We do not have 2 decades. According to the Job One for Humanity website, the deadline to address this is no later than December 31, 2024, which is when the average CO2 emissions will past the 425 ppm threshold. After this threshold is passed, we expect a major increase in severe weather events and other disasters that will ultimately lead to a major population decline which will begin in the 2030s but will not become noticeable until 2050.