National Geographic News
The cities along the Gulf of Mexico are seen at night from the International Space Station.

The night lights of the U.S. Gulf Coast shine below the International Space Station in October 2010.

Photograph courtesy NASA

A coronal mass ejection from 2002.

A 2002 coronal mass ejection. Image courtesy SDO/NASA

Richard A. Lovett

for National Geographic News

Published March 2, 2011

On February 14 the sun erupted with the largest solar flare seen in four years—big enough to interfere with radio communications and GPS signals for airplanes on long-distance flights.

As solar storms go, the Valentine's Day flare was actually modest. But the burst of activity is only the start of the upcoming solar maximum, due to peak in the next couple of years.

"The sun has an activity cycle, much like hurricane season," Tom Bogdan, director of the Space Weather Prediction Center in Boulder, Colorado, said earlier this month at a meeting of the American Association for the Advancement of Science in Washington, D.C.

"It's been hibernating for four or five years, not doing much of anything." Now the sun is waking up, and even though the upcoming solar maximum may see a record low in the overall amount of activity, the individual events could be very powerful.

In fact, the biggest solar storm on record happened in 1859, during a solar maximum about the same size as the one we're entering, according to NASA.

That storm has been dubbed the Carrington Event, after British astronomer Richard Carrington, who witnessed the megaflare and was the first to realize the link between activity on the sun and geomagnetic disturbances on Earth.

During the Carrington Event, northern lights were reported as far south as Cuba and Honolulu, while southern lights were seen as far north as Santiago, Chile. (See pictures of auroras generated by the Valentine's Day solar flare.)

The flares were so powerful that "people in the northeastern U.S. could read newspaper print just from the light of the aurora," Daniel Baker, of the University of Colorado's Laboratory for Atmospheric and Space Physics, said at a geophysics meeting last December.

In addition, the geomagnetic disturbances were strong enough that U.S. telegraph operators reported sparks leaping from their equipment—some bad enough to set fires, said Ed Cliver, a space physicist at the U.S. Air Force Research Laboratory in Bedford, Massachusetts.

In 1859, such reports were mostly curiosities. But if something similar happened today, the world's high-tech infrastructure could grind to a halt.

"What's at stake," the Space Weather Prediction Center's Bogdan said, "are the advanced technologies that underlie virtually every aspect of our lives."

Solar Flare Would Rupture Earth's "Cyber Cocoon"

To begin with, the University of Colorado's Baker said, electrical disturbances as strong as those that took down telegraph machines—"the Internet of the era"—would be far more disruptive. (See "The Sun—Living With a Stormy Star" in National Geographic magazine.)

Solar storms aimed at Earth come in three stages, not all of which occur in any given storm.

First, high-energy sunlight, mostly x-rays and ultraviolet light, ionizes Earth's upper atmosphere, interfering with radio communications. Next comes a radiation storm, potentially dangerous to unprotected astronauts.

Finally comes a coronal mass ejection, or CME, a slower moving cloud of charged particles that can take several days to reach Earth's atmosphere. When a CME hits, the solar particles can interact with Earth's magnetic field to produce powerful electromagnetic fluctuations. (Related: "Magnetic-Shield Cracks Found; Big Solar Storms Expected.")

"We live in a cyber cocoon enveloping the Earth," Baker said. "Imagine what the consequences might be."

Of particular concern are disruptions to global positioning systems (GPS), which have become ubiquitous in cell phones, airplanes, and automobiles, Baker said. A $13 billion business in 2003, the GPS industry is predicted to grow to nearly $1 trillion by 2017.

In addition, Baker said, satellite communications—also essential to many daily activities—would be at risk from solar storms.

"Every time you purchase a gallon of gas with your credit card, that's a satellite transaction," he said.

But the big fear is what might happen to the electrical grid, since power surges caused by solar particles could blow out giant transformers. Such transformers can take a long time to replace, especially if hundreds are destroyed at once, said Baker, who is a co-author of a National Research Council report on solar-storm risks.

