4°C warming could reduce global economy by 40%

A new study indicates that a 4-degree Celsius rise in global temperatures could cut world economic output by 40% by the end of the century. This is a significantly higher estimate than previous models suggested. The updated model considers how global economies are connected through trade and supply chains. It reveals that climate damage in one area can trigger chain reactions worldwide, impacting all nations. Prior models focused on local weather impacts, potentially leading policymakers to underestimate the economic risks. The new study suggests that damages accelerate beyond a 1.7C rise, supporting deeper emissions cuts.