The Ministry of Defence has put out warnings about two periods when Global Positioning System signals will be jammed.

However, these shouldn’t trouble most outdoor users – the signal interruptions will take place at sea. So unless you’re a very strong paddler or brave enough to paraglide out over the water, it’s unlikely you’ll be troubled.

GPS: land signals not affected 

Just so you know, GPS signals will be subject to defence jamming exercises during two periods: 31 March to 4 April and 20 to 21 April.

During the former, GPS readings east of Bridlington in North Yorkshire will be affected. The exact co-ordinates are: N54° 06.842’ W000° 05.045’. This is about 15km (9 miles) out to sea. The latter will take place in the sea around the Hebrides at N57° 14.4’ W007° 26.7’. By our reckoning, that’s midway between Barra and Rum. Definitely wet territory.

Sailors and flyers beware. The rest of us should still be able to use our little receivers with accuracy.

The notifications come from Ofcom, the agency which governs radio broadcasting in the UK, and are supplied to it by the MoD.