!- first boundary : 1.5 deg C is a physical boundary - we cannot it it we want to retain a planet safe for human civilization - “ If the world breaches 1.5C, we are likely to trigger at least five tipping points, including the irreversible melting of the Greenland ice sheet and loss of the world’s tropical coral reef systems. This will be devastating for future generations. It will literally change the world, and yet every month we use 1% of the remaining carbon budget for 1.5ºC.” From earth commission website: https://earthcommission.org/news/earth-commission-news/pioneering-science-reveals-set-of-earth-system-boundaries-that-can-secure-a-safe-and-just-planet-for-all/