We should actually consider two different TRLs:
- the hardware (i.e. the monitoring units which will be deployed on the field) is at TRL 9, since the same GNSS units have been used by large clients of GReD for critical infrastructure (i.e. bridges, dams, high-voltage towers) and land (i.e. landslides) displacement monitoring for more than 1 year.
- the overall water vapour monitoring system, which includes innovative (server-side) components such as the local ionospheric delay modelling and the continuous estimation of tropospheric delays, from which the integrated amount of precipitable water vapour can be inferred. This is more likely at TRL 6, since the technology has been demonstrated in relevant environment, namely by dedicated dense networks deployed for testing; however, it was not demonstrated in an actual operational environment, where water vapor data would have to be analysed for probabilistic nowcasting in order to issue timely early warnings.