Quantitative Volcanic Ash Information Subscription and Request Service

The Quantitative Volcanic Ash Information Subscription and Request Service allows the service consumer to get quantitative volcanic ash information in accordance with ICAO Annex 3 Amdt 82 and PANS-MET.

The service consumer can subscribe to the service to receive notification when a new significant ash cloud occurs. It is also possible to send a direct request, using a request-reply mechanism, to the service to get the relevant quantitative volcanic ash information.

The meteorological information is issued by the designated Volcanic Ash Advisory Centre (VAAC). The meteorological information is only intended to be used by service consumers within the aviation domain.

The service shall offer quantitative volcanic ash information resulting from volcanic eruptions occurring in the service provider's area of responsibility, except when the responsibility of publishing this information has been transferred to another VAAC due to the ash cloud moving into the area of responsibility of this VAAC.

The service shall offer the equivalent quantitative volcanic ash information for the areas of responsibility for which the service provider acts as back-up during outages.

The service shall offer quantitative volcanic ash information resulting from volcanic eruptions occurring outside the service provider's area of responsibility, when the responsibility of publishing this information has been transferred by another VAAC due to an interruption of the operation.

Note: the back-up arrangements are based on mutual agreements between Volcanic Ash Advisory Centre service providers.

Note: the ash cloud may extend beyond the area of responsibility.

regulated information exchange

METEOROLOGICAL_INFORMATION_EXCHANGE

http://reference.swim.aero/information-services/service-categories/CodeRegulatedInformationExchangeType.html 

business activity

INFORMATION_MANAGEMENT

http://reference.swim.aero/information-services/service-categories/CodeBusinessActivityType.html 

intended service consumer

• CIVIL_AIRSPACE_USER
• MILITARY_AIRSPACE_USER
• CIVIL_AIR_NAVIGATION_SERVICE_PROVIDER
• MILITARY_AIR_NAVIGATION_SERVICE_PROVIDER
• NETWORK_MANAGER
• REGULATED_METEOROLOGICAL_SERVICE_PROVIDER
• AIRPORT_OPERATOR
• AIR_TRAFFIC_SERVICE_PROVIDER

https://reference.swim.aero/information-services/service-categories/CodeStakeholderType.html

REGULATED_METEOROLOGICAL_SERVICE_PROVIDER

• METEOROLOGICAL_FEATURE_ACCESS_SERVICE
• METEOROLOGICAL_INFORMATION_SUBSCRIPTION_SERVICE
• METEOROLOGICAL_COVERAGE_ACCESS_SERVICE

http://reference.swim.aero/information-services/service-categories/CodeServiceType.html 

The service consumer shall be able to request the latest quantitative volcanic ash information filtered by erupting volcano number, forecast timesteps and logical (e.g. severity threshold) operators.

Request the information in a specific format

The service consumer shall be able to subscribe in order to receive notifications when a significant volcanic ash cloud occurs and unsubscribe when needed.

There shall be a service policy to ensure that only service consumers within the aviation domain can use the service.

The service policy shall include a requirement that service consumers cannot pass the information obtained from the service to non-aviation users without prior authorisation from the service provider.

The service shall ensure consumer authentication in accordance with EUROCONTROL Specification for SWIM Technical Infrastructure (TI) Yellow Profile requirement SWIM-TIYP-0042.

The service shall ensure provider authentication in accordance with EUROCONTROL Specification for SWIM Technical Infrastructure (TI) Yellow Profile requirement SWIM-TIYP-0042.

The service shall ensure that satisfactory authorisation is put in place in accordance with EUROCONTROL Specification for SWIM Technical Infrastructure (TI) Yellow Profile requirement SWIM-TIYP-0070.

The service shall achieve a quality that is sufficient to ensure the service is fit for purpose.

The service should ensure that a single user is unable to monopolise a service or to degrade it below agreed service levels for others users.

The service shall achieve a quality that is sufficient to ensure the service is fit for purpose.

Note: the following factors must be used in deciding the fitness for purpose:

• the availability offered by the designated back-up VAACs
  
• the number of users likely to be delayed significantly by a loss of the service
• the acknowledgement that the availability is expected to be higher when a volcano is erupting

The service shall ensure confidentiality by using SWIM Technical Infrastructure (TI) Yellow Profile bindings.

The quality of quantitative volcanic ash information offered by the service shall be verified by the service provider.

Information on the quality of the QVA information offered by the service shall be reported annually to the ICAO Met Panel Met Operations working group relating to the IAVW who provide oversight of QVA data provision

The service provider shall ensure that the quantitative volcanic ash information offered by the service is based on data received from the appropriate authorised originating sources. This includes:

• Volcano observatory
• REGULATED_METEOROLOGICAL_SERVICE_PROVIDER acting as a designated VAAC.

