The humble bucket turns out to be at the bottom of a perplexing anomaly in the climate records for the twentieth century.

Land and ocean temperature measurements show a strange cooling of about 0.3 °C in the global mean temperature in 1945. A US–British team of climate scientists has now found a surprisingly simple explanation for the long-standing conundrum. It turns out that the mysterious drop is due to differences in the way that British and US ships’ crews measured the sea surface temperature (SST) in the 1940s.