There was global cooling 40 years ago.
Actually, that was left over from the optical pollution levels from before the ecological clean up in the west in the early 70s. Boomers seem to forget what the skies looked liked before then, and that was in an era all ready cleaned up from the 20s. There is coal dust in the Arctic and Antarctic ice record in the 1870s to 1940s period. Most of the old Cathedrals in Europe are now grey, cleaned up from black, many many shades darker than when they were built still.
The air quality since the 70s in most of the developed nations has clarified by several scales of magnitude, and this lets the ground heat. Also in that same period, the world's population has doubled, and energy consumption globally has nearly tripled.
Now consider that for each exajoule consumed, due to our 30% efficiency in production as well as 70% energy released as heat released in consumption, we release 4 exajoules of heat into the environment, so the growth of energy in the environment has exponential growth on top of the exponent of consumption growth in the graph. Heck, think of how much heat just the internet creates, that is an addition that never existed 30 years ago, but is significant especially when you consider how much extra heat is created through airconditioning in order to move that heat away from the servers and user stations.
While the atmosphere may be clearer now and allow through more solar energy, the amount of clean CO2 we pump into the atmosphere has increased exponentially with the energy production curve. CO2 is like a two way mirror, it allows energy through one way much more efficiently than the other.
Now to top this off, we are coming into a cycle of a lot of geological activity. Lots of volcanos popping off, lots of earthquakes happening. This all releases more energy and CO2 into the atmosphere.
The thing is, the planet can only handle so much, and natural forces and sources alone are able to overwhelm it and make it uninhabitable. We have added so much energy and insulation to the system, that the level of natural event required to make the planet uninhabitable has been greatly reduced, and in fact, we are putting enough in that we have had an effect even during a geological lull in activity. If any of the super volcanos blows, our continued existence is in serious jeopardy.
We have always been meant to evolve off this planet, but we can't because we can't cooperate and would rather waste all our resources on making money by turning resources into garbage.
