Intrepid Science Blog

Anthropocene began in 1965, according to signs left in the world's 'loneliest tree' Pavla Fenwick , Author provided Chris Turney , UNSW ; Jonathan Palmer , UNSW , and Mark Maslin , UCL On Campbell Island in the Southern Ocean, some 400 miles south of New Zealand, is a single Sitka spruce. More than 170 miles from any other tree, it is often credited as the “world’s loneliest tree”. Planted in the early 20th century by Lord Ranfurly, governor of New Zealand, the tree’s wood has recorded the radiocarbon produced by above ground atomic bomb tests – and its annual layers show a peak in 1965, just after the tests were banned. The tree therefore gives us a potential marker for the start of the Anthropocene. But why 1965? The 1960s is a decade forever associated with the hippie movement and the birth of the modern environmentalism, a sun-blushed age in which the Apollo moon landings gave us the iconic image of a fragile planet fra...

There’s an old sailor’s expression: “Below 40 degrees south there is no law, below 50 degrees south there is no God.” Since the sixteenth century, sailors have spoken in awe of the violent westerly winds and seas they experienced fighting their way across the Southern Ocean. With few landmasses to slow them down, the winds found across 40 degrees latitude often reach speeds of twenty-five knots—about 40 percent stronger than their northern hemisphere counterparts—earning them the title the “roaring forties.” As shipping pushed farther south, explorers realized that these winds form part of a vast storm belt that includes the “furious fifties” and “screaming sixties,” names more reminiscent of terrible rock bands than a major part of our planet’s circulation system. The early hunters and traders didn’t understand it at the time, but these winds are created by a procession of low-pressure systems carried east by the jet stream, a river of cold air hurtling and twisting round the Antarct...