
            "type": "timeseries",
            "points": [
                [
                    47.45268,
                    8.56523
                ]
            ],
            "start": 0,
            "end": 300
        }
    },
    "verb": "retrieve"

This functionality of polytope will be crucial since typically more than 50% of the requests of model data are a small selection, around a region, station or trajectory. This functionality then allows to efficiently extract this data from FDB without having to transfer entire hypercubes to the client. 

The development of the grib jump is in an early state, however we could successfully prototype and test it for the COSMO/ICON data accessing a single grid point. At the moment it supports only geographical (global and regional) lat lon coordinates. 

Future developments will extend it to other grids, like rotated lat-lon, or unstructured meshes like the ICON grid. We will profile and benchmark this type of data accesses in the following months.