La Nina is the term we often hear, particularly those related to climate and weather around us. The term is derived from Spanish meaning "little girl" is a condition in which a decline in sea surface temperatures in the eastern equator in the Pacific Ocean. La Nina can not be seen physically, the period was not fixed.
In the event of La Nina, trade winds blowing along the eastern Pacific Ocean rose (Walker Circulation shifts toward Bafat) so that the mass of warm water carried by more and more toward the western Pacific. As a result, the mass of cold water in the eastern Pacific moves to the top and replace the warm water mass that moves them. This is commonly called up-Welling. With the change of water mass that is, sea surface temperature decreased from normal values. La Nina usually occurs in winter in the northern hemisphere the equator.
In the event of La Nina, trade winds blowing along the eastern Pacific Ocean rose (Walker Circulation shifts toward Bafat) so that the mass of warm water carried by more and more toward the western Pacific. As a result, the mass of cold water in the eastern Pacific moves to the top and replace the warm water mass that moves them. This is commonly called up-Welling. With the change of water mass that is, sea surface temperature decreased from normal values. La Nina usually occurs in winter in the northern hemisphere the equator.
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| La Nina conditions emerge as a tongue of cold water (purple) in the eastern Pacific. (Picture from: http://www.bbc.co.uk/) |
Apparently, not only related to La Nina weather happenings as well as its impact on the physical environment. Recent research suggests, La Nina is likely to be one of the triggers of pandemic flu. A number of scientists in the United States found that four of the last pandemic occurred after a wave of cold La Nina, which brings cold water to the surface in the eastern Pacific.
In the journal Proceedings of the National Academy of Sciences (PNAS), they write. carriers of bird flu that may alter the pattern of migration when La Nina occurs. However, the researchers add, there are also many instances when La Nina occurs without the spread of new flu strain in the world. Thus, although the phenomenon of climate is one trigger a pandemic, it is not the only factor.
La Nina is the cousin of El Nino heat wave (literally meaning "boy") and both form what is called the El Nino Southern Oscillation (SO-EN). "Enso confirmed - affecting weather, precipitation, and humidity around the world. However, its impact varies or does not remain in the whole world, so there is no clear picture, "said Jeffrey Shaman from Columbia University School of Public Health, USA.
Only in a research note that guided Shaman, seemed proof that the last four of the Spanish flu pandemic that began in 1918, Asian flu in 1957, the Hong Kong flu in 1958, and 2009 and then swine flu, all preceded by a period of La Nina conditions.
In the journal Proceedings of the National Academy of Sciences (PNAS), they write. carriers of bird flu that may alter the pattern of migration when La Nina occurs. However, the researchers add, there are also many instances when La Nina occurs without the spread of new flu strain in the world. Thus, although the phenomenon of climate is one trigger a pandemic, it is not the only factor.
La Nina is the cousin of El Nino heat wave (literally meaning "boy") and both form what is called the El Nino Southern Oscillation (SO-EN). "Enso confirmed - affecting weather, precipitation, and humidity around the world. However, its impact varies or does not remain in the whole world, so there is no clear picture, "said Jeffrey Shaman from Columbia University School of Public Health, USA.
Only in a research note that guided Shaman, seemed proof that the last four of the Spanish flu pandemic that began in 1918, Asian flu in 1957, the Hong Kong flu in 1958, and 2009 and then swine flu, all preceded by a period of La Nina conditions.
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| A new study indicates that La Niña weather effects could change the flight patterns of migratory birds — possibly triggering flu pandemics. (Picture from: http://ecocentric.blogs.time.com/) |
"If we look at the fourth event, we saw it all began immediately after the La Nina occurs in the Pacific. All of a pandemic have in common is the emergence of new viral strains that have not found a cure," he said.
The new virus is usually formed when two existing viruses infecting animals such as birds or pigs and exchanging genetic material. Linkages to the La Nina flu outbreak is not yet entirely clear, but studies have found a wild bird migration patterns and their different stopover when El Nino and La Nina occurs.
"Our best guess is the birds that normally never meet, or stop flying together when La Nina and the viruses they carry a genetic change," said Professor Shaman.
If the swine flu pandemic of 2009-2010 was part of this pattern, confirmed the virus crosses associated with birds and pigs. Wild birds sometimes perch farm in place for farm animals such as ducks or chickens coexist with pigs, especially in developing countries so that this theory was considered quite strong.
Professor Shaman warns that the chain link is not yet strong enough to be proof of a bird flu pandemic pattern as a result of weather or climate anomalies. However, he adds monitoring of birds, pigs, humans, and the genetics of influenza viruses have all been upgraded in response to recent outbreaks, both from swine flu and bird flu. He said, still needed time to demonstrate his theory is true.
"Now we can look at viral gene flow in a number of birds, pigs, and humans, and we may be able to get something more powerful than just statistical data, to obtain better evidence of a mechanism," he said. *** [LIA YULIANI | BBC | NATURE | LIVESCIENCE | PIKIRAN RAKYAT 02022012]
The new virus is usually formed when two existing viruses infecting animals such as birds or pigs and exchanging genetic material. Linkages to the La Nina flu outbreak is not yet entirely clear, but studies have found a wild bird migration patterns and their different stopover when El Nino and La Nina occurs.
"Our best guess is the birds that normally never meet, or stop flying together when La Nina and the viruses they carry a genetic change," said Professor Shaman.
If the swine flu pandemic of 2009-2010 was part of this pattern, confirmed the virus crosses associated with birds and pigs. Wild birds sometimes perch farm in place for farm animals such as ducks or chickens coexist with pigs, especially in developing countries so that this theory was considered quite strong.
Professor Shaman warns that the chain link is not yet strong enough to be proof of a bird flu pandemic pattern as a result of weather or climate anomalies. However, he adds monitoring of birds, pigs, humans, and the genetics of influenza viruses have all been upgraded in response to recent outbreaks, both from swine flu and bird flu. He said, still needed time to demonstrate his theory is true.
"Now we can look at viral gene flow in a number of birds, pigs, and humans, and we may be able to get something more powerful than just statistical data, to obtain better evidence of a mechanism," he said. *** [LIA YULIANI | BBC | NATURE | LIVESCIENCE | PIKIRAN RAKYAT 02022012]
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