Let's see what would be needed to make Earth as uninhabitable as Mars? This disaster would need to 

• Remove 99% of the Earth's atmosphere, and all of its oxygen.
• Remove all the water in the oceans, leaving just the Antarctic ice cap - and even then that's too much ice. ExoMars with its ground penetrating radar discovered that both polar ice caps have layers of ice up to 3.5 kms deep, and that there are thick layers of ice extending over a much larger area than the visible ice caps, mixed with soil (enough frozen water to cover entire surface of Mars with liquid to a depth of 11 meters).
  Antarctica has enough ice so that if it melted it would raise the oceans by 60 meters. See Quick facts on ice sheets.
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• Remove the Earth's magnetic field, our protection from solar storms
• Remove all life from the surface of Earth of course, and