It's not the sun

Climate denialists' favourite "explanation" for global warming (when they're not claiming that the temperature data are made up) is that the sun has got warmer.

Here's a nice piece from Carbon Brief by Zeke Hausfather (who worked with Robert Muller at Berkeley Earth)   This is the chart from that piece comparing solar irradiance and global temperatures.  As Hausfather points out, solar irradiance has declined since the 1970s, while global temperatures have risen.  Just looking at the chart, I would say there is some sort of cyclical relationship with the 11-year sunspot cycle roughly corresponding with a similar (but more random) temperature cycle, which fluctuates around a rising trend.  It's the trend that matters.  And the irradiance trend is gently down, which the temperature trend is strongly up.

Source

See also: Is it the sun?