In May 1953, news about the danger of the accumulation of carbon dioxide in the atmosphere circulated around the world for the first time. We got used to many things. To images of wildfires and incinerated animals, to ice sheets calving into the ocean, to promises by world leaders to heed scientists' "last chance" warning. It's hard for anyone under 40 to remember a time when carbon dioxide build-up, whether it was the "greenhouse effect" or "global warming" or "climate change" — or now the "climate crisis" — wasn't in the news. The Long Hot Summer of 1988 - 35 years ago! – is considered to be the moment when world leaders began to show proper piety. Presidential candidate (and soon to be president) George HW Bush said he would use the "White House effect" to fix the greenhouse effect (he didn't). British Prime Minister Margaret Thatcher warned of a huge experiment being carried out "with the very system of this planet". Thirty-five years. But it was actually 35 years ago - 70 years ago this month - that the dangers of the build-up of carbon dioxide in the atmosphere first made the rounds. That carbon dioxide, trapped heat, was uncontroversial. The Irish scientist John Tyndall (probably drawing on the work of the American Eunice Foote) showed that this was already the case in the middle of the 19th century. In 1895, Swedish Nobel laureate Svante Arrhenius proposed that over hundreds of years, the build-up of carbon dioxide released by burning oil, coal and gas could trap enough heat to melt the tundra and make freezing winters a thing of the past. (Marc Hudson, FastCompany)