Newsgroup: it.cultura.filosofia
Titolo: aljazeera: EL Niño alterazioni nel clima globale [By  Steff Gaulter][una preghiera per la pioggia?]

http://english.aljazeera.net/focus/2009/07/200972963758331498.html
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cit on
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The waters of the Pacific are moving and in Australia farmers are
getting nervous.
El Ni�o, the natural phenomenon known to bring turmoil to global weather
patterns, is back.
Over the last couple of months the waters of the Pacific have shifted
and the first impacts are already being seen.
 
During a 'normal' year, the prevailing winds push the warm surface
waters of the Pacific toward Indonesia. This makes the waters there
about 8�C warmer and half a metre higher than the waters along the west
coast of South America.
 
During El Ni�o, the winds ease and this allows warmer waters to well up
along the west coast of South America, around Peru and Ecuador.
 
The change is tiny, just a couple of degrees Celsius, but it has a
dramatic affect.
Livelihoods destroyed
 
The fish that prefer colder waters are no longer found off the coast of
Peru or Ecuador, but instead swim thousands of miles further north or
south.
This can devastate the livelihood of the fishermen and severely damage
economies: The demise of the Peruvian anchovy industry is largely blamed
on the El Ni�o event of the early 1970s.
 
The warmer waters can also well up near the coast of California,
disrupting existing marine life there.
During El Ni�o, an increase in the number of malnourished sea lions has
been noticed, as their favourite foods such as squid, anchovies, herring
and sardines, disappear in search of colder waters.
This year the Marine Mammal Centre in Sausalito, California, has already
noticed an increase in the number of sea lions it has rescued.
In the past, the effects of El Ni�o have been observed on marine life as
far away as Antarctica, but it is not just the sea life that suffers.
Drought
Fishermen's livelihoods can be devastated as fish swim further away
[GALLO/GETTY]
The warmer waters of the Pacific generate showers, which usually fall
across Indonesia.
As the waters head east, so do the showers. Indonesia sees drier weather
and the rains over the coast of Peru or Bolivia become heavier. Over the
last month or so there has been a decrease in the rainfall over
Indonesia.
 
The effects are expected to become even more widespread in the coming
period between December and February.
The dry conditions over Indonesia are forecast to spread, with much of
southeast Asia and northern Australia drying out. The last thing
Australia needs is another drought.
Certain other places, however, can expect things to get a lot wetter.
California is one of the places that often sees flooding during El Ni�o
events. Northern Argentina, Uruguay, Southern Brazil and Paraguay are in
the firing line too, and Uganda, Kenya, southern Sudan and southern
Ethiopia are also likely candidates.
But it is not all a disaster - El Ni�o events usually bring milder
winters to Japan and Canada, and they reduce the risk of hurricanes.
This global weather phenomenon also indirectly disrupts the vertical
development of storms in the Atlantic which should mean a quiet
hurricane season.
Unpredictable
An El Ni�o is a completely natural event that usually lasts between a
year and 18 months. It rears its head every two to seven years, with
varying degrees of vigour.
We know that they have been occurring for thousands of years, but their
global affects were not recognised until the 1900s.
To this day, they are still not fully understood.
Obviously this means that forecasting their affect is going to be nigh
on impossible. Even forecasting the actual El Ni�o itself is not easy;
it is difficult to say when an El Ni�o event is going to occur and
equally difficult to say how strong an event is going to be.
As if to prove the point, current forecasts cannot agree on the strength
of this latest El Ni�o event.
Mike Halpert, the deputy director of the Climate Prediction Centre at
The National Oceanic and Atmospheric Administration (NOAA), says: "The
most recent dynamical (model) forecasts have come in a bit stronger,
with the large majority of them forecasting a moderate to even strong
event.
"Right now, it is hard to imagine this event rivalling the very strong
events of 1982/83 and 1997/98."
 
The stronger the event, the larger the change in temperature across the
Pacific, and the larger the bearing it has on the weather across the
globe. However, none of these droughts or floods can ever be guaranteed.
We may see all of these disasters, but then again we may see none.
Steff Gaulter is Al Jazeera's senior weather presenter.
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cit off
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http://it.babelfish.yahoo.com/

 We may see all of these disasters, but then again we may see none.
In other words they are just guessing and don't really know what the
hell they are talking about, sad is that it's costing us money that
could be used for better purposes.