Study of tree rings dating back to Roman empire concludes weather since 2014 has been extraordinary
The series of severe droughts and heatwaves in Europe since 2014 is the most extreme for more than 2,000 years, research suggests.
The study analysed tree rings dating as far back as the Roman empire to create the longest such record to date. The scientists said global heating was the most probable cause of the recent rise in extreme heat.
