Hello Emilio,
I have another viewpoint that i comes at the Climate Change question from another angle. First we need to understand that ALL IPCC climate models are based on the modelling data found in the CMIP (coupled Model Intercomparison Project) which i believe is currently at CMIP 5, however this coming year there is an UPDATE CMIP 6. As with all updates they look to refine what has already gone before. However in CMIP 1-5 a large portion of Solar (space) weather was left out of the models.
By this i mean we all get heat from the sun, but we get alot more. The sun drives our weather patterns, the solar eruptions shower us with particles and energy waves that react with out own electro static climate and effect us in ways we are only starting to understand.
We also need to remember that our current magnetic poles are moving, quite considerably, in fact they point towards a magnetic reverse, so the poles swap sides. this in turn reduces the magnetic field the protects the earth, allowing even more solar forcing to impact our weather.
Essentially what i am saying is that Climate Change (human made) that we have been sold, with Human CO2 being the main - in certain media circles the ONLY - contributing factors in Climate change. Is not actually factual.
It also points to the fact that we are about to enter a cooling period within the earths climate cycles and not a warming which we are all told about.
So we need to look at the whole picture to understand all sides of this story and of course you have already heard the media view point, but you should listen to a guy called Ben Davidson. 
Kind Regards
Tobiwaan
RE: By the next century, summers could last half a year