A new study has just dropped a bombshell: the collapse of ice sheets at both poles is coming sooner than we thought. Even if we manage to keep Earth's temperatures from rising more than 2 degrees Celsius, Greenland and Antarctica's massive ice sheets are still headed for irreversible melting, warns climate physicist Axel Timmermann from the Institute for Basic Science in Korea. Here's a look.
That's because computer models that simulate the dynamics of these ice sheets often don't account for feedback mechanisms that can affect ocean processes, which then feed back onto the ice sheet and atmosphere. But now, Pusan National University climate scientist Jun Young Park and colleagues have included these missing factors in their modeling - and they predict a major tipping point is approaching faster than expected. What does this mean for us? Well, global sea levels have already risen about 20 centimeters on average over the last century. If we miss our emissions target, the acceleration of melting will put one in 10 people at direct risk from rising sea levels. That means hundreds of millions of people living in small island developing states and other low-lying coastal areas around the world are facing a "torrent of trouble," according to UN secretary-general Antonio Guterres.
"We would witness a mass exodus of entire populations on a biblical scale," he warns. It's not just small island nations that will be affected. Major cities across every continent will feel the impact, including Cairo, Mumbai, Shanghai, London, Los Angeles, New York and Buenos Aires. The potential consequences are staggering.
But there is hope. The only way to avoid this rapid acceleration in sea level rise is by keeping temperatures below 1.5 degrees Celsius - and even then, it's not guaranteed. We need to take action now to reduce greenhouse gas emissions as quickly as possible if we want to minimize the risks associated with losing major ice sheets. "It's crucial that developments like this are brought into our state-of-the-art climate models," says atmospheric scientist Robin Smith. "Even though more work needs to be done to reduce uncertainty in projections like these, this study clearly shows the importance of taking rapid action." Every bit counts when it comes to avoiding catastrophic consequences for future generations...