Rodinia and the SnowBall Earth Hypothesis

How Continental Positioning affects Climate: Part II – Possible Snowball Earth Triggering Mechanisms + Regional Effects of Mountain Ranges

In Part 1 of this article, I outlined some of the variables which can affect Earth’s climate, and gave a brief overview of plate tectonics, and how changes in continental positioning can lead to climate change through albedo feedback and via the alteration of ocean circulation and heat distribution patterns. In doing so, I used the example of the Rodinia Supercontinent and the Snowball Earth hypothesis of the Neoproterozoic era in order to relate the concepts to events in Earth’s prehistory. For the sake of completeness, I want to finish up that example by briefly going over a few proposed triggering mechanisms that could have made a runaway albedo feedback loop possible in the Cryogenian period. After that, I want to go over the ways in which the presence of mountain ranges can affect local and regional climate. (more…)

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By Credible Hulk, ago

How Continental Positioning affects Climate: Part I – Plate Tectonics, Albedo, and the SnowBall Earth Hypothesis

About 700 – 800 MYA, during the Neoproterozoic era (in the late Precambrian), it has been proposed that the Supercontinent, Rodinia occupied an equatorial position on the Earth. Perhaps counter-intuitively, this tropical arrangement of the continents may have set the stage for a massive glaciation known as “Snowball Earth” during the Cryogenian period, despite equatorial regions receiving the most sunlight due to the orientation of the Earth with respect to the sun. Indeed, the fact that equatorial regions receive the most sunlight is part of the reason why tropical rainforest biomes exist where they do. So how could this have happened? Why would an equatorial continental arrangement render such a glaciation more likely? More on the Snowball Earth hypothesis in a moment: More generally however, what factors are capable of inducing changes in the climate?

There are several of them. First of all though, what do we mean by climate, and how does it differ from weather?  (more…)

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By Credible Hulk, ago