El Nio, the warm ocean current in the South Pacific can do the incredible, it can slow down the rotation of the Earth
A LITTLE child can slow down the Earth’s rotation and the little devil is none other than El Niño. As a result the days are getting a little longer — and it’s not just because of the summer season. Researchers gathered in Boston for a meeting of the American Geophysical Union were unanimous — El Niño the ocean current in the South Pacific — was slowing the Earth’s rotation by almost a thousandth of a second.
‘The energy is going from the Earth into the atmosphere causing it to slow down,’ says John Gipson a scientist with the National Aeronautics and Space Administration’s (NASA) Goddard Space Flight Centre. According to NASA estimates by July 1997, El Niño had slowed down the Earth’s rotation by 800 microseconds. Throughout the El Niño phenomenon, which is expected to taper off in August 1998, the Earth’s rotation has slowed by an average of 300 to 400 microseconds. However it seems the Earth is all set to make up for most of this loss of time. A cold counter current which emerges after the warm ocean current — which El Niño is — speeds up the Earth and makes days shorter. This current is called La Niña.
‘Following the current El Niño, we will be going through one of those periods where the Earth speeds up and makes the days shorter,’ says Gipson said. This is not the first time an El Niño has made the days longer. The 1982-83 El Niño also slowed down the Earth’s rotation, though to a lesser degree, scientists say. During an El Niño, the ocean temperature is raised in the eastern Pacific and reduced in the western Pacific. The phenomenon, is responsible for floods in Ecuador, drought in Indonesia and ice storms in Quebec and the US northeast. It changes the ocean currents and the intensity and direction of atmospheric winds. This large scale shift in winds and currents changes the length of day by a fraction of a second, which can only be measured by satellites in outer space.
The change in wind direction and speed makes the atmosphere act as a huge blanket trying to obstruct the rotation of the Earth. Since the atmosphere acts as a drag it manages to reduce the speed of rotation. At the same time the energy of the movement is converted into heat and released into the atmosphere adding to the El Niño effect. Therefore the breaking action serves two purposes, it increases temperature and it slows down rotation. But this does not last forever. La Niña is the opposite phenomenon to El Niño. While water temperatures in the western Pacific rise the eastern Pacific gets colder. It too affects the planet’s rotation causing it to speed up, but only about 75 per cent as much as El Niño slowed it down. Jean Dickey of NASA’s Jet Propulsion Laboratory said that while the common person would probably not be affected by such a small shift in the Earth’s rotation, ‘it plays a very important role in inter-planetary navigation.
It was for example a critical factor in the success of the Pathfinder mission to Mars. University of Texas at Austin Professor Byron Tapley added the speed of the Earth’s rotation was also key to the functioning of the Global Positioning System (GPS) used by ships, planes and the military. El Niño, which is known as the Christ child or little one is more of an anti-christ. It destroys the marine foodchain leading to the starvation deaths of thousands of smaller organisms and consequently the larger ones that depend upon them for survival. It also leads to devastating storms and showers in regions where it doesn’t rain for years at a stretch. In regions of plentiful rainfall it can lead to a drought. El Niño .is also responsible for the recent outbreaks of infectious diseases through South America, Southeast Asia and Africa, says a study of the World Health Organisation.
This weather phenomenon has caused rapid spread of several diseases such as malaria, rift valley fever, cholera and a form of dysentery, known as shigellosis through the three continents in last few years, it says. There is close association between it and the upsurge of cholera in Africa which has claimed 4,070 lives and affected another 81,636 individuals since last year. The cholera epidemic has also been raging in South American countries like Peru, Honduras and Nicaragua for the past seven years. .El Niño is a phenomenon that occurs once in a decade.
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