Mr. MENG Bowen Department of Earth Sciences, HKU
Inland Asia, an arid/semi-arid region with limited water resources and fragile ecological system, is sensitive to climate change. Different from monsoonal area, moisture in inland Asia was transported by the westerlies far from the North Atlantic region. How global climate change impacts this region, in particular hydrological conditions, largely remains uncertain. The instrumental data can only cover a few decades, not sufficiently long to address natural climate variability. To this end, lake sediments from many lakes in this region are ideal archives to investigate past climatic changes over longer timescales. Although numerous studies have been conducted in this region, those studies typically suffer from two shortcomings, the uncertainty in 14C chronology and the reliability of proxies used. Particularly, paleolimnological studies of Holocene climate in this region is now hindered by 1) lake reservoir effect 2) scarcity of records indicating migration of its boundary with monsoon area and 3) lack of continuous terrestrial temperature record during the Holocene. In my proposed study, I will analyze selected lake sediment cores to address the following issues: what is the downcore variation of lake reservoir effect, did the boundary between westerlies and monsoon migrate with climate change and how did the climate change over the Holocene?