Our understanding of how and why our own planet "Earth" works is vital to assessing potential risk to life in all its many forms (some people believe that Earth itself is alive "Gaia Hypothesis")
Earth science (also known as geoscience) includes research of the atmosphere, oceans and biosphere, and the solid earth by using physics, chemistry, biology, chronology and mathematics to build a quantitative understanding of how the Earth systems.
Our increasing understanding of water on planet earth is vital.
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