Tectonic-Scale Climate Change

Faint Young Sun Paradox

Three Possible Solutions

Chemical Weathering

Negative Feedback From Chemical Weathering

Earth’s Thermostat – Chemical Weathering

Climate Changes in the Last 500 Myr

Plate Tectonics and Climate

The Polar Position Hypothesis

Tectonic Control of CO₂ Input – The Seafloor Spreading Rate Hypothesis

Negative Feedback in Seafloor Spreading Hypothesis

Tectonic Control of CO₂ Removal – The Uplift Weathering Hypothesis

Can These Two Hypotheses Explain Tectonic-Scale Climate Changes?

Greenhouse Earth – 100Myr Ago

One Reason: Higher CO₂ Level

Ocean Heat Transport Factor

Why the Cooling over the Last 50 Myr?

Summary: Tectonic Control of Climate