By now we've all heard that the climate is warming, but how do climate scientists study the problem? and how do they know that the current warming trend is unlike anything the earth has ever seen before? What tools do they use, and what can they tell us about how the planet is changing as a result of the build up of carbon dioxide in the atmosphere?
To answer these questions and to go inside the science of climate change, we spend the hour with renowned professor Michael Mann, one of the foremost climate scientists in the world today, and author of the famous 'Hockey Stick' graph.
From climate models, and the detective work behind reconstructing what temperatures were in the past, to the uncertainties of the future, and the personal price that comes with being a climate scientist in such a polarized political environment, our wide-ranging conversation with Michael Mann.
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