For his follow-up to the 2015 doco hit “That Sugar Film,” Damon Gameau tackles the most open, most challenging topic of all: climate change. “2040” is his unabashedly positive global search for technologies and solutions which he claims are readily available right now. Using a quirky lens of zooming forward to 2040, when his daughter will be 25, he travels the world to find positive messages, expound their virtues, and then cinematically imagine them into life in 2040. The big picture ideas he exhumes include electricity microgrids, driverless electric vehicles, soil regeneration, Raworth’s “doughnut economics,” seaweed permaculture, carbon sequestration, education/empowerment of women (to reduce population growth), and the use of energy dashboards. The movie is artfully constructed and none of the tech stuff drags. Gameau himself is an engaging tour guide and his cast of do-gooders and smart folks is terrific. Viewers can argue about the achievability of any or all of these ideas, but the overall vibe of the film – that plenty of positive possibilities can be harnessed – is infectious. We all know the Doctor Doom scenarios. What we need is motivation, and Gameau’s film is a cool blast of human hope.