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GCW Station Application Process

GCW welcomes the contribution of any station that makes measurements of the cryosphere. Its goal is to design a network that advances WMO’s scientific and operational objectives. The process of evaluating a station or a site for inclusion in the GCW surface network is described below. It is the same for stations and sites, core (CryoNet) and contributing, unless indicated otherwise.

  1. A representative of the station or site (hereafter, the “applicant” and the “station”) completes and submits the station questionnaire (the “application”) on the GCW website (globalcryospherewatch.org/cryonet/questionnaire).
    • It is recommended, though not required, that the applicant present the station at a GCW meeting before beginning the application process.
    • By submitting the application for a core station, the applicant is implicitly agreeing that the station meets the CryoNet Minimum Requirements. A commitment to longevity, data quality, and data distribution is particularly important.
  2. In addition to the online questionnaire, a letter of endorsement is required before the station/site receives final approval. It is recommended that it be provided as early as possible in the process. For all proposed stations, either operated by the WMO Member’s national meteorological or hydrological service (NMHS) or another entity, the WMO Permanent Representative (PR) of the station’s operating country must provide a letter of endorsement to WMO. (Click here for a template. PR information can be found at https://www.wmo.int/cpdb/.) For stations that are located in a country other than that of the proposing organization, the agreement to operate in that country and to share data as per GCW requirements must be provided. The PR of the country in which the station is located must be informed that the station could become part of CryoNet. For stations operating in Antarctica, the stations should be endorsed by the PR of the country of the proposing organization. For mobile platforms operating in international waters, or by an international consortium, endorsement is done by the designated PR of the concerned countries with concurrence by the chair of the relevant consortium.
  3. The application is examined by the WMO Secretariat for completeness.
  4. The GCW CryoNet Team, in consultation with relevant experts, evaluates the application1. This is normally done annually, but may be expedited in some situations. There are no site visits.
  5. If the Team recommends that the station not be included in the GCW surface network, feedback is provided to the applicant. The application can be modified and resubmitted at any time.
  6. If the Team recommends that the station be included in the network, the GCW Steering Group (GSG) makes its determination. This is normally done at GSG annual meetings. If the GSG recommends that the station not be included in the GCW surface network, feedback is provided to the applicant.
  7. If GSG recommends the station for inclusion in the network, the station is conditionally accepted and enters a one-year trial period. The station shall operate according to the Minimum Requirements, including the submission of data and metadata.
  8. GSG informs the EC-PHORS at EC-PHORS regular meetings, regarding the selection of stations for the CryoNet network. EC-PHORS meets every 12-15 months.
  9. EC-PHORS, upon recommendation from GSG, approves and submits the list of selected stations for approval by the WMO Executive Council (EC). EC meets annually.
  10. The approval process following the GSG decision takes place in parallel with the one-year trial period.

Each CryoNet station will be evaluated annually to ensure that it continues to meet the Minimum Requirements. If it does not, a timeline for correcting deficiencies will be mutually agreed upon by the Team and the station representatives. If no agreement can be reached, the station will be removed from the CryoNet network or, by mutual agreement, will become a contributing station.

A change in the station type, core or contributing, requires reapplication. This entails a modification to the original application, resubmission, and re-evaluation by the Team and GSG. It does not require approval by EC.

Stations may be withdrawn at any time from the GCW surface network by request, in writing, of the station owners/operators.

When an application is submitted via the online questionnaire process, the station is listed on the GCW website as “candidate”. It is not yet part of the GCW surface network. When the GCW Steering Group recommends stations for inclusion in the surface network, for all practical purposes they are part of the GCW network and will be listed on the website accordingly. They are not, however, officially part of the network until approved by EC.


1To ensure a unique, high-quality network of surface observations, stations and sites are evaluated for inclusion in CryoNet based on several factors. Fulfilling the minimum requirements does not in itself guarantee acceptance as a CryoNet station. Other criteria that are considered by the CryoNet Team when evaluating applications include (1) the number of recommended variables that are measured (see the lists), (2) the continuity and length of the data record, (3) the extent to which data are available and accessible, (4) sustainability of the station, (5) conformity to GCW best practices, and (6) the location and representativeness of the proposed station relative to the geographic distribution of existing CryoNet stations.