Posts Tagged ‘Carrington’
Wishing Upon A Star
October 17th, 2016 | 
Author: 
My love for radio began at an early age when I first started to tune the shortwave bands at age eleven. Little did I know then, that I was listening near the peak of the strongest solar cycle in recorded history, monster Cycle 19.
I thought that what I was hearing was normal for shortwave and that it would always be this way ... and it was, for a number of years.
As the solar cycle slowly declined, I began to take a deeper interest in propagation and its relationship with the Sun. After obtaining my licence and getting on the air, the reality set in with the arrival of a rather dismal Cycle 20. Following the vagaries of propagation became almost a hobby in itself, trying to correlate what I was observing with what the Sun was doing and even getting comfortable with predicting what might happen next.
It was particularly exciting during the stronger Cycles (21-23), to watch the dramatic effect of solar radiation on the F layer during the peak winter years of these cycles. With a major interest in 50MHz, watching the solar flux became a daily ritual, along with the fascinating daily rise of the F2 MUF as the Sun peaked over the horizon.
On normal mornings, around sunrise, the MUF would typically start close to 28MHz and slowly begin to rise over the next few hours. Often it would slow and settle-in between 38 and 42MHz, stay there for most of the day and then slowly recede as darkness approached.
I found myself looking forward to and wishing for more solar flares, along with the solar flux boost that inevitably followed.
On these mornings, the MUF would often be at 35MHz or higher, right at sunrise ... and begin climbing. Some days it would shoot-up like a rocket and in a matter of minutes would be at 50MHz or above, bringing thundering signals from the east coast not long after dawn. On other mornings it would climb much more slowly, receding and then advancing again, surging higher and then lower, as it teased its way towards the magicband. It was as if the ionosphere was a living breathing entity, as the solar radiation danced a slow tango with the critical frequency of the moment. Often it would stop at around 48 or 49MHz, stay there for several hours and then collapse ... no 6m excitement that day.
A nice bonus of watching this live interaction between the Sun and our ionosphere, was listening to the communications in the range between 28MHz and 50MHz as I followed the rising MUF. This was, and still is to a lesser extent, utilized on FM by paramedics, fire and police services throughout the U.S. It was not uncommon to hear mobile units enroute to an emergency, with sirens blazing in the background. Southern drawls usually meant that any 6m openings would begin in the southern states or the Caribbean, while Boston or New York accents, would herald an opening to New England or the possibility of trans-Atlantic openings to Africa or Europe. I became even more familiar with the daily interaction of the solar wind and how it affected radio ... and found it fascinating.
But just as the Sun affects propagation so positively, I was recently soberly reminded of how 'unfriendly' it can be ... as it has been in the past and will be again in the future. An article in this month's 'Astronomy', by Bob Berman, discussed threats to global welfare and in particular, a modern day repeat of the Carrington Event of 1859.
This was a double mega-flare and CME, taking only 19 hours to reach earth, compared to the normal 3-day trip. It was the strongest impact on earth ever recorded and one that will be repeated ... and is almost, statistically 'overdue', unless we dodged it in 2012 when a storm of similar magnitude missed the earth.
In Berman's words:
"What would a Carrington-level event do today, with our ubiquitous power lines, transformers, and more than a thousand operational satellites? In 2008, the U.S. government convened a panel of experts, who concluded that such a storm would completely destroy our electric grid. It would require two to 10 years to repair and cost about $2 trillion. We'd be knocked back to the stone age.
That panel panel called Carrington a "low frequency/high consequence" event - the kind humans typically ignore until it happens."
We quickly release how dependent on the hydro system we have become, when our power goes out for a few hours or even a day or two, following a severe weather event. Such an event is certainly 'inconvenient' but soon forgotten when the power returns. Going without power, and its trickle-down effects on our depended-upon infrastructures for several months or longer, would not be just 'inconvenient'. It would be a life-altering.
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| courtesy: http://www.solen.info/solar/ |
Maybe I'd better stop wishing for flares.
Carrington Probabilities
K7RA's 'Solar Update' in this week's ARRL News, mentions Jeff Foust's recent article in 'The Space Review', reminding us again of the dangers posed by a modern-day 'Carrington Event', also known as the 'Solar Storm of 1859'. A large solar flare in late August, hurled a monster-sized CME towards earth, making the 93 million mile journey in just 17.6 hours compared with the more normal rate of several days.
Huge auroras soon lit up the sky as far as central Mexico, Hawaii and the Caribbean. The aurora was so bright, it was reported that Rocky Mountain goldminers awoke in the middle of the night, and thinking morning had arrived, started to prepare breakfast. Telegraph lines and equipment burst into flame while some circuits continued to be usable with power supplies completely disconnected. The 1859 event still remains the most geoeffective solar storm since records have been kept.
