Model ETo (Evapotranspiration) with OCSM

[nikoskal]

The OpenAgri irrigation management https://github.com/openagri-eu/irrigation-management service provides calculations of the ETo for a specific location and for a specific time period.
This needs to be modeled with the use of OCSM.

[rapw3k]

hi @nikoskal is this related to this example?
https://github.com/openagri-eu/OCSM/blob/main/examples/evaporation.jsonld
This example provided by Jack looks good to me, just that we need to define still "Evaporation" class in OCSM.
Also as note, if we have multiple obsevation sharing some properties, e.g., featureOfInterest, observedProperty, time, madeBySensor, etc., then we could group them in an ObservationCollection to factorize those shared properties, like in https://github.com/openagri-eu/OCSM/blob/main/examples/pest-infestation-risk-v2.jsonld

let me know if this is sorted out or we need to add some terms.

[rapw3k]

hi @nikoskal
can you see if the example is what you need ?
after checking it again, i would change the observedProperty in the example to http://vocab.nerc.ac.uk/standard_name/water_evaporation_amount/ (see below)
please let me know if that is what you need, and ill fix example

{
        "@id": "urn:openagri:evaporation:calculation:72d9fb43-53f8-4ec8-a33c-fa931360259a",
        "@type": "Observation",
        "description": "Measurement or calculation of the evaporation of the soil on a parcel on a specific date",          
        "resultTime": "2020-10-22T00:00:00",
        "observedProperty": "http://vocab.nerc.ac.uk/standard_name/water_evaporation_amount/" ,
        "hasFeatureOfInterest": {
            "@id": "urn:openagri:soil:foi:72d9fb43-53f8-4ec8-a33c-fa931360259a",
            "@type": ["FeatureOfInterest", "Soil"]
        },
        "hasSimpleResult": "5.87"
    }

[nikoskalatzis]

Yes this is ok. What I am missing in this example is the units that are used to measure the "hasSimpleResult": "5.87".
Is it implied from the "http://vocab.nerc.ac.uk/standard_name/water_evaporation_amount/" that the Units are "Kilograms per square metre". Can we also include here the units so to make the life of developers easier?

[rapw3k]

hi @nikoskal
no, if yyou want to specify units (recommended) then you need to use hasResult instead of hasSimpleResult, like in other examples, i.e.,

{
        "@id": "urn:openagri:evaporation:calculation:72d9fb43-53f8-4ec8-a33c-fa931360259a",
        "@type": "Observation",
        "description": "Measurement or calculation of the evaporation of the soil on a parcel on a specific date",          
        "resultTime": "2020-10-22T00:00:00",
        "observedProperty": "http://vocab.nerc.ac.uk/standard_name/water_evaporation_amount/" ,
        "hasFeatureOfInterest": {
            "@id": "urn:openagri:soil:foi:72d9fb43-53f8-4ec8-a33c-fa931360259a",
            "@type": ["FeatureOfInterest", "Soil"]
        },
        "hasResult" : {
                    "@id": "urn:openagri:CompostMaterial:col1:obs2:result:94f652c1-b73a-454d-1234",
                    "@type": "QuantityValue",
                    "numericValue": 5.87,
                    "unit": "http://qudt.org/vocab/unit/KiloGM-PER-M2"
       }
   }

please confirm which one you use, and if needed we update example file