The U.S. Air Force Research Laboratory's Cliver agrees: "They don't have a lot of these on the shelf," he said.

The eastern half of the U.S. is particularly vulnerable, because the power infrastructure is highly interconnected, so failures could easily cascade like chains of dominoes.

"Imagine large cities without power for a week, a month, or a year," Baker said. "The losses could be $1 to $2 trillion, and the effects could be felt for years."

Even if the latest solar maximum doesn't bring a Carrington-level event, smaller storms have been known to affect power and communications.

The "Halloween storms" of 2003, for instance, interfered with satellite communications, produced a brief power outage in Sweden, and lighted up the skies with ghostly auroras as far south as Florida and Texas.

(Also see "'Nightmare' Star Flares Dim Odds for Alien Life?")

Buffing Up Space-Weather Predictions

One solution is to rebuild the aging power grid to be less vulnerable to solar disruptions.

Another is better forecasting. Scientists using the new Solar Dynamics Observatory spacecraft are hoping to get a better understanding of how the sun behaves as it moves deeper into its next maximum and begins generating bigger storms. (See some of SDO's first sun pictures.)

These studies may help scientists predict when and where solar flares might appear and whether a given storm is pointed at Earth.

"Improved predictions will provide more accurate forecasts, so [officials] can take mitigating actions," said Rodney Viereck, a physicist at the Space Weather Prediction Center.

Even now, the center's Bogdan said, the most damaging emissions from big storms travel slowly enough to be detected by sun-watching satellites well before the particles strike Earth. "That gives us [about] 20 hours to determine what actions we need to take," Viereck said.

In a pinch, power companies could protect valuable transformers by taking them offline before the storm strikes. That would produce local blackouts, but they wouldn't last for long.

"The good news is that these storms tend to pass after a couple of hours," Bogdan added.

Meanwhile, scientists are scrambling to learn everything they can about the sun in an effort to produce even longer-range forecasts.

According to Vierick, space-weather predictions have some catching up to do: "We're back where weather forecasters were 50 years ago."

Paul Geigle
Paul Geigle

Our biggest concern on thisplanet because there is absolutely nothing we can do about these solar events. 

George Reagan
George Reagan

I remember the hot dry days of the mid/late 1950s in the Texas panhandle town of Abernathy.  The winters were rather warm as I remember getting a new bicycle for Christmas in 1954 while wearing a T-shirt and shorts and riding the bike.  That coincides with the solar radiation chart shown.

I do believe the so called global warming/climate change (gw/cc) claims are a result of our Sun/Earth positioning variations (Milankovitch effect), the Solar variations and our own Earth's molten core and geothermal zones and volcanoes.  All of these extreme conditions cause complicated events to just "happen" randomly and are not human related.  The recent cooling period matches the charts years for low solar activity.  So why is the UN creating a false alarm for gw/cc???  It appears that throwing massive amounts of money at the expense of the hard working American tax payer will do nothing to "save the world from itself".  We need to back off from the new socialist theory of social and economic justice in the name of gw/cc. 

Phillip Mai
Phillip Mai


Steven Starr
Steven Starr

Another disaster-in-waiting would be the permanent loss of off-site power to nuclear power plants, which are not designed to function on a long-term basis using electricity produced by back-up on-site generators.  Reactors *must* keep their cooling systems (for both the reactor core and spent fuel ponds) in operation, even when the reactor is shut down. Take a look at Fukushima to see what happens when you fail to do so.

Imagine dozens of nuclear power plants all frantically attempting to provide on-site electric power to keep their cooling systems going for months on end.  Most reactors store only about 6 days worth of diesel fuel required to run the massive diesel generators that would provide such back-up power.  IF the diesel generators were capable of running continuously for months on end (they are not designed or expected to do so), there would still be the matter of trucking fuel to the plants to keep them running.

