Half-hourly nowcast ap30 index

<?xml version="1.0" encoding="UTF-8"?>
<ComputationCapabilities xmlns="https://metadata.pithia.eu/schemas/2.2" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xlink="http://www.w3.org/1999/xlink" xsi:schemaLocation="https://metadata.pithia.eu/schemas/2.2 https://metadata.pithia.eu/schemas/2.2/pithia.xsd">
    <!--
The computation process that produces observed properties from its input data.
Input data may be an acquisition or some other computatation, not listed here yet.
Each newly computed observed property that this computation can produce is defined as its *capability*.
The list of capabilities is all-inclusive, even though not every computation can engage all capabilities.
    -->
    <identifier>
        <PITHIA_Identifier>
            <localID>ComputationCapabilities_Nowcast_ap30</localID>
            <namespace>gfz</namespace>
            <version>2</version>
            <creationDate>2023-05-30T10:00:00Z</creationDate>
            <lastModificationDate>2024-10-22T10:00:00Z</lastModificationDate>
        </PITHIA_Identifier>
    </identifier>
    <name>Half-hourly nowcast ap30 index</name>  
    <description>
        Half-hourly (30-minute ap-like) sub-auroral geomagnetic activity indicator provided by GFZ Potsdam, Germany. 
        The near real-time computation is based on 1-minute geomagnetic data from the contributing observatories.
        The quiet magnetic field is subtracted and the remaining disturbance is translated into H30 value.
        The H30 values are standardized at each observatory to obtain Hs30 values, from which Hp30 value is derived as a mean.
        The ap30 index is obtained as a linear scale representation of Hp30 according to a mapping table.
    </description>
    <capabilities>
        <processCapability>
            <name>Nowcast ap30 index, near-real time computationn</name>
            <observedProperty xlink:href="https://metadata.pithia.eu/ontology/2.2/observedProperty/MagneticField"/>
            <!-- Dimensionality: here we account for 4 platform constellation of Cluster -->
            <dimensionalityInstance xlink:href="https://metadata.pithia.eu/ontology/2.2/dimensionalityInstance/0D"/>
            <dimensionalityTimeline xlink:href="https://metadata.pithia.eu/ontology/2.2/dimensionalityTimeline/1DTimeseries"/>
            <cadence unit="hour">0.5</cadence>
        </processCapability>
    </capabilities>
    <dataLevel xlink:href="https://metadata.pithia.eu/ontology/2.2/dataLevel/L2"/>
    <type xlink:href="https://metadata.pithia.eu/ontology/2.2/computationType/ap30_index"/>
    <version/>
    <softwareReference/>
    <processingInput/>
    <algorithm/>
</ComputationCapabilities>