Berry Creative, a Helsinki-based team of designers, has created a series of postage stamps to draw one of the biggest issues facing the world...
This set of three stamps, produced in September 2018 for Finland's postal service "Posti," change when heat is applied to reveal the adverse effects of climate change.
This green one shows an increase in migration. The New York Times Magazine notes that while one percent of the world is an unlivable hot zone today, that could soar to 19 percent by 2070.
It's not the only stamp to draw attention to ecological change. Pablo Doringo's "From Venice With Algae" in March 2020 used polluting algae from the city's rivers to make stamps.