Nearly two-thirds of Earth's life-supporting ecosystems, including clean water, pure air, and stable climate, are being degraded by unsustainable use.   
Humans have caused much of this damage during the past half century.

  At our PRESENT rate of degradation of the earths ecosystems ( ECOSYSTEMS THAT ARE NECESSARY FOR OUR VERY  SURVIVAL )
   If we continue with the same 20th century practices and GDP growth the global economy, and the pollution that presently comes with it, the flow of destruction will double in 20-25 years. (rule of 72 )

     People , such as deniers and Mr. Mason that look only at "the economy" are blind to the fact that "the economy" will soon cease to exist as we are killing the earth.

It's like an athlete being told that the steroids he's taking  are on the point of killing his vital organs and therefore  him. To which he replies "I must continue taking them or my performance/ career will suffer".