Reykjavík Grapevine - 07.12.2012, Qupperneq 6

Reykjavík Grapevine - 07.12.2012, Qupperneq 6
6 The Reykjavík Grapevine Issue 18 — 2012 Iceland | Weather You’ve bathed in the murky waters of the Blue Lagoon, you’ve circled the Golden Circle and now you’d like to see the sky come alive with dancing green and red lights. Well, you’re not alone. A recent survey conducted for the Iceland Tourist Board found that 16.1% of tourists who visited the country thought the aurora borealis were the most memorable part of their trip. With support from the Ministry of Industry and Promote Iceland, the Icelandic Meteorological Office has begun forecasting the appearance and visibility of these northern lights, which will more than likely assist you in your planning. “There are a lot of particles, protons and electrons, coming at very high speeds from the sun,” says Dr. Þórður Arason, a geophysicist at the Met Of- fice, of the aurora. “The magnetic field of the earth is bombarded by these par- ticles.” The particles, brought to earth by solar storms, interact with oxygen and nitrogen in the atmosphere, and electrons are drawn to the north and south poles. As this happens certain elements are illuminated—oxygen creates a great glow and nitrogen cre- ates blue and purplish-red colours. In addition to measuring cloud cover and darkness (the presences of the moon) the Met Office’s forecasts predict the strength of the storms originating off the face of the sun, also known as space weather. Yes, space weather On March 13, 1989, the residents of Quebec, Canada, lost electricity for nine hours when the province’s power grid shut down. A few months later Toronto’s stock market screeched to a halt for three hours when their com- puter system crashed. In both cases, scientists blamed solar storms. Due to instances such as these, pre- dicting the frequency and intensity of these storms is done for practical pur- poses. “Most of this monitoring is not for measuring northern lights or an interest in predicting them,” Þórður says. “It’s because these things can inf luence power grids, satellites and all kinds of instruments.” The Met Of- fice, which doesn’t have the equipment necessary to create their own space weather predictions, uses reports cre- ated by the National Oceanic and At- mospheric Association, a US Federal Agency. The Met Office uses a scale of zero to nine to rank the intensity of aurora displays based on these predictions, with one being “quiet,” two being “low,” and three being “moderate.” The scale, however, does not accurate- ly describe what goes on in the sky. A note on the Met Office website states that “even grade 2 (low activity) can be beautiful and grade 3 (moderate) can be dazzling.” Over the course of the monitor- ing, Þórður notes that there have been northern lights displays on nights with low readings, “but stronger read- ings would give more colourful, vivid and dancing northern lights.” The most valuable and most ac- curate information the Met Office provides is the amount of cloud cover over Iceland. “About thirty percent of the time we have a cloud cover of half cloudy or less,” Þórður says. “Seventy percent of the nights are damaged by the clouds.” Myth busting Cloudiness and brightness are the big- gest disruptors of any northern lights display. The middle of winter may be the darkest time of the year in Ice- land, but according to Þórður, north- ern lights displays actually occur with greater frequency around the spring and fall equinoxes in March and Sep- tember, respectively. However, the oddest misconcep- tion, as well as the most hotly con- tested one, is whether or not the north- ern lights make sounds. “It seems to be quite common that people think they can hear noise from the aurora,” Þórður says. “The aurora are formed a hundred kilometres or higher above ground, and the air is so thin up there that it cannot create sound waves. Sound is not transmitted at that height.” If sound could be transmitted from that level, he added, the electrons would make a faint hissing sound. Unanimous agreement on the na- ture of the northern lights evades the scientific community and the actual audibility of the aurora is still up for debate. While most scientists would agree that the aurora are a soundless wonder, Unto Laine, a researcher at Aalto University in Finland, recorded this July a clapping sound in an area of high aurora activity, believed to be caused by the same particles causing the display in the sky. Most northern lights misconcep- tions centre on when and where it’s best to see them. While some intuitive knowledge on the subject is accurate (it’s easier to see the aurora away from light pollution) there’s a tendency to mistake coincidence for scientific fact. “There are a lot of people who kind of ‘know’ intuitively that you need to have cold to see them,” Þórður says. “I have often heard from people that you need to have a certain temperature in order to see the northern lights, which is wrong.” If not for the constant pres- ence of the sun during the summer months, it would be possible to see the lights in July. As Þórður says “There is always something going on here in Iceland, if you can see through the clouds and it’s dark, just wait.” “ About thirty percent of the time we have a cloud cover of half cloudy or less. Seventy percent of the nights are damaged by the clouds. „ “ I have often heard from people that you need to have a certain tempera- ture in order to see the northern lights, which is wrong „ Seeing The Light How do you predict a spontaneous natural phenomenon? Words by Arit John. Photos by Natsha Nandabhiwat The Iceland Met Office’s Northern Lights predictions can be seen at http://en.vedur.is/weather/forecasts/aurora/ Approximately every 11 years, the length of one solar cycle, the num- ber of sunspots on the outer layer of the sun reaches a maximum. With the maximum comes increased magnetic variation and more active space weather. The power outage and computer system crash that hit Canada both occurred during the solar maximum of 1989. And while it could spell bad news for satel- lites, the good news for aurora fans is that 2013 is expected to bring a higher frequency of northern lights. 1. One suggested that fires surrounded oceans of a flat earth and the lights were flames reflected on the sky. 2. Another theory held that glaciers absorbed power and began to glow. 3. The third, and closest, belief was that the sun projected its beams into the night sky. 1995 0 50 100 150 200 2000 2005 2010 2015 2013 2020 Taking It To The Max The Northern Lights outlook for 2013 is stellar Three Early Theories From the thirteenth century Norwegian text ‘Kongespeilet’

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