Nuclear aurora

[Blind groper]

Fifty years ago, this month, when I was a callow lad of just 13, I was with my family at night, and we saw the whole sky light up like an aurora. Since, in those days, I did not follow the news, I had no idea what was going on. My father did, though, and he told me "it was those bloody Americans with their atom bomb."

In fact, the 'aurora' was the result of high altitude testing of a hydrogen bomb. July 9 1962, the United States fired the device to 400 kms (250 miles) above Johnston Atoll in the North Pacific and detonated it.

This stimulated paranoia here in New Zealand. Lots of people became convinced that the radiation spreading from the bomb testing would cause widespread cancers, and would be a disaster. It was not till many years later, when I was at university, that I saw a credible opinion to the contrary. I was given an article to read which actually quoted numbers, rather than vague opinions. I learned that the addition to background radiation from the bomb testing was almost unmeasurable due it being so small. Normal background radiation was much greater.

Today, I am much more skeptical about issues, unless I see the actual data. Vague opinions cause incredible fear and anxiety, where a few solid numbers can assuage the concern. Why are people so averse to numerical data, and so willing to believe the worst of situations, when no solid data is available?

[Azathoth]

[Rum]

I think it was an understandable reaction to be fearful and paranoid. After all the two most powerful countries on the planet were racing to make bigger and nastier weapons than each other and had long since developed the capacity to wipe out human civilization from the planet and possibly sterilize it altogether. This was all done in secrecy for the most part, with tests going on in some of the remotest and/or most beautiful parts of the world. All in a background of sabre rattling and proxy wars any of which could have flared up into WW3.

It was terrifying, as I remember all too well. The day the Cuban Missile Crisis came to a head and we almost did it to ourselves is one I shall never forget and I was only 11 or so at the time.

[Blind groper]

I am more concerned here with the fallacies surrounding nuclear radiation.

Obviously, if you get hit with a large dose, you die. However, lots of people think that small doses are also a terrible curse. This is simply not true.

Every human is subject to the background level of radiation. Our bodies have evolved resistance over millions of years. We receive an average of about 2.5 millisieverts per year, but there are some places on Earth where the background level can run up to 250 millisieverts per year, and the residents appear to be totally unharmed. No higher rates of cancer, even. Follow up research over decades on Hiroshima survivors also show that those who received 100 millisieverts or less in one whack have levels of long term cancer (or other health problems) no worse than the average anywhere else in Japan.

There is even some evidence that higher radiation doses (within the above limits) may stimulate the DNA repair mechanisms of the body, and thus make us less, not more, vulnerable to cancers.

The situation is made to look worse by the fact that legal exposure limits are very, very conservative. For example 1 millisievert per year as a dose for the general public is common to many countries. Since the public already receive 2.5 and possibly up to 250 millisieverts per year from 'natural' radioactivity, without harm, this seems terribly conservative.

The whole situation appears to me to be geared to paranoia and emotional logic. Good scientific sense is largely absent.

[macdoc]

This is a very useful chart to put things in perspective
http://www.ritholtz.com/blog/2011/03/ra ... e-chart-2/

[Blind groper]

To macdoc

Thanks for that. I have seen that chart before and based some of my numbers on it, but it is well worth posting, and I hope some of the people here will take a close look.

When you look at hard data like that, you can see how much of what ordinary people believe to be true is just garbage.

[macdoc]

Now we just need to get you up to speed on AGW

[Blind groper]

Now, now, macdoc.
Our little dispute was not over AGW, which I suspect both of us are fairly knowledgeable about. It was about northern agriculture.