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To trace the surficial responses of lowlands to past climate change, we investigated delta C-13 in total organic carbon (TOC), C/N ratios, magnetic susceptibility (MS), and silicon (Si) intensity (directly proportional to concentration) in wetland sediments collected from the Gimpo area of central Korea, covering 6600-4600 cal yr BP. Two organic layers with high TOC%, negatively depleted delta C-13(TOC) values (-27 to -29 parts per thousand), low MS values, and low Si intensities were found at 6200-5900 and 5200-4800 cal yr BP, respectively. These middle Holocene wet periods corresponded to relatively intensified summer monsoon and solar activity periods. The intervening dry period (5900-5200 cal yr BP) with high MS, high Si, and low TOC% corresponded to an intensified dust-activity interval and stronger winter monsoon. This multi-centennial climatic fluctuation of wet periods (6200-5900 cal yr BP and 5200-4800 cal yr BP) and an intervening dry period (5900-5200 cal yr BP) in central Korea was more synchronous with climate change in the arid inner part of China than with that in South China, suggesting possible strong high-latitude-driven climatic influences (e.g., North Atlantic cooling events) during the middle Holocene. (C) 2015 University of Washington. Published by Elsevier Inc. All rights reserved.