Sharp fluctuations in climate warming is likely to point to the world: the ancient El Niño clue to future floods

Science (15 July 2011) — According to the scientists' predictions, as warming around the world, harsh climatic fluctuations caused by the floods in Pakistan last year and in Australia this year, probably will continue to be the case.

Researchers from the universities of Oxford and Leeds have found that El Niño (Born El Nino / La Nina — Southern Oscillation, ENSO) — the temperature variation of the surface water in the equatorial Pacific Ocean, which has a significant impact on the climate — annotated. Interpreter) That has an influence on the warmest water of the planet from the West Pacific Ocean to its east every 2-7 years, remains constant since the last time a very warm period of Earth-Pliocene.

The results of their study suggest that fluctuations in climate between the two "extremes", known as — El Niño and La Niña in a warmer past our planet may have occurred more frequently in the future, their frequency may increase. Extreme values of the El Niño causes droughts, forest fires, floods in most parts of the world, as well as a negative impact on the fisheries.

Doing a report in the journal "Paleookeanografiya" team of geochemists and climate scientists have used Pliocene as an analogue of the past and predictor of the future climate of the Earth.

Pliocene (it lasted from 5 to 3 million years ago) was characterized by the same level of carbon dioxide, as now, its average global temperatures by 2-3 degrees higher, so it is suitable as a basis for testing in climate research.

Lead scientist Nick Skrokston of Oxford University with the Faculty of Earth Sciences said: "We know from previous studies that the mean state of the Pacific during the warm Pliocene was similar to the climate models, observed during a typical El Niño, which we see today.

However, until recently, there was a view that the warmer waters of the Pacific reduce climate fluctuations that were the cause of sudden weather changes at all, "subordinated" El Niño region. What we did not expect, it's the fact that climate variability will remain strong under the influence of the warmer conditions. "

The team has combined experiments conducted Hedlinskim Centre climate model to the analysis of the chemical composition of a large number of individual shells in the form of the simplest organisms known as foraminifera (Foraminifera (Latin Foraminifera) — detachment of the simplest subclass rhizopods form deposits of lime and silicic rocks — annotated. Interpreter).

They collected them in the form of sediment from the bottom of the equatorial eastern Pacific and received information about the temperature of the upper layers of the ocean at all times. They concluded that the range of temperatures to which the organisms have undergone during the Pliocene, was higher than those expected in the seasonal cycle.

Separate temperature change can be explained by the additional temperature fluctuations caused by system El-Nino/La-Ninya.
The authors say that the coincidence of the conclusions of the data from the ocean floor and simulation allow some to doubt that ENSO will continue to exist in a warmer world. Earlier this year, a team from Japan studying corals for the same period showed that the climate variability in the western Pacific Ocean is similar to today's state of affairs, thus exposing the idea of a permanent El Niño during the Pliocene.

Moreover, this new research shows that the temperature fluctuations of the Pacific Ocean may be caused by El-Nino/La-Ninya. It is assumed that our warmer future, be of a stable and regular, that is a recipe for extreme climate events.

Translation: Anna Krasnov
Source: Science Daily

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