Note: EUMETSAT may be used to make sure the ash plume corresponds to where it is already being detected by the satellites.

• PUBLISH_SUBSCRIBE
• SYNCHRONOUS_REQUEST_REPLY

Quantitative Volcanic Ash Information Subscription and Request Service Request Interface

Allows the service consumer to subscribe to the service. It allows the service consumer to manage the subscriptions e.g. to unsubscribe.

Note: this can be handled by a separate dedicated subscription service.

Note: some service providers will prefer to receive subscription requests by email.

GetFeature

Request, Quantitative Volcanic Ash Information Message

Meteorological SWIM Services Subscription Interface Standard

The standard operations for subscription and subscription management.

The following operations shall be implement at a minimum:

• subscribe
• unsubscribe

publish

This operation allows the service provider to publish Quantitative Volcanic Ash Information Notifications to service consumers based on their subscriptions.

Quantitative Volcanic Ash Information Notification

Quantitative Volcanic Ash Information Message

The output message containing the quantitative volcanic ash information.

QVA information shall be provided in two file formats:

• ICAO’s Meteorological Information Exchange Model (IWXXM) format containing a collection of features;
• NetCDF file containing gridded volcanic ash concentration data.

Note: the file may be compressed.

Request message submitted to the service containing query expressions for the WFS GetFeature operation, WCS GetCoverage operation or the EDR HTTP GET operation and the required data format for the Quantitative Volcanic Ash Information Message.

Quantitative Volcanic Ash Information Notification

The notification and way to retrieve the Quantitative Volcanic Ash Information Message e.g. the URL, or the volcano number.

The message will include:

• publication time
• operation e.g. if it is an update or a new message

The message can include:

• identifier of the VAAC
• event type e.g. if it is live

Note: an example of the structure of the URL that is used to retrieve the QVA in IWXXM format using an EDR implementation: https://{organizaton URL}/QVACI_Iwxxm/Locations/{VolcanoNumber}

Note: the URL, if provided, could be a request formatted for the Quantitative Volcanic Ash Information Subscription and Request Service Request Interface.

JSON and/or XML

The IWXXM QVA information shall include feature information for four ash concentration thresholds (≥0.2mg/m3, ≥2.0mg/m3, ≥5.0mg/m3, ≥10mg/m3) in accordance with the QVA IWXXM schema.

The probabilistic QVA information shall include the probability of exceeding four ash concentration thresholds (≥0.2mg/m3, ≥2.0mg/m3, ≥5.0mg/m3, ≥10mg/m3) at a 0.25 degree horizontal resolution and for 12 vertical levels in accordance with the NetCDF4 specification for gridded data.

The deterministic QVA information shall include an expected ash concentration for each grid point at a 0.25 degree horizontal resolution and for 12 vertical levels in accordance with the NetCDF4 specification for gridded data.

All information types shall be provided for the period 0-hours to 24-hours at 3-hourly intervals.

Note: the QVA IWXXM schema is expected to be included in the 2025-2 IWXXM release.

The Quantitative Volcanic Ash Information Subscription and Request Service Request Interface shall support filtering by volcano number (i.e., the IAVCIE number) and forecast timestep (dateTime).

The Quantitative Volcanic Ash Information Subscription and Request Service Request Interface should support filtering of probabilistic information based on the ash concentration threshold (≥0.2mg/m3, ≥2.0mg/m3, ≥5.0mg/m3, ≥10mg/m3).

The Quantitative Volcanic Ash Information Subscription and Request Service Request Interface may support filtering based on geographic bounding box defined in the OGC Filter Encoding 2.0 Encoding Standard.

The Quantitative Volcanic Ash Information Subscription and Request Service Request Interface shall support the selection of one or more of the supported data set types.

If the service implements the OGC API – Environmental Data Retrieval Standard, the Quantitative Volcanic Ash Information Subscription and Request Service Subscription Interface shall allow for the selection of subscription based on clearly defined criteria.

Note: for example, subscriptions can be for all QVA messages or by volcano number or by data format type (deterministic, probabilistic or in IWXXM format).

Uniform Resource Locator

• https://www.ogc.org/standard/ogcapi-edr/
• https://docs.ogc.org/is/19-086r6/19-086r6.html 

WFS offers direct fine-grained access to geographic information at the feature and feature property level. 

Note: This is equivalent to ISO 19142 - Geographic Information - Web Feature Service.

This jointly developed OGC and ISO TC/211 International Standard describes an XML and KVP encoding of a system neutral syntax for expressing projections, selection and sorting clauses collectively called a query expression. These components are modular and intended to be used together or individually by other standards which reference this International Standard.

Note: This is equivalent to ISO 19143 - Geographic Information - Filter encoding.