Scientists have looked back in time to reconstruct the past life of Antarctica’s “Doomsday Glacier” — nicknamed because its collapse could cause catastrophic sea level rise. They have discovered it started retreating rapidly in the 1940s, according to a new study that provides an alarming insight into future melting. The Thwaites Glacier in West Antarctica is the world’s widest and roughly the size of Florida. Scientists knew it had been losing ice at an accelerating rate since the 1970s, but because satellite data only goes back a few decades, they didn’t know exactly when significant melting began. Now there is...