Navigators—your clocks are running. You have about five years to get your sextant skills up to scratch.

According to a report in New Scientist, recent research has indicated that navigation, power and communications systems that rely on GPS satellite navigation will be disrupted by violent solar activity in 2011.

Solar activity operates in 11-year cycles, culminating in an extreme period known as the Solar Maximum. Charged particles from solar flares produce intense bursts of radio noise, which peak in the 1.2 and 1.6 gigahertz bands used by GPS. Normally, radio noise in these bands is very low, so receivers can easily pick up weak signals from orbiting satellites.

The problem has been undetected until now because the GPS system we have come to rely upon has been generally widespread since only the late 1990s, during a period of low solar activity. When the solar cycle reaches its peak, intense solar flare radio bursts could cause signals to drop by up to 90%, for hours at a time.

Perhaps it's time to break out the star charts and rehearse dead-reckoning skills before you find yourselves adrift in a sea of troubles.