I just discovered that my gamma detector here in Oslo, Norway spiked wildly today to more than 10 times the normal background radiation. It looks like a sensor problem, but is there any gamma detectors online? I vaguely recall something in Finland, but I'm unable to find it.
You are referring to the Oulu cosmic ray station: cosmicrays.oulu.fi/ But it only detects neutrons generated by "cosmic rays" (which are actually highly energetic particles) which collide with the detector.
Yes, it was Oulu I had in mind, but the other links were useful, too, if not more useful. My readings spiked again last evening. The detector is in a room with no heating, and I suspect that the problem occurs when the room temperature drops below -10C. Perhaps the battery becomes too weak in the cold. At least it seems more likely than that there have been nuclear accidents two nights in a row nearby.