Earth has seen a number of unique geological and climatic changes over its 4.54 billion years of existence in the solar system. One such phenomenon took place more than 700 million years ago, which saw the earth turn into a giant snowball. This state of the green planet is popular among scientists as the "Snowball Earth" phase.
According to BBC, the "Snowball Earth" is a hypothesis that speaks about the freezing of the earth's surface from one pole to another. Supporters of this phenomenon say that sedimentary deposits of glacial origin were formed due to it that covered the entire earth in a blanket of snow. The "Snowball Earth" episodes are claimed to have occurred before the sudden radiation of multicellular bio-forms called the "Cambrian explosion".
The scientists claim that the "Snowball Earth" event occurs once in a billion years. The last one is said to be responsible for the evolution of "multicellularity". Another phenomenon called "Huronian glaciation" that took place 2400 to 2100 million years ago, might have been triggered due to the first appearance of oxygen in the atmosphere known as the "Great Oxygenation Event".
According to Mail Online, scientists were at first of the opinion that a chemical reaction between basaltic rock and carbon dioxide in the atmosphere could have given rise to the formation of ice. But that being a phenomenon that would take longer time, the scientists depended on the shooting of massive amount of aerosols into the atmosphere due to continuous volcanic eruptions, which rapidly cooled earth. The uniqueness about these eruptions is that they might have exerted a considerable amount of sulfur dioxide in the atmosphere, blocking the sun rays and cooling off the temperature by some degrees.
The ice that was formed due to the phenomenon reflected back the sunlight from touching the surface causing to cool off the planet even further. This caused rapid formation of the "Snowball earth". The scientists are also of the opinion that this kind of phenomenon can take place in the future as well.
The research has shown that there should be a clear idea about stable equilibrium conditions and habitable zones on earth. The researchers also say that this study can help in understanding past extinctions and predict how proposed geoengineering tactics can affect the climatic changes in the future.
