Your right, doomsday predictions are common and "scientists" are...

Your right, doomsday predictions are common and "scientists" are political animals as well. There are also mad scientists out there. Science requires theories first, then they have to be proved. Obviously none of these doomsday scenarios(theories) were 'proved'. 

But this is different. Climate change is accepted by 98% of scientists and govts and the world is trying to figure out a way to deal with it.

It has gone a long way past essays in scientific journals. It is mainstream at the highest levels. 

CO2 ppm is not an idea. It is a fact. Shown to be increasing for decades now. They can measure it accurately using ice cores from the poles going back 100s of thousands of years.

CO2  causes the greenhouse effect. Thermodynamics 101. The planet is trapping its own heat.  From the sun and from what we produce ourselves. The heat melts ice caps. The oceans expand when warmer, and this separate to the new water added.  Weather changes dramatically.  Ecosystems change dramatically. There is no argument.   It is a question of finding a solution.   

Things are well past denying the problem. The future of mankind is at stake here.