Excerpt: Whatever happened to polar bears? They used to be all climate campaigners could talk about, but now they're essentially absent from headlines. Over the past 20 years, climate activists have elevated various stories of climate catastrophe, then quietly dropped them without apology when the opposing evidence becomes overwhelming. The only constant is the scare tactics.

Protesters used to dress up as polar bears. Al Gore's 2006 film, "An Inconvenient Truth," depicted a sad cartoon polar bear floating away to its death. The Washington Post warned in 2004 that the species could face extinction, and the World Wildlife Fund's chief scientist claimed some polar bear populations would be unable to reproduce by 2012.

Then in the 2010s, campaigners stopped talking about them. After years of misrepresentation, it finally became impossible to ignore the mountain of evidence showing that the global polar-bear population has increased substantially. Whatever negative effect climate change had was swamped by the reduction in hunting of polar bears. The population has risen from around 12,000 in the 1960s to about 26,000.

The same thing has happened with activists' outcry about Australia's Great Barrier Reef. For years, they shouted that the reef was being killed off by rising sea temperatures. After a hurricane extensively damaged the reef in 2009, official Australian estimates of the percent of reef covered in coral reached a record low in 2012. The media overflowed with stories about the great reef catastrophe, and scientists predicted the coral cover would be reduced by another half by 2022. The Guardian even published an obituary in 2014.

The latest official statistics show a completely different picture. For the past three years the Great Barrier Reef has had more coral cover than at any point since records began in 1986, with 2024 setting a new record. This good news gets a fraction of the coverage that the panicked predictions did.

More recently, green campaigners were warning that small Pacific islands would drown as sea levels rose. In 2019 United Nations Secretary-General António Guterres flew all the way to Tuvalu, in the South Pacific, for a Time magazine cover shot. Wearing a suit, he stood up to his thighs in the water behind the headline "Our Sinking Planet." The accompanying article warned the island—and others like it—would be struck "off the map entirely" by rising sea levels.