Climate change as a science was in it's infancy 50 years ago. Any predictions being off 50 years later should be understandable by any with even a modicum of scientific knowledge.
And when it comes to future predictions, especially ones decades out, if they aren't 100% correct as we get closer, again this should be understandable. Climate isn't weather. Climate is much more difficult just due to all the variables involved. That said, meteorologists can't even get tomorrow's weather 100% correct 100% of the time. And let's not even get into how difficult it is to predict how strong hurricanes will be or where they will be 5 days out. So expecting climatologists to get the entire world climate 100% right 20 to 50 to 100 years out, is pretty strange.
Climate change science is new. There is still much not known. Future predictions should be fluid. That said, they know enough to be able to determine major trends and directions and the alarm from that community is well founded. They should be heeded.
But if a decade from know things aren't as good or as bad as current projections say, remember, it's still a new science. Man has been studying geology for over a thousand years and still can't prediction earthquakes or volcano eruptions. Physics has been study for a thousand years and we are still clueless about so much in that field.
The media and politicians that deny or sensationalize climate change are doing a massive disservice to the science and the messages coming from the good people that make up 98-99% of the field.