Grant: Discovery Grants Program - Individual

The long-term surface temperature and the heat flowing from the interior of our planet determine the temperature distribution in the upper kilometer of the Earth. If climate does not change, the temperature underground increases linearly with depth. If the Earth's surface warms (cools) heat is gained (lost) by the ground. These changes in the energy balance at the surface propagate and are thus recorded in the subsurface as perturbations to the equilibrium thermal regime. For typical thermal properties, perturbations penetrate approximately 20m in a year, 150m in 100 years and approximately 500m over the course of a millennium. As a result, recent energy balance changes at the surface remain recorded in the shallow subsurface. Analysis of these underground anomalies are the subject of investigations by borehole climatologists to obtain reconstructions of the Earth's past climates over continental areas. These records are the only direct measurements of long-term past temperatures presently available. Thus, it is important to use underground temperatures as a validation tool for large climate models simulating the climate of the past. Such validation will provide confidence when interpreting future climate projections from these models and guide climate change mitigation efforts. In this project, we seek to develop the tools and techniques to integrate large general circulation models with borehole temperature data across the world in an attempt to validate, as well as facilitate the tuning of parameters in the subprograms simulating the physics of climate, thus improving model performance. This proposal calls for significant support for graduate students and a Postdoctoral Fellow, in this way contributing to the retention of the brightest minds in Canada.