Eco-anxiety is not an official medical diagnosis, but everyone knows what it means. The American Psychological Association defines it as “the chronic fear of environmental cataclysm that comes from observing the seemingly irrevocable impact of climate change and the associated concern for one’s future and that of next generations”. Fear of the future, an ache for the past, the present awash with disquiet: into this turmoil Alice Mah’s new book appears like a little red boat, keeping hope afloat against all odds. Mah is a professor of urban and environmental studies…