What climate changes does Antarctica predict?


MOSCOW. (Nikolai Osokin for RIA Novosti) - Not long ago, I came back from Antarctica where I stayed with the 52nd Russian Antarctic expedition. This continent is unique - it has no state borders and scientists can choose to work wherever they want.

This freedom is granted by the Antarctic Treaty signed on December 1, 1959. It designates Antarctica as a "natural reserve, devoted to peace and science." Every country has the right to conduct research there. Russia has five out of some 50 research centers belonging to 20 states.

Antarctica is attracting researchers because the processes taking place in its air, ice and the surrounding oceans determine the global climate. Moreover, being the most removed from industrial centers, this continent is an indicator of the global changes in the air, water and ice.

Antarctic studies are helping researchers to learn about the past and predict the future. As any other glacier, Antarctica's ice coat formed from snow that piled up, turning eventually into ice. This process continued for hundreds of thousands of years. Annual ice layers are telling us about all past winters because every snow flake remembers how it was born.

A glacier is a vertical record of information. Antarctica is a unique storage of information about the climate's global change over hundreds of thousands of years.

Antarctica contains 90% of the world's ice on its area of 12 million square kilometers. Its ice cover is also the world's biggest fresh water reserve with 24 million cubic kilometers of ice. In addition, Antarctica has big reserves of mineral reserves and colossal amounts of biological species in its waters.

Researches are studying Antarctica to understand its past and future changes and evaluate their influence on the climate's global fluctuations. At the Vostok station in central Antarctica, Russian researchers have drilled 3.5 km of ice for the first time to receive a specimen with information on ice accumulation in the last 400 thousand years. An analysis of this specimen has revealed that during this period the Earth saw four two-phase climatic cycles - gradual warming and quick cooling. We are now at the peak of warming that should give way to another cooling.

For the time being, everyone is worried about the global warming, all the more so as ice is melting before our eyes, threatening many maritime cities and whole countries. The ice cover of the Arctic Ocean is disappearing together with most alpine glaciers. But since almost all of the world's ice is in Antarctica, it has a decisive influence on the level of the world's oceans.

How does Antarctica behave today? Observations at the Bellingshausen station near the Antarctic peninsular have registered steady increase in temperatures (particularly in summers) over the last 30 years of the 20th century - from one to one and a half grades. But in the beginning of the 21st century, the trend has reversed and the average annual temperatures, especially in summer, have been going down.

I have found out on the Antarctic peninsular (Western Antarctica) that the situation with glaciers is different. In some places, they are retreating, but in many places they are stable and even on the onslaught. Glaciers are not melting quickly even in Antarctica's warmest area. But the bulk of ice is in Antarctica's cooler eastern regions, which means that the situation is pretty safe.

The Russian Vostok station located in central Antarctica - the world's Pole of Cold (the minimal temperature - 88.3° C) - has not registered any significant changes in average annual temperatures over 50 years of observations. It rose from -55.7° C in the early 1960s to -55.2° C in the middle 1980s, but went down by one tenth of a grade (to -55.3° C) in the beginning of the 21st century.

On the edge of Eastern Antarctica, where the Mirny station is located, the average annual air temperatures have practically remained the same since the 1950s. Another Russian station - Novolazarevskaya - has recorded a temperature increase of one grade C from the early 1960s to the early 1990s, and a decrease in the past few years.

These observations show that the Antarctic air temperature has not been going up. Hence, the Antarctic ice is not likely to be melting faster, and the level of the world's oceans will not change much.

Nikolai Osokin works at the Geography Institute of the Russian Academy of Sciences.

The opinions expressed in this article are the author's and do not necessarily represent those of RIA Novosti.

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