The mass of fine particle now circulating the globe as a result of the Volcanic eruption in Iceland have been blamed for GPS systems such as Satellite navigation units in cars and navigational aids in aircraft becoming slow to acquire a signal and in some cases absolutely useless.
This is due to the fine particles of volcanic ash reflecting the signals from the satellites orbiting the earth and blocking their transmission of data to the units on the ground.
Andre Ward of the Institute of Geological Information and Technology Solution service (UK) said "People may observe a longer duration awaiting satellite lock when they boot their Sat Nav's, and some may find that their systems are unable to locate a satellite fix at all. My own system which I have in my car which normally takes 60-90 seconds to gain satellite lock is now taking up to 5 mins to acheive this".
The grounding of aircraft around the world due to the presence of the volcanic ash in the atmosphere is due to worries about the effect of it's ingestion into jet engines, damage to wing leading edges and aerodynamic surfaces and also it's effect on increasingly sophisticated navigational aids.
The particles of volcanic ash are expected to disperse over a few weeks, but in the meantime people are being urged to rely less upon GPS navigation systems and be prepared for possible interruptions in the facility.