Global Change Observatory Central Asia (GCO-CA) – Palaeoclimate, Environment, and Climate Change
Central Asia, extending between the Caucasus and the eastern Tibetan Plateau, with a semiarid/arid belt with water shortage to the west and a glaciered mountainous area with very unstable surface conditions to the east, holds a key position for understanding geodynamic and climate processes. Given the climatic and topographic features, Central Asia provides a natural laboratory to monitor risk scenarios related to water excess and shortage, and high seismicity. This initiative aims to investigate cause-effect-relations of landscape evolution at different spatial and temporal scales using ground and space based monitoring systems.
Within the frame of the GFZ focus-project GCO-CA scientists from section 5.2 are investigating particularly the dynamics of climate and environment of the region. We must turn to palaeo-records for a wider spectrum of climate variability, environmental changes, and natural hazards because there is no modern analogue situation for the predicted climate change and the magnitude and recurring frequency of disastrous events as earth quakes, landslides, lake outbreaks and floods. The complexity evidences that scientific networking between different disciplines will be mandatory.
Currently investigations are focused on sites in the Kyrgyz Republic, with support from Central Institute of Applied Geosciences (CAIAG) in Bishkek. In future partners from other countries as Tajikistan, Kazakhstan, and China will be involved. At the moment we have cooperation with partners from the Kyrgyz-Russian Slavic University Bishkek, the Kyrgyz National Agrarian University Bishkek, and the Russian Academy of Sciences Bishkek. Different German groups (from Free University Berlin, Technical University Braunschweig, Friedrich-Schiller-University Jena, Senckenberg Research Station for Quaternary Palynology Weimar) are involved via the BMBF-funded project Central Asian Climate Dynamics (CADY).
Sites of the Kyrgyz Republic currently under investigation in section 5.2
Investigations of lake sediments and limno-monitoring
Investigations of lake sediments and limno-monitoring is focused currently on two shallow, large lakes of intramontane basins (Lake Son Kol at 3061 m NN, and Lake Chatyr Kol, at 3520 m NN), and one deep lake build behind a natural dam from an avalanche (Sary Chelek, at 1873 m NN).
Kyrgyz caves as high-resolution archives of palaeoclimate and seismicity
Speleothems from caves form excellent archives of paleoclimatology and -hydrology. They can be accurately dated with U-Th technique back to 500.000 yrs.
GCO-CA Tree-ring Research
Tree-ring features of Central Asian long-lived tree species like juniper (1600yr old trees already found), spruce (ca. 300yrs) and fir (ca. 700yrs) provide annually resolved information on past climate dynamics and can be likewise used for dating palaeoseismic events.
Dust monitoring at the Northern slope of Tien Shan
In the frame of a joint project with the Central Asian Institute of Applied Geosciences CAIAG, the Russian Academy of Sciences, and the Slavonic University Bishkek a dust monitoring station was installed on the territory of the Russian Academy’s research station 40 km south of Bishkek at an altitude of 1,750 m a.s.l.. Meteorological parameters and particle concentrations in the atmosphere are continuously measured for 30 grain size classes.