Solar flares produce high-energy particles and radiation that are dangerous to live organisms. However, at the surface of the Earth, we are well protected from the effects of Solar flares and other solar activity by the Earth’s magnetic field and atmosphere. The most dangerous emissions from flares are energetic charged particles (primarily high-energy protons) and electromagnetic radiation (primarily x-rays).
The x-rays from flares are stopped by our atmosphere well above the Earth’s surface. They do disturb the earth’s ionosphere, however, which in turn disturbs some radio communications. Along with energetic ultraviolet radiation, they heat the Earth’s outer atmosphere, causing it to expand. This increases the drag on Earth-orbiting satellites, reducing their lifetime in orbit. Also, both intense radio emission from flares and these changes in the atmosphere can degrade the precision of Global Positioning System (GPS) measurements.
The energetic particles produced at the Sun in flares seldom reach the Earth. When they do, the Earth’s magnetic field prevents almost all of them from reaching the Earth’s surface. The small number of very high energy particles that do reach the surface does not significantly increase the level of radiation that we experience every day.
The most serious effects on human activity occur during major geomagnetic storms. It is now understood that the major geomagnetic storms are induced by coronal mass ejections (CMEs). Coronal mass ejections are usually associated with flares, but sometimes no flare is observed when they occur. Like flares, CMEs are more frequent during the active phase of the Sun’s approximately 11-year cycle. The last maximum in solar activity, the maximum of the current solar cycle, was in April 2014.
Coronal mass ejections are more likely to have a significant effect on our activities than flares because they carry more material into a larger volume of interplanetary space, increasing the likelihood that they will interact with the Earth. While a flare alone produces high-energy particles near the Sun, some of which escape into interplanetary space, a CME drives a shock wave that can continuously produce energetic particles as it propagates through interplanetary space. When a CME reaches the Earth, its impact disturbs the Earth’s magnetosphere, setting off a geomagnetic storm. A CME typically takes 3 to 5 days to reach the Earth after it leaves the Sun. Observing the ejection of CMEs from the Sun provides an early warning of geomagnetic storms. Only recently, with SOHO, has it been possible to continuously observe the emission of CMEs from the Sun and determine if they are aimed at the Earth.
One serious problem that can occur during a geomagnetic storm is damage to Earth-orbiting satellites, especially those in high, geosynchronous orbits. Communications satellites are generally in these high orbits. Either the satellite becomes highly charged during the storm and a component is damaged by the high current that discharges into the satellite, or a component is damaged by high-energy particles that penetrate the satellite. We are not able to predict when and where a satellite in a high orbit may be damaged during a geomagnetic storm.
Astronauts on the Space Station are not in immediate danger because of the relatively low orbit of this manned mission. They do have to be concerned about cumulative exposure during spacewalks. The energetic particles from a flare or CME would be dangerous to an astronaut on a mission to the Moon or Mars, however.
Another major problem that has occurred during geomagnetic storms has been the temporary loss of electrical power over a large region. The best-known case of this occurred in 1989 in Quebec. High currents in the magnetosphere induce high currents in power lines, blowing out electric transformers and power stations. This is most likely to happen at high latitudes, where the induced currents are greatest, and in regions having long power lines and where the ground is poorly conducting.
These are the most serious problems that have occurred as a result of short-term solar activity and the resulting geomagnetic storms. A positive aspect of geomagnetic storms, from an aesthetic point of view, is that the Earth’s auroras are enhanced.
The damage to satellites and power grids can be very expensive and disruptive. Fortunately, this kind of damage is not frequent. Geomagnetic storms are more disruptive now than in the past because of our greater dependence on technical systems that can be affected by electric currents and energetic particles high in the Earth’s magnetosphere.
Could a solar flare or CME be large enough to cause a nation-wide or planet-wide cataclysm? It is, of course, impossible to give a definitive answer to this question, but no such event is known to have occurred in the past and there is no evidence that the Sun could initiate such an event.
Heliobiology is a new branch of science that deals with the influences on human health caused by solar activity and investigates the possible mechanisms to explain the reported associations. In the last decades, many researchers have considered geomagnetic storms, cosmic rays, and Solar flares to be hazardous to human health. They have established that these space weather indicators could play a role in regulating external factors in human health. Heliobiological results have attracted scientists from various branches of science to do more work in this field. In this short paper, the concepts of solar activity, space weather, and heliobiology will be briefly introduced and discussed. The main findings of the effects of solar activity on human health will be summarized in this post.
Solar flares and Medicine
For thousands of years, medical practitioners have speculated that human maladies might be correlated with environmental cycles. For example, certain times of the night and certain phases of the moon were thought to be riskier for patients than other times. Modern research, however, has failed to confirm the significance of any such correlations—that is, until just three months ago.
Thanks to two long-term studies in human physiology and pathology, researchers uncovered correlations between human health and the sunspot cycle (see figure 1). The research team, headed up by William Hrushesky of the University of South Carolina, first analyzed nearly 1.2 million consecutive, serially independent screening Pap smears from the health records of Dutch women that spanned from January 1983 through December 2003. This screening program included one-third of all adult females living in southern Holland with both urban and rural women of all adult ages fully represented.
Here, the team determined the incidence of six infectious, premalignant, and malignant changes in the cervical epithelium. Additionally, the team examined records of physiologic functions (oral temperature, pulse rate, systolic and diastolic blood pressure, respiration rate, and peak expiratory flow) of a healthy man (a biomedical scientist living in St. Paul, Minnesota) measured fives per day throughout the same 21-year period.
