Australian-led researchers say global temperatures may have already risen by 1.5 degrees

Global temperatures may have already risen by 1.5 degrees since the pre-industrial period, according to an Australian-led team of researchers. They warn that warming could reach 2 degrees by the end of the decade - much sooner than predicted. Their findings come from an unusual source - rare, sea sponges that have a lifespan of hundreds of years.

Scuba diver extracting sponge from underwater Credit: Clark Sherman Amos Winter