Past: A History of Earth

The Earth was once virtually deep frozen, buried in massive ice sheets with surface temperatures of -50°C. It’s widely thought that this “Snowball Earth”, 700 million years ago, was triggered by the breakup of a supercontinent called Rodinia. This caused increased weathering and consumed atmospheric CO2, propelling the Earth into a severe ice age. Surprisingly, the consequences of widespread underwater volcanism have been overlooked. We will explore how this process explains many strange phenomena during and after Snowball Earth, and how it may have stimulated the origin of complex life.

US presidential candidate Ted Cruz in a recent hearing of the US Senate on climate change said that our understanding of it from computer models is “profoundly wrong…and inconsistent with the evidence and the data”. This is just one example of the anti-climate change rhetoric that one can hear these days. Much of it cherry picks temperature data and exploits uncertainty in model simulations. In this talk I will go over the fundamentals of the science behind climate change and illustrate how we know that higher concentrations of CO2 in the atmosphere = warmer temperatures.