I vaguely remember a report from, I think it was the 90s? Where it predicted what would happen if CO2 emissions grew exponentially (no reduction in growth), lin

I vaguely remember a report from, I think it was the 90s? Where it predicted what would happen if CO2 emissions grew exponentially (no reduction in growth), linearly (reduction in growth), or stopped (complete cessation of growth). And because of CO2 reduction agreements we got to linear instead of exponential growth. I'll find the exact report and outcome I'm thinking of, but we can be hitting a new record this year and also it's not as bad as it could have been. Edit: it was a report by James Hansen in 1988.