Surprising lightning observation

[Ivan Seeking]

Tonight I happened to check a "live" lightning map for activity, and noticed something odd. In about five separate areas of activity over the State of Oregon, separated by hundreds of miles and the Cascade mountains, the strike rate of all systems were changing, but ~equal, over a period of an hour. The colors didn't translate well from the screen shots, but it was clear that In the first frame linked, we see all as orange, which indicates a strike rate of between 90 and 120 per hour. In the next frame we see all as yellow, which represents a rate of 60-90 strikes per hour, and then we see all as white [it is a bit difficult to see but they are all still there], which represents 30-60 strikes per hour. Given that we would expect different heating and cooling cycles, different temperatures, different wind conditions, and even different times for sunset, why would the activity in lightning distributed so widely track so evenly?

This is the link I was using. This all comes from the animated map.
http://www.accuweather.com/maps-lig...cuweather&traveler=0&range=1&large=1&level=NW

Here is the first shot from 11:41 PM local time
http://img295.imageshack.us/img295/6126/lightning1ww3.jpg

This is the second shot from 12:11 AM
http://img295.imageshack.us/img295/6736/lightning2ud4.jpg

And this the third shot from 12:41 AM
http://img84.imageshack.us/img84/986/lightning3vw2.jpg

 

[Ivan Seeking]

The weather was coming from S by SE, so perhaps this results from the collision of two fronts or temperature zones?

 

[LURCH]

Wow, that really is odd. Did you have access to temperature information for those times? As you say, we would expect different temperatures in the different locations, but do we know they were different?

 

[Ivan Seeking]

I did take a look at temps and saw a range of about ten degrees between the West and East side of the Cascades - 55 to 65 degrees. I guess I should have compared North to South.

I noticed the current map shows an isolated area of activity in Canada following the same pattern - orange to yellow to white - over the course of an hour.

 

[Xezlec]

I knew a physics grad student (crazily smart guy) in college who was researching lightning. He told me that it had been computed that there was not nearly enough potential difference between cloud and ground to cause lightning strikes, and that it was either "known" or "very highly suspected" by scientists that all lightning results from the ionizing effect of cosmic rays (I seem to recall muons mentioned by name) streaking down from space providing a path for current to flow. He further explained that this theory was not yet complete, then stated quite melodramatically that he "believed lightning had a secret" and he was going to find it. Using giant lasers. Somehow. I think he was actually disappointed that there wasn't a sudden thunderclap after he said this.

Anyway, I believe he mentioned that one of the pieces of evidence for this was that it had been observed that lightning frequency correlates perfectly with the rate at which cosmic rays are observed for a given area of Earth's surface at a given time.

I believe this would explain your observation.

 

[Ivan Seeking]

Interesting. I was aware of the notion of cosmic rays playing a role, but I had never heard of this correlating to strike frequency.

Right now I am seeing the same effect over the entire NW US, and part of Canada.
http://img356.imageshack.us/img356/5535/lightning4zx3.jpg

Again, orange to yellow to white, in one hour, across the board. My first thought would be that there is something wrong with the map, but to a limited extent I know it to be accurate.
http://www.accuweather.com/maps-lig...cuweather&traveler=0&range=1&large=1&level=NW

 

[Ivan Seeking]

And sure enough, it is holding true at the national level. [Active map linked]
http://www.accuweather.com/maps-lig...cuweather&traveler=0&range=1&large=0&level=US

 

[Ivan Seeking]

It is most likely that there is something wrong with the map. It seems that the sequence is the same no matter what time I look.

 

[Xezlec]

Shame. The cosmic weather thing was cooler.

 

[blimkie.k]

He told me that it had been computed that there was not nearly enough potential difference between cloud and ground to cause lightning strikes, and that it was either "known" or "very highly suspected" by scientists that all lightning results from the ionizing effect of cosmic rays (I seem to recall muons mentioned by name) streaking down from space providing a path for current to flow.

I believe this would explain your observation.

Yea I read an article on this conecpt in a science magazine 2 years ago found it quite interesting. Here is a link to Janurary Scientific American Article relating to it if anyone is interested.


http://www.sciam.com/article.cfm?id=experts-do-cosmic-rays-cause-lightning