“Astronauts in orbit can’t see any human structures. “
False, with the naked eye the average human from the ISS or formerly the shuttle can see the Great Wall of China. Three Gorges Dam is also visible. The multiple man-made Palm Islands in the Persian Gulf as well. With simple binoculars you can see the Pyramids, the Golden Gate Bridge, Hoover dam. The Florida key’s causeway is also visible with naked eyes better with binoculars.
The Chinese was looks like a faint track made my an ant in sand.
If you don’t understand how much bigger Sun is than earth, I am afraid you are very low IQ. That is the whole point. Climate change is from cycles of activities from the mighty sun. Not puny human beings.