Getting back to 350 ppm will be difficult and will take time. By the time we get back to 350 ppm, we will know a lot more and we will be able to be more specific about what “less than 350 ppm” means. By then we should be measuring Earth’s energy balance very accurately. We will know whether the planet is back in energy balance and we will be able to see whether climate is stabilizing.
The worst hurricane, tornado, flood, drought, and heatwave all occurred with CO2 well below 350 ppm.