Such an event today, of course, would wreak much more havoc ... probably having devastating consequences for decades and causing trillions of dollars of damage.
From Foust's article:
Was that, though, just a fluke event? .... Pete Riley, senior research scientist at Predictive Science Inc., offered a probabilistic forecast for the likelihood of another Carrington-like event, based on that storm’s estimated strength and measurements of the actual strength of solar storms over the last few decades. “If you the (sic) time between events, you can calculate the probability of the next event occurring within some unit of time,” he explained.
His estimate of the probability of another Carrington event is surprisingly high: about a 10 percent chance of such an event occurring over the next decade. “Ten percent is very, very high,” said William Murtaugh, assistant director for space weather at the White House’s Office of Science and Technology Policy (OSTP) ... “A one-percent probability over the course of the next one hundred years of a storm with an impact of that magnitude is considered very, very high and will motivate action.”
Interestingly, for this prediction, the actual strength of the solar storm of 1859 can only be estimated. If it was actually twice as strong as thought, then the probabilities drop from a (decade) 10% probability to just a 1% chance.
The U.S. government has recently set up a NASA multi-million budget funding proposal to study the likely effects of future large scale impacts and possible “response and resiliency capabilities” but it's not known if these will carry over to any new administration.
“Fortunately in space weather there’s no real politics,” Murtaugh said. “Both sides of House, both sides of the Senate, Republicans and Democrats, are both keen to work together to do something about this issue.”
The article has brought some interesting 'food for thought' comments, among them:
I think it is excellent that there are steps being taken to improve our understanding of the probabilities and predictive accuracy of such solar events, but I'm concerned that it isn't entirely clear how that information will translate into major investments in civil engineering that will make us less vulnerable to them. As for asteroidal impact threats, it's one thing to have a observations and research that will provide predictive information, and another to prevent tragedy. In both cases, it's about how we'll actually prevent such destructive effects once predicted. Prevention is a LOT more expensive than prediction, and is thereby ripe for threat denialism, which seems to be an emotion that has thoroughly infected at least the leaders of our nation.
It's a little funny about how much energy is being spent advocating human spaceflight for colonization and settlement as a means to save the species, but so little is being devoted to specific threats to the species, and to individuals in particular. I could get killed in an asteroidal impact or a severe geomagnetic storm, but sending a shipload of people to Mars sure isn't going to protect me.
I am a member of Infragard, which is dedicated to supporting efforts to protect us from risks to our electrical grid and other critical infrastructure. A novel "One Second After" by William R. Forstchen accurately illustrates the effects of a similar intentional attack on our grid and how it creates a cascading collapse of our society. Gas stations cannot pump gas, food rots in the stores, more food cannot be delivered to all the needed locations, and the people who know how to fix things cannot reach where they are needed and also starve to death. The result of a severe Carrington event with no effective preparation or protection for the giant transformers could thus cause most of our population to starve in a few months. This risk is about 1% to 0.5 % per year and is like having everyone playing Russian roulette once a year with 200 pistols where just one is loaded.
A modern day 'Carrington repeat' does indeed give pause for thought but perhaps the generally predicted upcoming 'grand solar minimum' will buy scientists some extra time to come up with solutions for what will eventually occur ... and, one more thing's for certain ... it'll be a heck of an aurora!
It's a little funny about how much energy is being spent advocating human spaceflight for colonization and settlement as a means to save the species, but so little is being devoted to specific threats to the species, and to individuals in particular. I could get killed in an asteroidal impact or a severe geomagnetic storm, but sending a shipload of people to Mars sure isn't going to protect me.
I am a member of Infragard, which is dedicated to supporting efforts to protect us from risks to our electrical grid and other critical infrastructure. A novel "One Second After" by William R. Forstchen accurately illustrates the effects of a similar intentional attack on our grid and how it creates a cascading collapse of our society. Gas stations cannot pump gas, food rots in the stores, more food cannot be delivered to all the needed locations, and the people who know how to fix things cannot reach where they are needed and also starve to death. The result of a severe Carrington event with no effective preparation or protection for the giant transformers could thus cause most of our population to starve in a few months. This risk is about 1% to 0.5 % per year and is like having everyone playing Russian roulette once a year with 200 pistols where just one is loaded.
A modern day 'Carrington repeat' does indeed give pause for thought but perhaps the generally predicted upcoming 'grand solar minimum' will buy scientists some extra time to come up with solutions for what will eventually occur ... and, one more thing's for certain ... it'll be a heck of an aurora!
