"The researchers found that
the uncorrected temperature data correlated strongly with data on movements of Earth's core and Earth's length of day until about 1930. They then began to diverge substantially: that is, global surface air temperatures continued to increase, but without corresponding changes in Earth's length of day or movements of Earth's core. This divergence corresponds with a well-documented, robust global warming trend that has been widely attributed to increased levels of human-produced greenhouse gases."
Other links:
https://solarsystem.nasa.gov/news/680/nasa-study-goes-to-ear...
https://www.jpl.nasa.gov/news/nasa-study-goes-to-earths-core...
https://www.co2levels.org/