Modern and Deep Time oceanography (SSC, SLC) & climatology (SST): insight from brachiopod archives

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Climate change and the postulated associated biotic crisis are gripping the 21st century, and we are in desperate need for critical information from extremely sensitive environments - warm and cold - to better document the impacts of global warming on our society. Canada's large northern polar region may undergo some dramatic and drastic changes in a relatively short time period. ***As part of my program, I plan to study compositional changes and environmental relationships in modern and ancient brachiopods (lampshells) - from extreme environments such as tropical, polar and deep regions of the global ocean. This baseline information will be critical in determining the rate of climate change for highly sensitive environments and to assess the impact of the rate of change. Insight for impacts, effects and outcomes will be sought from ancient brachiopods present during climatic events of the geologic past such as the Late Paleozoic Ice Age, which dwarfs the last ice age, from the end Permian mass extinction event, with its catastrophic warming that caused the - almost life-ending - biotic crisis in geologic history, and the end Triassic mass extinction, which drastically changed life on our planet with the rise of the dinosaurs. ***Lampshells secrete shells consisting of calcite that is relatively stable to the vagaries of time but changes its composition with changes in the composition of the ambient seawater. Equilibrium incorporation of trace elements and stable isotopes into shell calcite and coupled with isotope thermometry are fundamental underpinnings of brachiopod-based paleoclimatology and paleoceanography (Brand et al., 2013, 2014). Thus, if the chemistry of seawater changes due to acidification brought about by the incorporation of anthropogenic carbon dioxide, we can document these changes by analyzing the trace and isotope chemistry of brachiopod shells. This principle applies to many other climate-change related factors, such as the melting of the ice caps and sea ice and warming of the oceans, and this information will be stored by brachiopods in their shell calcite.***Brachiopods are excellent recorders (archives) of climatic events affecting the oceans and the Earth. Detailed geochemical analyses supplemented with nanostructural analysis of brachiopod shells from specific and focused events/horizons will provide us with critical information of these events in the geologic past, and of changes in the past 100 years since the start of the industrial revolution. This work will be immensely important to the fields of paleoclimatology and paleoceanography, and may influence policy decisions regarding our sensitive and fragile polar region and its resource and tourism developments, shelf areas in the Canadian Arctic, and sovereignty over the Canadian Arctic Ocean.*** **