El Niño warmed globally

July 2, 2013. Thanks dendrochronological analysis, and measurement of the radiation balance of the Earth's surface after the eruption of volcanoes Chinese scientists can say with confidence that the unusual activity of the El Niño phenomenon is a result of global warming. Another group of researchers suggested that climate model, which can be used to predict the next period of activity of the natural anomalies.

El Nino — a natural phenomenon, often accompanied by numerous victims, causing epidemic disease and even provoking armed conflict. The essence of the climate anomaly is this: the El Niño Southern Oscillation, or — phase temperature fluctuations in surface waters of the equatorial Pacific Ocean, has a significant impact on the climate.

The heated water is moving east, warm tropical pool spreads, and the vast Pacific Ocean is an increase in water temperature. As a result of the deep ocean waters, rich in nutrients, no longer rise to the surface, the fish die from lack of food. Winds bring moist air masses, because of this, Peru and Ecuador happen downpours and flooding. In Central America, Indonesia and parts of Australia, the reverse process: the weather turns warm and dry, with frequent droughts and forest fires.

Extreme weather conditions pose an increased risk of the spread of epidemic diseases such as malaria, dengue fever and Rift Valley fever. There is also a suggestion that poor harvests caused by El Nino, increase the risk of civil war: the study of data from 1950 to 2004 showed that El Niño is associated with 21% of all civil conflicts of the period.

See also: El Niño brings war

At the end of the twentieth century have been reported particularly strong El Niño. However, the researchers did not have data on the activity of the previous climate anomaly to say with certainty whether such activity is natural or caused by human factors.

Researchers Do Tszinbao from University of Hong Kong and Xie Shanpin from Scripps Institution of Oceanography have shown that increased activity of the El Niño phenomenon in the late twentieth century is related to global warming. The results of their research can be found in the journal Nature Climate Change.

The researchers studied 2,222 cut trees Polylepis tarapacana, growing in South America on the plateau Altiplano. These plants are very sensitive to climate changes caused Southern Oscillation. The scientists compared the data from the last 700 years, resulting dendrochronological analysis. Later, these results were compared with the information obtained with the help of modern technology.

These eloquently that the activity of El Niño in the late twentieth century did more than all the previous records.

But can we relate this to the influence of human activity on the climate? Li and Xie Tszinbao Shanpin say that after major volcanic eruptions, tropical waters east-central Pacific are unusually cold, but a year later there comes warming. As well as greenhouse gases, volcanic evaporation violate the radiation balance of the Earth.

This is indicative of the fact that an unusually high activity of El Nino in the late twentieth century may be a consequence of global warming.

 

Blue line — the data obtained by the annual rings. Red line — the results obtained appliances. The dotted line — the boundary of natural fluctuations of El Niño activity.

Do Tszinbao said "the Newspaper", "Based on our research of tree rings and statistical tests, we can with high confidence that El Niño activity is likely to depend on global warming. I prefer to say "most likely" and not "clearly", as in science there is always an element of uncertainty. However, we still can not accurately predict what will be the activity of El Niño over a specific period of time in a particular region: it needs to build a more accurate climate models. The results obtained will help to improve the accuracy of these models and their predictions. And in any case, we now know that if the global warming trend of increasing activity of the El Niño continues, we should expect more of these weather events such as floods and droughts. "

See also: 2013 will do without El Niño and La Niña

Meanwhile, a group of scientists from Germany, Russia, Israel and the United States proposed a model with which to accurately predict the manifestation of the activity of the El Niño. To do this, the researchers compared intervals that pass between changes in climate data at the control points on the surface of the Pacific Ocean. Some points are located directly in the pool El Niño, the other — in the rest of the ocean. Immediately prior to the emergence of El Niño activity interference points increases, while passing phase — is weakening. These studies are presented in a scientific journal PNAS.

Scientists argue that despite the fact that the model used by only one variable — the atmospheric temperature, their prediction method is superior to all existing at the moment. Taken as a basis for his only accurate data that allows a prognosis for the year ahead.

Source: Gazeta.ru,

Like this post? Please share to your friends: