Satellite Monitoring of Siberian Wetlands in the Climate and Social Context
Zakharova, Elena1; Kouraev, Alexei2; Kirpotin, Sergey3

Zakharova E.A.1,2, Kouraev A.V.3,2, Kirpotin S.N4

1) CNRS; LEGOS, F-31400 Toulouse, France
2) State Oceanography Institute, St. Petersburg branch, Russia
3) Universite de Toulouse; UPS (OMP-PCA), LEGOS, F-31400 Toulouse, France
4) Tomsk State University, Tomsk, Russia

One of the specific features of the Siberia is the presence of largely developed wetlands - bogs, lakes and floodplain fens. These wet zones substantially change the vertical water and heat exchange in the atmospheric boundary layer as well as affect and transform the runoff regime. The water storage of wetlands is the result of water balance and, similar to arid zones, is expected to vary with climate change.

We use active and passive satellite observations in the microwave (TOPEX/Poseidon, ENVISAT, SMOS, SSM/I) and visible range (MODIS, Landsat) in combination with in situ data and hydrological numerical modelling to estimate time and space variability of various hydrological parameters (lakes and wetlands extent, water level, snow cover, runoff etc) of the Siberian wetlands. We then make an attempt to understand the climate-wetlands-society interconnections and feedbacks.

In the northern part of the Western Siberia (region affected by permafrost) we observe since 1990s an increase of meltwater loss in wetlands. Among the possible reasons are wetlands extension, permafrost melt or human impact. Many thermokarst lakes (arctic ponds) in this region dry out, and it is still not clear in what degree it is related to climate change and/or human activity, and what are the mechanisms - subsurface infiltration or surface drainage. There is also a significant difference in evolution of thermokarst lake complexes between Western Siberia and more arid Central Siberia.

We demonstrate how changes in water regime of wetlands in the warming climate impact human society. Later soil freezing in Western Siberia and increasing wetness of thermokarst lake complexes in semi-arid Central Siberia can have both positive and negative effects on economical activity (herding, agriculture, transport etc).

This research has been done in the framework of the Russian-French cooperation GDRI "CAR-WET-SIB" and "Franco-Siberian Center for Research and Education", French ANR "CLASSIQUE", PNTS "Permafrost" and CNES TOSCA SWOT projects, Russian FZP 1.5 and EU FP7 MONARCH-A projects.