Climate change is existential absent mitigation

If we contemplate the most extreme possible outcome for Earth's climate future, and given the seeming indifference of political and global corporate elites to heed scientific advice or public sentiment toward decarbonizing the economy, then we are potentially looking at an increase of global temperatures by 5.4 °F (3 °C) by 2050. Scientists predict that at this threshold, the world's ice sheets would disappear, severe droughts would decimate vast sections of the Amazon forest (eradicating one of the world's largest carbon offsets), and Earth would enter a feedback loop of increasingly intense and deadly conditions (Carleton et al., 2021; Hansen et al., 2011; Hsiang et al., 2019; Mulholland, 2019). In this bleak scenario, 35% of the global land area and 55% of the global population would be exposed to lethal heat conditions for more than 20 days a year, pushing the limits of human survivability. Concurrently, droughts, floods, and wildfires would regularly devastate the landscape. About one-third of the world's land surface would transform into deserts. Complete ecosystems, starting with the planet's coral reefs, rainforests, Arctic ice sheets, and the total deglaciation of the Hindu Kush Himalayan region, would collapse. The agricultural productivity of the tropics would be devastated, displacing more than one billion people. This mass migration, coupled with diminishing coastlines and acute shortages of food and water, would strain the societal fabric of the world's most populous nations. Conflicts over resources could escalate, potentially even culminating in nuclear war. If not urgently addressed with comprehensive mitigation strategies and restoration efforts, this scenario could mark the end of global human civilization as we currently know it. It is like sailing in a leaky boat on a stormy sea.