If "Global Warming" exists due to anthropogenic activity there are no relationships between it and earthquakes. But what about Global Cooling? :)

The idea of global cooling reached the public press in the mid-1970s WHEN scientists were becoming increasingly aware that estimates of globaL temperatures showed cooling since 1945 BUT temperatures had stopped falling as well as the possibility of large scale warming due to emissions of greenhouse gases In the scientific papers which considered climate trends of the 21st century .

Wikipedia says "The temperature of the crust increases with depth,[11] reaching values typically in the range from about 200 °C (392 °F) to 400 °C (752 °F) at the boundary with the underlying mantle. The temperature increases by as much as 30 °C (54 °F) for every kilometer locally in the upper part of the crust, but the geothermal gradient is smaller in deeper crust.[12] " https://en.wikipedia.org/wiki/Crust_(geology)

Global warming has increased the surface temperature by about 1 °C since the Industrial Revolution, and so if the temperature gradient remains unchanged regions of the lithosphere will now be 1 °C warmer. If this leads to these regions changing from solid to liquid then that transition may result is volcanism.