News tagged with lightning
Lightning is an atmospheric discharge of electricity accompanied by thunder, which typically occurs during thunderstorms, and sometimes during volcanic eruptions or dust storms. In the atmospheric electrical discharge, a leader of a bolt of lightning can travel at speeds of 60,000 m/s (130,000 mph), and can reach temperatures approaching 30,000 °C (54,000 °F), hot enough to fuse silica sand into glass channels known as fulgurites which are normally hollow and can extend some distance into the ground. There are some 16 million lightning storms in the world every year.
Lightning can also occur within the ash clouds from volcanic eruptions, or can be caused by violent forest fires which generate sufficient dust to create a static charge.
How lightning initially forms is still a matter of debate: Scientists have studied root causes ranging from atmospheric perturbations (wind, humidity, friction, and atmospheric pressure) to the impact of solar wind and accumulation of charged solar particles. Ice inside a cloud is thought to be a key element in lightning development, and may cause a forcible separation of positive and negative charges within the cloud, thus assisting in the formation of lightning.
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University of Cincinnati (UC) researchers have found that lightning may affect the onset of headache and migraines.
Diseases, Conditions, Syndromes Jan 24, 2013 | 4 / 5 (1) | 1 |
(Medical Xpress)—It's no accident that Dr. Aram Attarian is an expert on camping and outdoor adventure safety. Attarian, a professor of parks, recreation and tourism management at NC State University, has ...
Health Oct 22, 2012 | not rated yet | 0
About 24,000 people are killed by lightning every year, with about 10 times as many people injured. The Wilderness Medical Society has issued important new practice guidelines for precautions that can lower ...
Other Aug 28, 2012 | not rated yet | 0
As many as one-third of sufferers of migraine with aura experience forewarning symptoms even the day before an attack that might create an opportunity for intervention and prevention. Later during the actual migraine episode ...
Diseases, Conditions, Syndromes Jun 01, 2011 | not rated yet | 0