Solar flares effect on Earth 4

[0707]

“Solar activity rises and falls in 11-year cycles, swinging back and forth between times of quiet and storminess. Right now the sun is quiet. "We're near the end of Solar Cycle 23, which peaked way back in 2001. The next cycle, Solar Cycle 24, should begin "any time now," returning the sun to a stormy state.”

Why solar flares affect earth communications and electrical conductors?

Is there the possibility of global communication and electrical transformers damage if an extreme solar flare reaches the earth in the near future? Or mass media needs to explore these matters to sell these concepts?

luis

 

[epoisses]

As far as I know the height of a solar flare is << the diameter of the sun. I've never read about any effects on earth communications and electrical conductors but it is known that solar flares affect the earth climate.

 

[ivymike]

solar flares eject large amounts of charged particles, which can have a devastating impact on satellites. Terrestrial devices are largely protected by the earth's magnetic field, but a large solar storm can still scramble 'em.

 

[Comcokid]

As the charged particles travel the lines-of-force of the Earth's magnetic field they crash into the upper atmosphere mostly at the poles freeing electrons, and creating auroras. Additionally, long power transmission lines in in higher latitudes can pick up this charge, which can then overload the grid. It also happens at lower latitudes, but there's not much power grid to be affected at the tip of South America. Australia is a little more north.

Additionally, this changes the upper atmosphere. Most longer-wavelength communications (i.e. AM radio, shortwave, and others) depends upon reflection in the ionosphere to propagate. The result is that shortwave systems then communicate little more than line-of-sight.

 

[TheTick]

I once saw a show (Nova?) about solar flares and thei effect on earth. They can do real damage at ground evel. One example was a large flare that disabled a power grid in Quebec.

 

[electricpete]

Yes. The biggest recent damage was 1989 in the Northeast and Quebec.

One effect of the charged particles mentioned is a dc voltage gradient induced in the earth's crust.

For systems with short length of transmission line between grounded-wye transformers, there is not a lot of room for voltage to build up (voltage difference is gradient times distance)

For systems with long uninterrupted east/west lines, there can be a higher dc voltage. Transformers don't particularly like dc voltages applied to their terminals. Salem nuclear plant in New Jersey lost a generator stepup transformer during that 1989 event due to core oeverheating from that dc component.

google "geomagnetically induced current"

=====================================
Eng-tips forums: The best place on the web for engineering discussions.

 

[electricpete]

Is there the possibility of global communication and electrical transformers damage if an extreme solar flare reaches the earth in the near future? Or mass media needs to explore these matters to sell these concepts?

I think utilities and operators of communciations systems unerstand the phenomenon and have invested suitably to minimize the risk to their interests. I don't think any disruptions in the future will be smaller than what has occurred in the past since systems are made better and better. I don't know what you mean by mass media.

=====================================
Eng-tips forums: The best place on the web for engineering discussions.

 

[0707]

In the Google I found the topics bellow, which can be useful for our discussion.
When I said “mass media” I was speaking about press, TV, cinema and web. As this subject is controversial some times it can be explored sensuously in wrong ways, not to inform, but only by commercial reasons.

The intense radiation from a solar flare travels to Earth in eight minutes. As a result:

· The Earth's upper atmosphere becomes more ionised and expands.

· Long distance radio signals can be disrupted by the resulting change in the Earth's ionosphere.

· A satellite's orbit around the Earth can be disturbed by the enhanced drag on the satellite from the expanded atmosphere.

· Satellites' electronic components can be damaged.

Ionisation

The process by which ions are produced, typically occurring by collisions with negatively charged elementary particle that normally resides outside (but is bound to) the nucleus of atoms ("collisional ionization"), or by interaction with radiation that travels through vacuous space at the speed of light and propagates by the interplay of oscillating electric and magnetic fields. This radiation has a wavelength and a frequency. (electromagnetic radiation "photoionization").

Ionosphere

The region of the Earth's upper atmosphere containing a small percentage of free electrons and ions produced by photoionization of the constituents of the atmosphere by solar ultraviolet radiation. The ionosphere significantly influences radiowave propagation of frequencies less than about 30 MHz.

Damaging Earth Currents

The earth is a conducting sphere with a corresponding magnetic field. When solar plasma is spit our way, it flexes the earth's magnetic field, and this can induce voltages (and currents in closed circuits).
Perhaps you remember a science project where a wire was moved through a strong magnetic field and a voltage was detected between the ends of that wire. The same thing happens with geomagnetic disturbances, except the wire is a power company's transmission line, and instead of moving the wire, the magnetic field is moving while the transmission line remains stationary.
The frequency of the science project voltage depended on how fast you could reverse the direction you moved the wire. During severe geomagnetic storms, values of 2 to 10 volts per mile can be induced in transmission lines with corresponding GICs (Geomagnetic induced current) in excess of 100 amperes. The frequency of GICs is very low (one to a few milliHertz) compared to our normal line frequency of 60 Hertz — and that's part of the problem, at least for large transformers.


luis

 

[ivymike]

it can be explored sensuously in wrong ways
Based on what I've seen on the internet, there are lots of things that THAT can be done to, but I didn't think this was one of them!

 

[Jabberwocky]

I'm not worried about the solar flares per se, but I remember seeing quite a few documentaries about the Earth's magnetic field. They were doing fossil studies and found out that every 20k years or so the field switched polarity for some reason. Supposedly we are due in the next couple hundred years for this to happen.

If the field has to swap polarity, won't there be an amount of time when it is effectively zero strength? THEN what happens to us from solar flares?

 

[0707]

For earth core go to:

http://www.crystalinks.com/coreshift.html

What happens in the exact moment of earth reverse polarity?

Maybe we will suffer a radiation peak. Maybe boats, planes and birds will get lost. Maybe it will cause disturbance of Coriolis force and because of that we will have an increase or change of hurricanes occurrence.

If earth reverse polarity coincides with a solar flare all the above occurrences will be potentated

“NASA predicts that, rather than declining to zero gauss, the magnetic field would become disordered. Thus we might for short time have more than one north and South Pole on the planet. This official scientific stance says that the magnetosphere, which shields us from cosmic radiation, would not entirely disappear either. Thus, while communications would be erratic and perhaps at times completely inactivated, humans would find ways to survive. However, there are dissenters in the ranks, pointing to the vast South Atlantic magnetic anomaly and radiation damage to satellites over that region attributed to weakening of the protective magnetosphere.”

 

[Comcokid]

This is what I wonder about. Mars doesn't have much of an atmosphere. This is supposedly a result of no global magnetic field - the solar wind slowly strips off the upper atmosphere.

Now, on Earth, every few millennia the magnetic field reverses, and it takes a few years declining and rebuilding during each occurance.

A How much atmosphere is stripped off during each event?

B Given the number of times this has probably happened over 4 billion years, how much atmosphere was there in past history?

C How many more millennia can this continue without severly affecting the atmosphere, or will the sun burn out first?