Intervals

[SiBell]

So many of us will be dealing with observations that apply to a time interval rather than a single instance in time. It's worth confirming how we handle these.

An example would be precipitation accumulation from a rain gauge. It's not enough to say 3 mm of rain was recorded at 10:40 pm, we need to know whether that 3 mm was collected over the last minute, or hour, or day, etc...

The Time Ontology makes the distinction between a Time Instant and a Time Interval.

This article also has some nice meteorological examples showing which observedProperty's would be instant and which would be interval.

This SSN Example also makes use of a Time Interval. Using this as a basis, an observation of precipitation accumulation could therefore be structured as:

{ 
  "madeBySensor": "rain-gauge-no-3",
  "observedProperty": "precipitation-accumulation",
  "resultTime": "2020-02-12T11:30:00.000Z",
  "phenomenonTime": {
    "hasBeginning": "2020-02-12T11:00:00.000Z"
    "hasEnd": "2020-02-12T11:30:00.000Z"
  },
  "hasResult": {
    "value": 3
  }
}

N.b. I haven't made this example JSON-LD compliant, but I should have.

[lukeshope]

Just to say, I agree with this proposal. It appears in one of the SSN examples too.