Late Quaternary environmental and climatic changes in the eastern North Pacific

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Understanding of mechanisms behind climate change, and its influence on Earth's ecosystems is an important and challenging scientific task. My work is motivated by fundamental questions: how changing climate impacts coastal environments, how past abrupt climatic changes affected marine primary productivity, and how to reliably extract quantitative information on paleoenvironments from marine sediments. The long-term objective of my research program is to calibrate microfossils (primarily dinoflagellate cysts) as biological proxies of environmental conditions in coastal waters, and to advance high-resolution (paleo) environmental reconstructions in the late Quaternary. More specifically, my research is based on the identification of organic-walled microscopic organisms: primarily dinoflagellate cysts, as well as pollen, spores, and foraminiferal organic linings in sediments. These microfossils are well preserved in sediments, and their records contain information about environmental conditions at the time of deposition, which will be used to investigate sea-surface conditions, ocean circulation, climate, and marine primary productivity both now and in the geological past.****This research program aims at the detailed analysis of dinoflagellate cyst sedimentary records from a multitude of geographic locations along the Pacific coast of USA and Canada. It utilizes facilities of the established Paleoenvironmental Laboratory at the University of Victoria, and immense wealth of sedimentary samples collected over the last few years by members of my group and collaborators. The main objectives of my research over the next five years are: 1) to investigate how the climate changes of different magnitude affect phytoplankton composition and primary productivity in coastal waters of British Columbia (BC) and along the margins of Vancouver Island and northern California; 2) to make high-resolution quantitative reconstructions of recent and pre-anthropogenic trends in primary productivity and sea-surface conditions; and 3) to map the timing and magnitude of the major and minor climatic events over the last ~50,000 years recorded in marine sediments, with particular emphasis on the Holocene.****The proposed work will offer high-resolution time series of hydrographic and climate variability in the eastern North Pacific based on dinoflagellate cyst records. This will contribute to our understanding of natural and human induced environmental changes, as well as marine ecosystem responses to these changes. In addition, quantitative reconstructions of marine primary productivity in the late Quaternary are very important for calibration of existing and future models of global climatic changes and carbon sequestration.**