CO2 Levels Already 10% Too High – Hansen Team Study

See the full study, ­­­Target Atmospheric CO₂: Where Should Humanity Aim?

http://www.columbia.edu/~jeh1/2008/TargetCO2_20080317.pdf 

See the one-page summary of this study:   

https://www.ncwarn.org/Programs/NewCoalPlants/TargetAtmosphericCO2Summary.pdf