To be eligible to participate to G-VAP, a candidate data record should fulfill the following requirements:

• Comprise at least one of the G-VAP core parameters: TCWV, UTH, WVP.
• Cover a time period of at least ten years.
• Be based on a mature algorithm; that is, no updates shall be planned before the end of the data record upload period in autumn 2014.
• Be well documented and freely available.
• Be supported by an expert throughout the assessment period.