This book examines relationships between climate-hydrological changes and other phenomena including land use and natural disasters during the Holocene and recent past. In particular, periods of rapid climatic shifts such as global warming and global cooling are examined through paleohydrological and other studies of various lake-catchment systems in East Asia, from Mongolia in the north to Taiwan in the south. A number of different research techniques are used in the work presented here, including sediment analysis and optically stimulated luminescence dating and the reader learns how the lake-catchment system functions as a "proxy observatory" for past and present environmental monitoring. The lake catchments studied by the authors of this volume are under similar climatic conditions, i.e., under the East Asia monsoon, with some systematic difference in climatic factors. Both proxy and observation data are available for the surrounding countries' provisions against natural disasters that are related to climate-hydrological events and readers will see how present instrumental observation data can be connected to past proxy data (sediment information) in the system.