Evolution of orogenic belts, climate change

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Actually, these topics are related. Both the location of the continents and the formation of mountains can affect the climate.

Firstly, continents move across the globe through the process of continental drift. Seafloor spreading is the driving force behind plate tectonics, and is how new crust is generated. Divergent plate boundaries are the oceanic ridges where this occurs. This process is slow in terms of human lifetimes, but geologically speaking enough time has passed for the continents to form three super continents, and break apart, in the last 750 million years. The most recent supercontinent, Pangaea, broke apart 205 million years ago when the Atlantic ocean first began to form.

The positions of the continents determines ocean circulation, which is critical to global climate. Scientifically speaking, there is a thermohaline circulation in the water (thermo meaning heat and saline meaning salt). To be less scientific, warm water is less dense, and salt water is more dense than fresh water. Cold water sinks in the North Atlantic and near Antarctica. As it sinks, it draws in the warmer water behind it. This causes a substantially warmer climate on the eastern, relative to the western side of the Atlantic. The thermohaline circulation was initiated by the closing of the Isthmus of Panama 4 million years ago. As the Atlantic surface currents pass through the Trade Wind Belt they become saltier by evaporation. Instead of moving westward into the Pacific Ocean, as it did before, the salty water is now blocked by Panama and flows into the North Atlantic. There it is chilled and becomes quite dense, forming the sinking North Atlantic Deep Water that begins the deep-current conveyor belt. If the surface water were fresher, it would be less dense.

Tectonic plates are the main reason why volcanoes erupt. Most volcanoes occur near the edges of plates; when the plates collide, one plate slides beneath the other. When the moving plates get deep enough in the mantle, some of the rock on the overlying plate ...