Sunspots.........Evan

[ahidley]

Hello Evan, I saw in your other post that you mentioned sunspots starting. A few months ago was the lul in sun spot activity. So a question for thoes who know.. What will sun spot activity do in the next 7 years as it progressivly gets worse to our now transistorized life style, i.e. cell phones, wireless laptops, VFDs, DROs, etc?

[Todd Tolhurst]

The last solar maximum was in 2001, at which time we were pretty well transistorized, with cellphones, wireless laptops. VFDs, DROs, etc. Do you remember all the havoc that caused?

Me neither.

This is not to say that exceptional solar activity doesn't have negative effects on the Earth and our technological infrastructure. Coronal mass ejections can be bad news for satellites and electrical power transmission systems.

As an amateur radio operator, I welcome the rising sunspot numbers, as it means better conditions for long-distance radio communication. It's been a long dry solar minimum.

[Evan]

There are a number of effects that can be caused by solar events as a result of sunspot activity. As Todd mentioned the geomagnetic field can be disrupted which will induce currents in long power transmission lines and can cause them to fail. That happened in 1989 when an X class geomagnetic storm took the entire Quebec power grid off line and nearly killed the earstern half portion of the US grid too.

Other side effects are an increase in radiation levels in the vicinity of the earth. They can be strong enough to be hazardous to astronauts and in extreme events even possibly lethal. Satellite solar arrays can be permanently damaged. Satellites in low earth orbit including the Space Station have have their orbits severely disrupted as the atmosphere balloons outward because of the extra energy dumped into it. That was the reason that SkyLab reentered before anything could be done to save it.

Radiation levels can go high enough that "ground level events" may occur. The ground level background count may double although that isn't significant. What is significant is that crew on international flights could be exposed to an entire year's maximum radiation dose in a single flight. This would mean that they would be grounded for the next 12 months.

There is also a connection between climate and sunspots. High sunspot counts are correlated with more extreme weather including hotter summers and colder winters with an overall increase in average temperatures.

[dp]

There's another fascinating study that shows correlation between solar activity and river flow:

http://wattsupwiththat.com/2010/07/22/solar-to-river-flow-and-lake-level-correlations/

When the solar minimum coincides with a La Nina ocean shift it's quite bad - as we see in recent South American weather. It's been so cold penguins are dropping dead.

[Hollowbuilt]

What about the passengers?

Radiation levels can go high enough that "ground level events" may occur. The ground level background count may double although that isn't significant. What is significant is that crew on international flights could be exposed to an entire year's maximum radiation dose in a single flight. This would mean that they would be grounded for the next 12 months.

Evan, what about the passengers on this intl. flight? What risks are they taking?
Chris

[Evan]

No risk at all. The maximum dose they are likely to receive is about the same as a chest x-ray which is a very low dose. The international standards for radiation exposure for workers that are exposed to ionizing radiation are extremely strict. Most countries including the US and Canada subscribe to those standards.

To give some perspective the CT scan I had recently delivered the equivalent radiation of 500 to 1000 chest x-rays.

[macona]

There was an article in New Scientist about radiation dosage:

http://www.newscientist.com/article/mg20727715.800-whos-afraid-of-radiation.html

But, its an old article now and you have to pay to access it. But the gist of the article is ionizing radiation maximum dosage limits are extremely over cautious. There is a lot of hype about radiation dosage which does more harm than good.

[Fasttrack]

Actually the NRC is quite strict about the limits the public is allowed to recieve, as well. However, they define dose as radiation recieved above background. Background includes medical x-rays, cosmic sources, etc.

The NRC requires that the public recieve no more than 100 mrem per year above background. Employees are not allowed to recieve more than 5000 mrem per year. Most employers have their own limits well below the federal limit. For instance, at Fermi National Accelerator Lab, I'm only allowed to recieve 1000 mrem per year and I have to get permission from the RSO if I expect to accumulate more than 50 mrem on any given day.


Solar activity also lights up super-K like a Christmas tree and can produce a lot of noise in neutrino oscillation experiments like Minos and Minerva.

[rollin45]

Apparently there was a dandy of a solar storm in 1859, caused quite a lot of damage then, if a similar one were to happen now, there is no telling the extent.

http://www.space.com/scienceastronomy/mystery_monday_031027.html

rollin'

[GadgetBuilder]

The current sunspot cycle is not starting up as originally predicted. NOAA has revised their predictions downward several times, the current prediction is here:

http://www.swpc.noaa.gov/SolarCycle/

and the cycle is again below their prediction. Cycle 24 will likely be the lowest in a while, well below the mean:

http://en.wikipedia.org/wiki/List_of_solar_cycles

John

[Evan]

The CT scan I recently had delivered a whole body equivalent of a little over 1 REM. But, because it wasn't a whole body dose the maximum delivered to the local area if delivered to the entire body was over 20 rem. That's a significant amount of radiation. The LD50 for humans is about 500 rem. REM (Roentgen Equivalent, Man) is obsolete here. We now use the Sievert which is the same scale of measurement times 100. 1 Sievert = 100 REM

The NRC requires that the public recieve no more than 100 mrem per year above background. Employees are not allowed to recieve more than 5000 mrem per year

Same as here but there is an additional 5 year maximum of 10 rem. That is also considered a lifetime limit by many employers.

If you are young and have a choice between MRI, Ultrasound or CT scan, skip the CT scan. Older people are less likely to suffer long term side effects from radiation because they won't live long enough for it to be a problem and they are unlikely to have (more) children.

[Evan]

From the link that Rollin' provided:

Tsurutani said scientists can't yet accurately measure or predict what the strength or direction of Earth's magnetic field will be when a storm arrives

But he adds that the orientation of Earth's magnetic field would not be known. Future space-based observatories could address this blind spot in space weather forecasting.

Where's my Boy Scout compass? I hate it when I see such dumbass statements in print from a "magazine" that should know better. We know perfectly well what the orientation of the Earth's field is. What we cannot predict is the orientation of the trapped magnetic field in the coronal mass ejection.

[dp]

I have to believe the writer meant they couldn't predict the orientation of the "blob" relative to earth's magnetic field. That, at least, would be true.

[Evan]

Of course that is what was meant by the informant to the article. Why didn't the editor or more importantly the writer catch it? It's a glaringly obvious error. Gahh..

[dp]

Of course that is what was meant by the informant to the article. Why didn't the editor or more importantly the writer catch it? It's a glaringly obvious error. Gahh..

The way they slaughter the facts in the gulf leak and climate change, I've become quite accustomed to shrugging it off as a lost cause