Progress report on the Snowy Mountains cloud seeding trial (Apr 09)
Pluviometer with a wind shield in the Snowy Mountains |
| What is cloud seeding? |
|
Cloud seeding is a form of weather modification. It involves deliberate introduction of various substances, such as silver iodide and solid carbon dioxide (dry ice)
|
into clouds to induce precipitation that falls as rain or snow. Cloud seeding has been done from aircrafts, rockets, cannons and ground generators.
|
Snowy Hydro Limited (Snowy Hydro) is conducting a cloud seeding trial in the Snowy Mountains to understand whether cloud seeding can successfully increase snowfall in this area. The trial is authorised under the Snowy Mountains Cloud Seeding Trial Act 2004 (the Act), subject to certain conditions.
The NRC is responsible under the Act for supervising Snowy Hydro’s cloud seeding operations during the trial period and for reporting on the environmental impact of those operations.
The Act was amended in 2008 to extend the duration of trial and area of the trial. The duration of the trial was increased by an additional five years (taking the total trial period to 11 years). The target area was expanded by more than 1000 square km (taking the total area to around 2000 square km). To reflect these changes, Snowy Hydro made revisions to its Environmental Management Plan for the trial.
In March every year, Snowy Hydro provides an annual report to the Ministers on the cloud seeding operations of the previous year.
| NRC's advice to Government |
The NRC provided a progress report (Apr 09) to Government by evaluating Snowy Hydro’s environmental reporting, as contained within its 2007 and 2008 annual reports. The NRC also visited cloud seeding sites in the Snowy Mountains and consulted with Snowy Hydro and a number of affected stakeholders.
The NRC found that:
- Snowy Hydro has developed an innovative technology for ground-based cloud seeding operations and continues to employ the best available meteorological science to select clouds for seeding.
- Snowy Hydro is conducting the trial in compliance with the Act and has made progress in most areas previously identified by the NRC for improvement
- though there was no evidence that the trial has had a significant environmental impact to date from the aspects that are monitored and reported annually, the NRC has recommended that Snowy Hydro strengthen and review some aspects of the trial (see progress report for details).
Below are the NRC's reports from previous years.
Progress report on the Snowy Mountains cloud seeding trial (Jun 07)
Review of Snowy Precipitation Enhancement Research Project Annual Report 2004 (Oct 05)