Today, nobody already denies the fact of climate global warming. What will expect us in the future? This issue is the subject of heated discussions of scientists all over the world. Different scenarios of possible consequences of the processes taking place now, including melting of permafrost, arctic ice* with rise of ocean level and flooding of fields of land (in Siberia, for example, Yamal Peninsula and some lowlands), are considered. To struggle against such disastrous phenomena, they even suggest to "throw" aerosols at near-Earth space which will stop rise of temperature of near-surface atmosphere. The opposite versions are also discussed: it is possible that within the next 7 - 10 years cooling will begin as a result of forecasted weakening of solar activity**.
This divergence of views speaks for imperfection of the existing climate theory which has been considered as a steady characteristic of one or another zone for centuries. Only in the last decades they began to regard it as a complicated dynamic system making attempts of its strict physical and mathematical description.
Warming being observed at present is determined by many events of heliosphere, geosphere, biosphere, man-made nature, and at mathematical modeling of climate it is compulsory to take them into account at the same time. When developing a theory of sensitiveness to external actions which have regional peculiarities, the analysis of empirical data becomes more topical (moreover, as to many zones of the planet, they are accumulated for a rather long period of time). The study of the regularities revealed on its basis is at the stage of methodological search for the time being.
From here particular interest of scientists in such a vast continental zone as Siberia (about 10 mln km') is clear. The analysis of instrumental data shows: frequency of abnormal deviations from climatic norms during the 20th century has not changed as a whole. However, in some areas for the last decades warming has proceeded at a more rapid pace than in other places of the planet. Director of the Institute of Climatic and Ecological Systems Monitoring of the Russian Academy of Sciences (RAS) Siberian Branch (Tomsk), corresponding member Mikhail Kabanov told the newspaper Science in Siberia about the results of study of respective processes taking place in this region now.
The study of time scales of natural and climatic changes for the last century, namely a wavelet analysis, the more efficient method of revealing their periodicity, helps understand the role of different factors in warming, including atmospheric circulation regulating inflow of warm or cold air masses. It should be noted that both expected and unexpected results were obtained with its help. The former include a steady connection of rows of annual average temperature in the West-Siberian region with Wolf numbers (characterizing solar activity). The latter include its correlation (interdependence) with the North-Atlantic oscillation (NAO) index (difference in pressure in observation points of this part of the ocean, characterizing the conditions of western transfer of air masses). Thus, a few years later after this figure changed Siberia "responds" to this phenomenon by rise of air
* See: "Icebergs: Pools of Fresh Water", Science in Russia, No. 3, 2007. - Ed.
** See: Yu. Israel, " Do Climatic Disasters Threaten Us?", Science in Russia, No. 4, 2004. - Ed.
temperature, the explanation of which should apparently be found in transfer of heat from the equatorial area to the north one via meridional ocean currents.
Of late years, experts believe that the increase in concentration of greenhouse gases in the atmosphere is the main "author" of warming being observed. However, the contribution of natural and industrial components to it remains under discussion due to lack of reliable quantitative estimates. As to the former, Siberia is, undoubtedly, of interest thanks to availability of large forest and bog ecosystems there many of which were not subject to man's impact not long ago. Bolshoye Vasyuganskoye bog (53 thous. km2) located in inter-stream area of Irtysh and Ob can serve as an example. Now domestic and foreign experts carry out disciplinary exploration here and they have already found climatically significant effects.
Above all, it is a question of a particular temperature field over the bog. According to instrumental measurements, during winter and spring the air above it is
warmer, while in summer and autumn is colder than that above adjacent areas. Such difference in temperatures (2 - 4°C) can be explained by specific heat-transfer properties of peat and bog systems. However, it is surprising that, according to satellite data, it is preserved in a high atmospheric column-up to tropopause (8 - 10 km above land surface). To understand the meaning of this fact, further accumulation of material is necessary.
Moreover, the observations have shown that emission flows of carbon dioxide coming from different bog phytocenoses (high, low forest stand, open bog) on peat deposits of 3 - 5 thous. years old can differ by two and more times. Therefore, for the purposes of credible quantitative assessment of the balance of greenhouse gases above the whole area under consideration, they started to carry out its detailed landscape mapping. Meanwhile, statistical data processing with relation to one of the areas allowed to make the following conclusion: one of the key parameters of this range is temperature of ground air (one can state with acceptable accuracy: the higher it is, the more intensive is outburst of carbon dioxide). In the light of warming being observed the study of bogs located to the north from Vasyuganskoye bog becomes more topical. There cryogenic processes and active outburst of methane play an additional and still little studied role in the increase of content of greenhouse gases in the atmosphere.
The results of the Siberian scientists' works obtained to date confirm correctness of the approach to the study of climatic changes which was chosen by them as early as the beginning of the 1990s (now it became universally acknowledged), i.e. through their description for individual regions. It is not by accident that the Integrated Regional Researches have become the priority direction of the International Geosphere and Biosphere Program since 2002. Further plans of experts of the RAS Siberian Branch include implementation of the "basic" project "Integrated researches of natural and climatic changes and risks of nature use in Siberia related to them" envisaging inter-disciplinary study of relevant processes by widely using the latest methods and technologies of land and aerospace monitoring.
Kabanov M., The Modern Climatic Changes in Siberia, "Science in Siberia", No. 12, 2007
About · News · For Advertisers · Donate to Libmonster
Libmonster ® All rights reserved.
2014-2023, LIBMONSTER.COM is a part of Libmonster, international library network (open map)
Keeping the heritage of the United States