Jeremy Corbyn’s astrophysicist brother has claimed that ‘man-made climate change does not exist’ and is ‘manufactured’ by journalists. Piers Corbyn, 72, says claims of widespread consensus on the topic of man-made climate change are false. In April, Piers branded 16-year-old environmental activist Greta Thunberg an ‘ignorant brainwashed child’ who ‘suffers mental abuse by manipulative adults’. Piers believes the root cause of rising temperatures is solar activity which produces natural climate change cycles.