Summer climate hoax book for teens envisions a world where trace amounts of CO2 have caused most of the world to be underwater

Summer [climate hoax book] for teens - Herald Scotland

Aurora by Julie Bertagna (Macmillan, £6.99)
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Post climate change, most of the world is underwater. Having rescued her people from the drowned city of Glasgow, Mara and her refugees have made a new life in what remains of Greenland, but this peaceful pastoral existence is threatened by the imperial ambitions of other survivors, who live in sky cities...
...This is both a powerful fable with a ring of truth and a closely observed portrait of a girl coming of age...