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Ontario Tech acknowledges the lands and people of the Mississaugas of Scugog Island First Nation.

We are thankful to be welcome on these lands in friendship. The lands we are situated on are covered by the Williams Treaties and are the traditional territory of the Mississaugas, a branch of the greater Anishinaabeg Nation, including Algonquin, Ojibway, Odawa and Pottawatomi. These lands remain home to many Indigenous nations and peoples.

We acknowledge this land out of respect for the Indigenous nations who have cared for Turtle Island, also called North America, from before the arrival of settler peoples until this day. Most importantly, we acknowledge that the history of these lands has been tainted by poor treatment and a lack of friendship with the First Nations who call them home.

This history is something we are all affected by because we are all treaty people in Canada. We all have a shared history to reflect on, and each of us is affected by this history in different ways. Our past defines our present, but if we move forward as friends and allies, then it does not have to define our future.

Learn more about Indigenous Education and Cultural Services

October 22, 2010

Speaker: Dr. Bill Langford, Department of Mathematics and Statistics, University of Guelph

Title: Poleward Expansion of Hadley Cells

Abstract: A mathematical model has been constructed for the study of convection in a rotating spherical shell of fluid, with radial gravity and a pole-to-equator temperature gradient on the inner boundary. The model fluid satisfies the Navier-Stokes Boussinesq equations. Depending on the strength of the temperature gradient, convection cells appear that are analogous to the Hadley, Ferrel and polar cells of the present day Earth's atmosphere. The model reproduces the trade winds, westerlies, jet streams and polar easterlies of today's Earth's climate. As the temperature gradient is decreased, the Hadley cells slow in their circulation velocity and expand poleward, as recently observed for Earth's climate. Eventually, for still smaller values of the temperature gradient, the Ferrel and polar cells disappear and the resulting circulation resembles that of the "greenhouse" palaeoclimate that dominated the Earth for much of geological time. This is joint work with Greg Lewis of Ontario Tech University.