World Beneath Ice. John Russell Fearn

The sun is dying. Astronomers can see that the Earth will soon become a frozen planet. All life will vanish from the surface, and the sea and air will freeze, as the light of the sun dwindles to that of a full moon. Mankind is forced to retreat underground, there to try surviving in vast underground habitats–trapped in a World Beneath Ice. Only one person on Earth has the scientific knowledge to rekindle the sun–the incredible Golden Amazon, a woman changed by surgery and genetic engineering into a superwoman. But she's been missing for eighteen months, lost in space.... Is this the end of humankind? Book One in The Golden Amazon Saga, a fantastic new SF adventure series wrenched from the pages of the pulps.