A Cray supercomputer arriving at the Observatory this week will be kept under 24-hour surveillance by closed-circuit camera and made available to only a handful of officers with security clearance.
Strict security was a condition of the export licence granted by the US Commerce Department, which approved the sale last month.
'It's all political. We need an export licence from the States because it's considered a hi-tech strategic commodity,' said Observatory senior scientific officer in weather forecasting Chan Chik-cheung.
The computer will be used to improve weather forecasting.
'Only a handful of people are allowed to use it - people who specialise in numerical weather prediction programming.
'It will be kept behind a glazed wall and monitored by closed-circuit TV 24 hours a day. When someone goes in, someone else would definitely know.' Mr Chan said it would be the first time a senior officer such as himself had been banned from using observatory equipment.