A^-1 annual) can be used as a peculiar criterion of amplification of a climatic signal.

The calculations indicated that regions with the maximum CI values were located in the layer 200-300 m at the depth of the Atlantic water. Horizontal CI distribution at 300 m presented in Fig. 6 illustrates that zones of the maximum CI values are predominantly located in the continental slope domain and over the ridges of Mendeleyev and Lomonosov.

The CI values can be as high as 3-4 units in the regions over the Siberian continental shelf. It is apparent that these regions are the most representative ones for study of climatic variations in the Arctic Ocean. Therefore, we shall use observation data for different years collected at the continental slope of the Laptev and East Siberian Seas in order to reveal trends of climatic variability of the thermohaline structure.

The interannual temperature variability in the kernel of the Atlantic waters in two points located in the region of the continental slope in the Laptev and East Siberian Seas is shown in Fig. 7. Temperature increase of the Atlantic waters From the end of the 70-s with maximum in the middle of the 90.s is clearly pronounced. It supports the conclusions about the reconstruction of the thermohaline structure in the end of 70-s (Pavlov and Stanovoy, 1997; Alekseev et al., 1997).

4. CONCLUSIONS

　

The T, S-structure and the heat transfer from the Atlantic waters to the surface is significantly influenced , along with the well-known mechanisms (the vertical convection and internal wave destruction), by the upwelling in the cyclonic eddies appearing over the continental slope.

The continental slope regions are some kind of peculiar natural amplifiers of the long-term signals and key objects for performance of climatic monitoring of the thermohaline conditions of the Arctic Ocean.

　

Analysis of variability of thermohaline structure in the region of the continental slope of the Laptev and East-Siberian Seas indicates the increase of the temperature of the Atlantic waters from the end of the 70-s.

　

5. REFERENCES

　

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Alekseev, G.V., L.V. Bulatov, V.F. Zakharov and V.V. Ivanov, 1997: Incoming of unusual warm Atlantic water to Arctic Ocean, Doklady RAN, v.356, No 3,401-403 (In Russian).

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Pavlov, V. K., 1995 : Modeling of the thermohaline water circulation of the Arctic 0cean. Extended abstract of poster resented at the Arctic Nuclear Waste Assessment Program Workshop, Woods Hole, Massachusetts, May 1-4, 1995.

Pavlov, V.K. and V.V. Stanovoy, 1997: Climatic signal in the fluctuations of the sea level and river run-off in the Arctic Ocean. Proc. 0f Conf. Polar Processes and Global Climate, P.2, Rosario, USA, 1997, 184-186.

Pavlov, V.K. and P.V. Pavlov, 1998: Features of seasonal and interannual variability of the level regime and water circulation in the Laptev Sea. In: Land-ocean systems in the Siberian Arctic: Dynamics and History (in press ).

Polyakov, I.V. and L.A. Timokhov, 1994: Mean fields of the temperature and salinity of the Arctic Ocean, Meteorologia i geolrologia, No 7,68-74 (in Russian).

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Rhines, P.B., 1970: Edge-, bottom-, and Rossby waves in a rotating stratified fluid, Geophys. Fluid Dyn., v 1, pp. 273-302.

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Shpaikher, A.O., 1967: About the Atlantic water influence to the formation of the hydrometeorological processes features in the wintertime, Izv. VGO, vol.99, No 2, 114-121 (in Russian).

Terms and notions, 1980: Terms and notions. Informational Tables (ed. Gorshkov S.G.), M., GUNI0 MO SSSR, -156 p.( in Russian).

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