Earth’s Cryosphere, 2012, Vol. XVI, No. 4, p. 21-30
CONTEMPORARY DYNAMICS OF FROST MOUNDS AND FLAT PEATLANDS IN NORTH TAIGA OF WEST SIBERIA (ON THE EXAMPLE OF NADYM SITE)
O.E. Ponomareva, A.G. Gravis, N.M. Berdnikov
Earth Cryosphere Institute, SB RAS, 625000, Tyumen, P/O box 1230, Russia; o-ponomareva@yandex.ru
It has been proved that, despite climate warming since 70s years of XXth century, the frost heave has still been an active process in the northern taiga of West Siberia. It has been established that the frost heave here involved not only the uneven-age (including the relict ones) frost mounds and the bogs, but also the flat peatland. Features of manifestation of the frost heave in space and the interrelation between the intensity of the frost heave and the climatic parameters have been discussed. The reduction of the frost heave intensity and the thermokarst revival observed during the last 10 years due to the proceeding drowning of climate in the XXI century has been reasoned. During some favourable years with low-snow winters insignificant revival of the frost heave process and a slight surface lifting have been marked. That is why the surfaces of hillocks and peatlands have been generally kept on the marks of 10-year prescription. Thus, all the created forms of frost heave and peatlands in the northern taiga of West Siberia have been in the condition of unstable balance. At the same time the active growth of new hillocks and small ridges of frost heave in the regional parts of bogs has been revealed.
Key words: Frost heave, frost mounds, flat peatland, climate, monitoring.