High-resolution Holocene climate derived from lacustrine sediment: stable isotope evidence from organic and inorganic proxy material

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UN Secretary General Ban Ki-moon declared climate change as "the defining challenge of our era.Grave as it may be, today's financial crisis is a passing storm from which we will recover, we cannot say that about the potential catastrophe of global warming." This interdisciplinary DG seeks to characterize modern meteorological/isotopic parameters (d18OH2O and dDH2O) of surface waters from western Canada and characterize Holocene climate from lake sediment and molluscan isotope proxy data (d18OCaCO3/d13CCaCO3/d13Corg/d15Norg/ dDcell/d18Ocell). Changes in seasonality of temperature and precipitation recorded by stable isotope proxy data during abrupt climate change intervals that punctuate long-term trends will be derived by micromilling mollusc shells for carbonate d18O and d13C values. There is currently no issue of greater scientific significance and urgency than gaining an understanding of the Earth's climate system in the modern and through time. It is critical to all aspects of human society, as well as for global and regional ecosystems, that we increase our understanding of both past and contemporary climatic regimes in order that we may better predict, and prepare for future changes in climate. ***At particular risk are the high latitudes where decreasing sea ice directly affects biota, thermohaline circulation, heat transport, and the radiation balance, as well as human systems. Melting permafrost will generate methane and CO2 that will further warm the atmosphere. Ice roads that supply northern communities and oil/mining infrastructure will operate less frequently, thereby increasing costs as well as risk of accidents and spills in delicate pristine environments. Northern communities face new and ever more daunting challenges as their way of life is further threatened. Migrations will be altered and whole ecosystems may move north and/or disappear. Particularly sensitive to climate change are regions that have agriculture and/or fishing-based economies, large heating energy requirements, and/or marginal water supplies.***Because Canada is not isolated from other Northern Hemispheric landmasses and oceans, all must be evaluated together if we are to understand past, present, and future changes in Canada. Our recent research has revealed that moisture transport over Central America is directly related to moisture and heat transport to the North Atlantic, and that the Canadian Arctic is more sensitive to climate change than previously thought. The proposed Discovery Grant research will recreate temperature, moisture cycling, and atmospheric circulation at a variety of time-scales (decadal to subannual) to evaluate teleconnections between locations. We will apply time-series analysis to these proxy data to evaluate climate-change periodicity in the past as a function of location to better predict regional responses to anthropogenic forcing in the future.