SGER: Formation Time and Past Changes in the Atmospheric Circulation System over Northwest Mongolia--A Pilot Study of Lake Hovsgol Sedimentary Proxy Records

该奖项在探索性研究小额赠款（SGER）项目的支持下，将分析从蒙古最大的水体-呼斯古尔湖收集的沉积物岩心，以确定其是否适合进行详细的古气候调查。研究人员希望检验这样一种假设，即全新世时期的大气环流正在经历周期性的波动，这种波动能够导致该地区的显著变化。蒙古西北部的干旱和荒漠化导致了该地区的干旱和荒漠化，目前蒙古75%的人口居住在该地区。 Hovsgol湖的水量收支在很大程度上取决于区域降水模式，它位于西伯利亚高压和潮湿西风带下方，是研究大气环流大规模变化的理想位置。然而，目前尚不清楚所回收的岩心质量是否足以回答任何提出的科学问题。 因此，这项研究将解决以下三个基本问题：新发现的库苏古尔湖岩心的年龄跨度是多少？湖相沉积和生产力的哪些指标可能对指示区域气候变化最有用？亚洲大陆内部的呼苏格湖地区的现今气候系统是什么时候建立起来的？它随时间的变化有多大？这些基本信息将对了解蒙古西北部从末次盛冰期到全新世的气候变化产生广泛的影响。

This award, under the auspices of the Small Grants for Exploratory Research (SGER) program, will analyze select sediment cores collected from Mongolia's largest water body, Lake Hovsgol, to determine their suitability for detailed paleoclimatic investigations.Ultimately, the researchers want to test the hypothesis that atmospheric circulation during the Holocene period was undergoing periodic fluctuations capable of causing pronounced changes in the regional precipitation regime in northwest Mongolia leading to droughts and desertification in the area where 75% of present-day population of Mongolia now resides. Lake Hovsgol, whose water budget is strongly dependent on the regional precipitation pattern, is ideally located to examine large-scale changes in atmospheric circulation as it lies beneath the Siberian High and the moisture-bearing westerlies.At this point in time, however, it is not clear if the recovered cores are of sufficient quality to answer any of the posed science questions. So, the research will address the following three basic questions:What is the age span of the new recovered Lake Hovsgol cores?What proxies of lacustrine sedimentation and productivity might be most useful to indicate regional climate changes?When did the present-day climatic system in the Lake Hovsgol area of continental interior Asia become established and how variable was it through time?This basic information will have broad impact in providing an understanding of climate variability in northwest Mongolia from the Last Glacial Maximum through the Holocene.