The Bay Area, EPA data very consistent, in contrast to?
I was looking over all the EPA graphs here:
http://blog.alexanderhiggins.com/2011/04/12/realtime-epa-radnet-japan-nu...
If you look at San Francisco, the beta and gamma graphs are very consistent - very few blips or dips.
Now look at someplace like Sacramento or recently even Washington DC, or the gamma graph of Aurora IL - graphs where it looks like *something* blew through.
If the folks here at BRAWM are picking up measurable amounts of radiation in different things in the Bay Area, with the consistent low readings on the EPA beta and gamma graphs, doesn't it make you wonder what might be found in the areas that have more dramatic variation in their readings?
RadNet graphs show radon decay products
The local weather (especially rain, temperature, and pressure) can have very large effects on the concentration of radon gas and its decay products. Basically, higher temperatures and lower pressures cause radon gas to seep more quickly out of the ground. This phenomenon is what causes most of the spikes in the RadNet plots. You can tell because a lot of the spikes occur on a daily basis and correlate with temperature variations over the course of one day. This diurnal variation in radon concentration is well-known. (There are other features in the plots that are caused by various glitches, such as when filters are switched out, when no data is available, or if there is electrical noise.)
We in the San Francisco Bay Area are not particularly shielded from fallout in the atmosphere. We just have relatively cool, stable summer weather. Also, the levels of fallout seen throughout the world since March have been far too small to be seen in the RadNet graphs.
Mark [BRAWM Team Member]
Yes
yes, it does.