Based On The Organic Proxies To Reconstruct The Climate Evolution In The Continental Margin Shelf Sea Of East Canada During The Holocene

Modern climate science theory holds that the north Atlantic ocean is a sensitive area of global climate change,and the development of climate change in this area will have a profound impact on global climate through global thermohaline circulation.Since the Quaternary,especially since the Last Ice Age,the Laurentide Ice Sheet has had a significant impact on the climate change in the North Atlantic ocean.Hu2006040-40pc is located on the continental shelf of eastern Labrador,Canada.58°75.839'N,61°86.866'W,203 meters water depth,climate records dating back to the Holocene 10,000 years ago.In view of the historical research,TEX₈₆has never been used for temperature reconstruction in this area.Therefore this research takes the lead in TEX₈₆through this stance and BIT organic biomarkers proxies analysis,using the calculation formula of sea surface temperature?SST?and terrigenous input proportion,compared with the modern sea surface temperature data,verify TEX₈₆feasibility in temperature reconstruction in the waters,fill TEX₈₆reconstruction of sea surface temperature of blank in this sea area.Combined with benthic foraminiferal assemblages,Ca/Ti and TOC,the climatic evolution process since Holocene in shelf waters at the eastern Canadian continental margin.The sea surface temperature derived from TEX₈₆is basically consistent with the trend of temperature change since the Holocene in the northern hemisphere.The Holocene climate change experience in this area can be subdivided into early,middle and late Holocene,presenting a cold-warm-cold change process.10ka.BP-8ka.BP:in the early Holocene characterized by the slow rise of sea surface temperature and the transformation of permanent sea ice into seasonal sea ice,the significant decrease of land-source input was related to the decrease of moraine input caused by glacier melting.8ka.BP-4ka.BP,the sea surface temperature increased significantly in the middle Holocene,which was1-1.5?higher than the modern SST.4ka.BP to modern times,the advent of"new ice age",the decline of solar radiation,frequent volcanic activities and other factors caused the overall decline of sea surface temperature.Throughout the Holocene,a number of short period cold events and warm events occurred in each climatic stage,with the performance of 8.2ka cold events being extra prominent.8.2ka cold event is closely related to the melting of Laurentian Ice Sheet and the release of fresh water.Since the late Holocene,short scale climate abnormal events different degrees of effects on the process of human civilization,though not with 8.2 ka cold events,but continued rapidly in global warming,the polar ice caps melt under the background of similar drive mechanism,continuous warming will produce a"frog effect",paralysis of human consciousness,improve the climate have incalculable consequences.The emphasis on the study of climate anomalies and the discussion of the past and the present will enable mankind to have an overall grasp of the future trend of climate,find the law of climate development,and work together against the fate.