One step we could immediately take to reduce this danger is to remove older spent fuel rods from cooling ponds and put them into Hardened On-Site Storage (HOSS). Two-thirds of the spent fuel rods sitting in US reactor cooling ponds could now be removed and put into HOSS; doing this would greatly reduce the possible impact of a loss of coolant/cooling accident at a spent fuel pool. See  

Another scenario similar to the Carrington Event, also not currently addressed or considered, is the destruction of unprotected integrated circuits in the control systems of nuclear power plants by Electromagnetic Pulse (EMP) produced by a high altitude nuclear detonation.  Such a detonation over the East Coast of the US would hammer dozens of nuclear power plants.  Imagine 20 or 30 Fukushimas occurring simultaneously in the US.  Another little problem we haven't gotten around to dealing with.

Steven Starr

Senior Scientist, Physicians for Social Responsibility

John Swallow
John Swallow

@George Reagan :Great points that you make; but, there are those like Vivian Azurakin who would rather waste time, resources and energy trying to deal with a nonexistent problem, anthropogenic global warming, than to put the same effort into trying to mitigate something that has happened, will happen again and can be minimized if the plan is put in place to do so.

You mention the UN/IPCC:

Just what would you expect from an organization whose mandate is this?

1. Scope and Approach of the Assessment 1.1. Mandate of the Assessment

The Intergovernmental Panel on Climate Change (IPCC) was established by World Meteorological Organization and United Nations Environmental Programme (UNEP) in 1988 to assess scientific, technical, and socioeconomic information that is relevant in understanding human-induced climate change, its potential impacts, and options for mitigation and adaptation.

You say: "save the world from itself". And this is what  HL Mencken had to say about that:

“The desire to save humanity is always a false front for the urge to rule it” — HL Mencken

H.L. Mencken had it right:

"The whole aim of practical politics is to keep the populace alarmed -- and hence clamorous to be led to safety -- by menacing it with an endless series of hobgoblins, all of them imaginary."

Vivian Azurakin
Vivian Azurakin

@George Reagan Your argument is rubbish. All these factors have already been taken into account. And what "recent cooling period"? The last ten years have been the hottest in human history, and the temperature of the sea is steadily rising as well. The effect of rising levels of carbon dioxide on the Earth's temperature has been known for over a hundred years and can be duplicated in experiments you can do at home. Why are you babbling on about socialism? What does that have to do with it? We need a lot of equipment replaced and some new equipment installed. I seem to remember that capitalism is rather good at maximizing production, if nothing else. Why do you think capitalism would find it difficult to meet the challenges of global climate change? Capitalist societies have done this sort of job before, in building the atomic bomb and putting a man on the moon, to give only two examples. It's a pity that you're not a good enough capitalist to have the faith that these prior successes can be duplicated.  And I'll believe that the "hard working American tax payer" is urgently concerned about the money spent on his or her behalf when that taxpayer starts voting out Congresspeople who insist on spending money on weapons systems that even the Pentagon says it doesn't want

Jan Steinman
Jan Steinman

@Steven Starr it seems to me that a Carrington Event CME would have consequences similar to an EMP.

Most integrated circuits operate on 12 VDC or less. Their over-voltage protection is good for only a few joules. Any EMF induction capable of creating sparks on telegraph lines is certainly capable of overwhelming IC over-voltage protections.

And I'll bet that nuclear power plant backup generators are all controlled by microprocessors. But even if they employ old-fashioned electromagnetic relays, could those relays withstand an EMF capable of generating sparks? Most relays operate on 12 to 24 volts -- they would be fried by over-current if an EMP of a Carrington Event size hit.

We have optimized technology of terrible consequence for the optimal situation. Better hope nothing unusual -- like a tsunami in an earthquake zone -- happens. The next time, it might be tens or hundreds of reactors going into melt-down.

