| This article needs additional citations for verification. Please help improve this article by adding reliable references. Unsourced material may be challenged and removed. (September 2009) |
A megacryometeor is a very large chunk of ice which, despite sharing many textural, hydro-chemical and isotopic features detected in large hailstones, is formed under unusual atmospheric conditions which clearly differ from those of the cumulonimbus cloud scenario (i.e. clear-sky conditions). They are sometimes called huge hailstones, but do not need to form in thunderstorms. Jesus Martinez-Frias, a planetary geologist at the Center for Astrobiology in Madrid, pioneered research into megacryometeors in January 2000 after ice chunks weighing up to 6.6 pounds (3.0 kg) rained on Spain out of cloudless skies for ten days.
Contents |
Mass
More than 50 megacryometeors have been recorded since the year 2000. They vary in mass between 0.5 kilograms (1.1 lb) to more than 200 kilograms (440 lb). One in Brazil weighed in at 220 kilograms (490 lb).[1]
Formation
The process that creates megacryometeors is not fully understood, mainly in relation with the atmospheric dynamics necessary to produce them. They may have a similar mechanism of formation to that producing hailstones.[2] Scientific studies show that their composition matches normal tropospheric rainwater for the areas in which they fall. In addition, megacryometeors display textural variations of the ice and hydro-chemical and isotopic heterogeneity, which evidence a complex formation process in the atmosphere. It is known that they do not come from airplane toilets because the large chunks of ice that occasionally do fall from airliners are distinctly blue due to the disinfectant used. However, others have speculated that these ice chunks must have fallen from aircraft fuselages[2] after plain water ice accumulating on those aircraft through normal atmospheric conditions has simply broken loose. However, similar events occurred prior to the invention of aircraft. Studies indicate that fluctuations in tropopause, associated with hydration of the lower stratosphere and stratospheric cooling, can be related with their formation.[3] They are sometimes confused with meteors because they can leave small impact craters.
References
External links
- Megacryometeors: Resource Site
- Megacryometeors.com
- News Report: Ice Chunk Hits Oakland, CA, USA
- News Report, July 8, 2006: Ice Chunk hits South Africa
- Megacryometeors: fall of atmospheric ice blocks from ancient to modern times
- The Peculiar Phenomenon of Megacryometeors
- Sandton ice ball fell out of clear sky, says scientist
- Megacryometeors: Scientific article (Hydrochemistry and isotopic composition), Journal of Atmospheric Chemistry, 2005
- Megacryometeors: Scientific article (Distribution on Earth, AMBIO: A Journal of the Human Environment, 2006)
- Huge chunks of falling ice mysteriously pelt Iowa neighbourhood, smash roof
- Getting to the truth of falling ice chunks, Chemical Science, Katherine Davies, 2008
- Monitoring the fall of large atmospheric ice conglomerations: a multianalytical approach to the study of the Mejorada del Campo megacryometeor, Journal of Environmental Monitoring, 2008
- What Causes Megacryometeors?
- The problem of Ice Meteorites, Martin Beech
- Top 100 Stories of 2008 #73: Giant Ice Meteors Fall From Clear Skies, Karen Wright
This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)




