Historical lags between climate change and ice-melt suggest sea level rise may continue for millennia

Climate researchers have found evidence for significant lags between major shifts in global temperature and changes to the size of Greenland’s ice sheet throughout ancient history. These delays suggest that current trends in global warming may cause sea levels to rise for thousands of years, even if we manage to stop or reverse human-induced climate change immediately. Researchers modelled changes to the size of Greenland ice sheet between the last interglacial period (125 millennia ago) to the year 2100. Their simulation shows that the Greenland ice sheet continued to gain mass for several thousand years after it reached its coldest conditions (26 millennia ago), and it continued to lose mass for several thousand years after its warmest period (8 millennia ago). More recently, after a cool period between the mid-Holocene and the industrial era, the ice sheet gained mass for more than a century following the beginning of human-induced global warming in 1850. The authors say this slow response needs to be represented in ice sheet simulations in order to predict ice mass loss, and therefore sea level rise, accurately.