Recent sun activities.
The sun’s been a bit of a show-off lately. On the heels of its magnificent total eclipse last month, yesterday it produced the biggest solar flare recorded in the last 12 years. This and other flares in recent days have caused a radio blackout and “shock arrivals” of radiation from the sun, according to NASA, as part of a geomagnetic storm expected to continue for the next few days. (Two more mid-level Solar flares have been reported so far today.)
Radio blackouts and shocks of radiation sound kinda scary and previous Solar flares have caused problems like transformer explosions and widespread mobile-phone outages. So of course we wondered: What does all of this mean for our health? The good news, experts say, is probably not much.
NASA about Solar Flare
First things first, what is a solar flare? According to NASA, it’s a sudden and intense flash of brightness that occurs when magnetic energy built up in the solar atmosphere is released. High-energy particles and a burst of ultraviolet rays are released into space, and in a few days can reach the Earth’s atmosphere.
NASA also says that these powerful bursts of radiation are nothing to worry about from a health perspective. “Harmful radiation from a flare cannot pass through Earth’s atmosphere to physically affect humans on the ground,” the space agency said in a statement today, “however—when intense enough—they can disturb the atmosphere in the layer where GPS and communications signals travel.”
Dale Gary, Ph.D., distinguished professor of physics at NJIT’s Center for Solar-Terrestrial Research, agrees with NASA’s reassuring statement. “There are potential health effects for anyone exposed to that high-energy radiation, but actually we are protected because those rays and particles get absorbed into our atmosphere,” says Gary.
People on airplanes flying at high altitudes over the poles might be at increased risk for some of this radiation, Gary continues, and he says that occasionally, flight routes are changed during periods of unusual solar activity to protect against this. But for anyone on the ground, he says, there’s not much to worry about.
In addition to a large dose of radiation, however, Solar flares also cause fluctuations in magnetic fields, which can reach the earth’s surface. “These take a couple of days to get here, but when they arrive they can interact with our magnetosphere,” says Gary. “That can induce currents in our power lines, and when that happens, transformers can blow or power outages can occur.”
Solar flares are harmless or dangerous?
According to National Geographic, scientists predict that one of these strong storms hit our planet every month or so. People in high-latitude regions may also be treated to brilliant auroras, or visible lights in the sky, over the next few days after a solar flare-up.
Still, these storms probably won’t cause any health problems—except that there could be safety issues if the power goes out, Gary says. GPS and traffic-light outages could make for risky driving, for example, or hospitals could theoretically lose access to health data.
Not everyone is convinced that Solar flares are harmless, however. A 2014 study published in the journal Stroke found a link between geothermal storms and stroke risk among people in New Zealand, Australia, the United Kingdom, France, and Sweden. The study compared 11,453 hospital reports with daily geomagnetic activity over a 23-year period and found that geomagnetic storms were associated with a 19% increased risk of stroke overall, and a 27% increased risk among adults under 65.
The study could not show a cause-and-effect relationship, and the researchers—from the Auckland University of Technology, the University of Auckland, the University of Oxford, and other institutions—did not have detailed information for all participants about their traditional cardiovascular risk factors. But they speculate that magnetic fluctuations could have an effect on blood pressure, heart rate, blood clotting ability, or circadian rhythms, any of which could have an effect on stroke risk.
Gary, for what it’s worth, has his doubts. “The change in the magnetic field we’re talking about is really small,” he says: “If you think of the magnetic field that causes your compass needle to point north, we’re talking about a tenth of a percent of that fluctuation.” Those tiny changes are amplified by our giant power grid, he says, but they’re unlikely to have an effect on an individual human body.
Even if the study’s assumptions are correct, geomagnetic storms only accounted for less than 3% of all strokes during the study’s timeframe. Considering nearly 17 million strokes occur around the world every year, however, that’s almost half a million people. “Although the effect of geomagnetic activity alone is modest,” the authors wrote in their paper, “in combination with other risk factors, it could be extremely important.”
The authors suggest that geomagnetic storm warnings be announced along with weather reports and that doctors and patients should pay closer attention to controlling conventional risk factors for stroke during the days leading up to these types of solar events. These actions, they say, may reduce stroke incidence on a global level.
The results from heliobiological investigations carried out in the last 20 years have reported evidence that suggests solar activity has direct or indirect influences on human health. Although there are speculations about the reality of such relationships, the results have attracted the scientific community to heliobiology and encouraged them to conduct more research in this field and search for mechanisms that can explain such relationships. For more conclusions to be made in the field of heliobiology, more investigations and medical data from different places around the world are needed. In this regard, a national-scale project led by the first author of the scientific research known as The Effects of Solar Activity and Geomagnetic Disturbance on Human Health has been proposed and submitted to the Ministry of Health and other research organizations. The main aim of this project is to investigate the effects of solar activity parameters on physiological and mental disorders and other parameters related to human health status.
Some people are more sensitive to solar storms than others. Super-sensitivity makes these people react to even light storms that happen 2-3 times/month. During a severe solar flare, they may experience significant medical conditions such as the rise of blood pressure, arrhythmia, migraines, sleeplessness, and on rare occasions sudden death.
Those people may need special attention and treatment. While western medicine doesn’t have an answer and thus trying to hide possible deterioration in response to solar storms, holistic medicine may help.
For evaluation and treatment of oversensitivity to flare-ups of the sun contact Philadelphia Holistic Clinic (267) 384-3085 and make an appointment with Dr. Tsan.