Timothy Maloney
Timothy Maloney

@Steven Starr  

Good observations.  All the more reason to shorten the wire-runs on the electric transmission grid by ISOLATING locales instead of making greater efforts to interconnect locales with a dispatchable "smart" grid as espoused by the National Renewable Energy Laboratory plan that aims for 80% renewables in USA by 2050. 

The voltage induced into a transmission grid loop by a solar flare is proportional to the AREA of the circuit, by Faraday's Law.  That area is equal to the distance between a pair of wires, 1 meter say, multiplied by the distance that the wires run between the generating plant (the step-up transformer) and the distribution station (the step-down transformer).  By interconnecting many intermittent generating facilities using long wire-runs, we increase the area of circuit loops and aggravate the induction problem from solar magnetic disturbances.

The reliable alternative is for consumers in a particular locale to be served by isolated, not interconnected, non-intermittent Liquid-Fuel Thorium Reactors which don't require an emergency backup cooling system.

see  or

John Swallow
John Swallow

@Vivian Azurakin

Vivian Azurakin: Since it is obvious that you  not want to look anything up your self, I will save you the trouble but already know that you are too ideologically crippled to understand this information that runs counter to your preconceived opinions.

9451600 Sitka, Alaska


No Trend In US July Temperatures Since 1895


temperature data

( – In a June 20 interview with Spiegel Online, German climate scientist Hans von Storch said that despite predictions of a warming planet the temperature data for the past 15 years shows an increase of 0.06 or “very close to zero.”



Santer originally calculated 17 years of no warming to show a discrepancy between models and global temperature.

In his new paper:

“The multimodel average tropospheric temperature trends are outside the 5–95 percentile range of RSS results at most latitudes.”

Phil Jones: “No global warming since 1995″

Richard Treadgold | February 14, 2010

 THE UN's climate change chief, Rajendra Pachauri, has acknowledged a 17-year pause in global temperature rises, confirmed recently by Britain's Met Office, but said it would need to last "30 to 40 years at least" to break the long-term global warming trend.


In a joint press conference NOAA and NASA have just released data for the global surface temperature for 2013. In summary they both show that the ‘pause’ in global surface temperature that began in 1997, according to some estimates, continues.

Statistically speaking there has been no trend in global temperatures over this period. All these years fall within each other’s error bars. 

When asked for an explanation for the ‘pause’ by reporters Dr Gavin Schmidt of NASA and Dr Thomas Karl of NOAA spoke of contributions from volcanoes, pollution, a quiet Sun and natural variability. In other words, they don’t know.

John Swallow
John Swallow

@Vivian Azurakin "The effect of rising levels of carbon dioxide on the Earth's temperature has been known for over a hundred years and can be duplicated in experiments you can do at home."Then show me the experiment.You can not because it has never been done.

Vivian Azurakin  or any of the other alarmist on here  needs to provide us with the experiment that shows that CO2 does what some maintain as far as being the driver of the earth's climate. I do not need to be reminded of Tyndall's 1859 lab experiments that do not prove that humanity's CO2 emissions are warming the planet. In the real world, other factors can influence and outweigh those lab findings and that is why these experiment must deal with the real world and not computer models that do not have the ability to factor in all of the variables that effect the earth's climate. If they can not provide a verifiable experiment regarding the present amount of CO2 in the atmosphere and how it effects the climate and creates their anthropogenic global warming, then believing that it does so is akin to believing that Santa Clause is real and you need to be good to get something left under the tree.

It is a fact that real scientist devise experiments to either prove or disprove their hypotheses and welcome people to try to disprove them so that they can move on. They sure do not say that the science is settled and the argument is over because there are REAL scientist out there doing REAL scientific work that are not blinded by some agenda that they support so that they can get more "research" money or money to fund a boondoggle renewable energy scheme that will never work.

Wise up, please.

George Reagan
George Reagan

@Jan Steinman @Steven Starr

Since most modern solid state electronics use current and voltages on the order of milliamps millivolts, the problems are compounded without any radiation shielding.  Most new systems use multilayer protection. 


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